* [PATCH] gcc: Fix CVE-2021-42574
@ 2021-12-14 10:46 Pgowda
2021-12-14 17:31 ` [OE-core] " Randy MacLeod
0 siblings, 1 reply; 4+ messages in thread
From: Pgowda @ 2021-12-14 10:46 UTC (permalink / raw)
To: openembedded-core; +Cc: richard.purdie, rwmacleod, umesh.kalappa0, pgowda
Upstream-Status: Backport [https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=bd5e882cf6e0def3dd1bc106075d59a303fe0d1e]
Upstream-Status: Backport [https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=51c500269bf53749b107807d84271385fad35628]
Upstream-Status: Backport [https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=1a7f2c0774129750fdf73e9f1b78f0ce983c9ab3]
Upstream-Status: Backport [https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=bef32d4a28595e933f24fef378cf052a30b674a7]
Signed-off-by: pgowda <pgowda.cve@gmail.com>
---
meta/recipes-devtools/gcc/gcc-11.2.inc | 4 +
.../gcc/gcc/0001-CVE-2021-42574.patch | 2282 +++++++++++++++++
.../gcc/gcc/0002-CVE-2021-42574.patch | 1765 +++++++++++++
.../gcc/gcc/0003-CVE-2021-42574.patch | 142 +
.../gcc/gcc/0004-CVE-2021-42574.patch | 573 +++++
5 files changed, 4766 insertions(+)
create mode 100644 meta/recipes-devtools/gcc/gcc/0001-CVE-2021-42574.patch
create mode 100644 meta/recipes-devtools/gcc/gcc/0002-CVE-2021-42574.patch
create mode 100644 meta/recipes-devtools/gcc/gcc/0003-CVE-2021-42574.patch
create mode 100644 meta/recipes-devtools/gcc/gcc/0004-CVE-2021-42574.patch
diff --git a/meta/recipes-devtools/gcc/gcc-11.2.inc b/meta/recipes-devtools/gcc/gcc-11.2.inc
index c1293229b6..e352c958de 100644
--- a/meta/recipes-devtools/gcc/gcc-11.2.inc
+++ b/meta/recipes-devtools/gcc/gcc-11.2.inc
@@ -63,6 +63,10 @@ SRC_URI = "\
file://0002-CVE-2021-35465.patch \
file://0003-CVE-2021-35465.patch \
file://0004-CVE-2021-35465.patch \
+ file://0001-CVE-2021-42574.patch \
+ file://0002-CVE-2021-42574.patch \
+ file://0003-CVE-2021-42574.patch \
+ file://0004-CVE-2021-42574.patch \
"
SRC_URI[sha256sum] = "d08edc536b54c372a1010ff6619dd274c0f1603aa49212ba20f7aa2cda36fa8b"
diff --git a/meta/recipes-devtools/gcc/gcc/0001-CVE-2021-42574.patch b/meta/recipes-devtools/gcc/gcc/0001-CVE-2021-42574.patch
new file mode 100644
index 0000000000..4d680ccc8f
--- /dev/null
+++ b/meta/recipes-devtools/gcc/gcc/0001-CVE-2021-42574.patch
@@ -0,0 +1,2282 @@
+From bd5e882cf6e0def3dd1bc106075d59a303fe0d1e Mon Sep 17 00:00:00 2001
+From: David Malcolm <dmalcolm@redhat.com>
+Date: Mon, 18 Oct 2021 18:55:31 -0400
+Subject: [PATCH] diagnostics: escape non-ASCII source bytes for certain
+ diagnostics
+MIME-Version: 1.0
+Content-Type: text/plain; charset=utf8
+Content-Transfer-Encoding: 8bit
+
+This patch adds support to GCC's diagnostic subsystem for escaping certain
+bytes and Unicode characters when quoting source code.
+
+Specifically, this patch adds a new flag rich_location::m_escape_on_output
+which is a hint from a diagnostic that non-ASCII bytes in the pertinent
+lines of the user's source code should be escaped when printed.
+
+The patch sets this for the following diagnostics:
+- when complaining about stray bytes in the program (when these
+are non-printable)
+- when complaining about "null character(s) ignored");
+- for -Wnormalized= (and generate source ranges for such warnings)
+
+The escaping is controlled by a new option:
+ -fdiagnostics-escape-format=[unicode|bytes]
+
+For example, consider a diagnostic involing a source line containing the
+string "before" followed by the Unicode character U+03C0 ("GREEK SMALL
+LETTER PI", with UTF-8 encoding 0xCF 0x80) followed by the byte 0xBF
+(a stray UTF-8 trailing byte), followed by the string "after", where the
+diagnostic highlights the U+03C0 character.
+
+By default, this line will be printed verbatim to the user when
+reporting a diagnostic at it, as:
+
+ beforeÏXafter
+ ^
+
+(using X for the stray byte to avoid putting invalid UTF-8 in this
+commit message)
+
+If the diagnostic sets the "escape" flag, it will be printed as:
+
+ before<U+03C0><BF>after
+ ^~~~~~~~
+
+with -fdiagnostics-escape-format=unicode (the default), or as:
+
+ before<CF><80><BF>after
+ ^~~~~~~~
+
+if the user supplies -fdiagnostics-escape-format=bytes.
+
+This only affects how the source is printed; it does not affect
+how column numbers that are printed (as per -fdiagnostics-column-unit=
+and -fdiagnostics-column-origin=).
+
+gcc/c-family/ChangeLog:
+ * c-lex.c (c_lex_with_flags): When complaining about non-printable
+ CPP_OTHER tokens, set the "escape on output" flag.
+
+gcc/ChangeLog:
+ * common.opt (fdiagnostics-escape-format=): New.
+ (diagnostics_escape_format): New enum.
+ (DIAGNOSTICS_ESCAPE_FORMAT_UNICODE): New enum value.
+ (DIAGNOSTICS_ESCAPE_FORMAT_BYTES): Likewise.
+ * diagnostic-format-json.cc (json_end_diagnostic): Add
+ "escape-source" attribute.
+ * diagnostic-show-locus.c
+ (exploc_with_display_col::exploc_with_display_col): Replace
+ "tabstop" param with a cpp_char_column_policy and add an "aspect"
+ param. Use these to compute m_display_col accordingly.
+ (struct char_display_policy): New struct.
+ (layout::m_policy): New field.
+ (layout::m_escape_on_output): New field.
+ (def_policy): New function.
+ (make_range): Update for changes to exploc_with_display_col ctor.
+ (default_print_decoded_ch): New.
+ (width_per_escaped_byte): New.
+ (escape_as_bytes_width): New.
+ (escape_as_bytes_print): New.
+ (escape_as_unicode_width): New.
+ (escape_as_unicode_print): New.
+ (make_policy): New.
+ (layout::layout): Initialize new fields. Update m_exploc ctor
+ call for above change to ctor.
+ (layout::maybe_add_location_range): Update for changes to
+ exploc_with_display_col ctor.
+ (layout::calculate_x_offset_display): Update for change to
+ cpp_display_width.
+ (layout::print_source_line): Pass policy
+ to cpp_display_width_computation. Capture cpp_decoded_char when
+ calling process_next_codepoint. Move printing of source code to
+ m_policy.m_print_cb.
+ (line_label::line_label): Pass in policy rather than context.
+ (layout::print_any_labels): Update for change to line_label ctor.
+ (get_affected_range): Pass in policy rather than context, updating
+ calls to location_compute_display_column accordingly.
+ (get_printed_columns): Likewise, also for cpp_display_width.
+ (correction::correction): Pass in policy rather than tabstop.
+ (correction::compute_display_cols): Pass m_policy rather than
+ m_tabstop to cpp_display_width.
+ (correction::m_tabstop): Replace with...
+ (correction::m_policy): ...this.
+ (line_corrections::line_corrections): Pass in policy rather than
+ context.
+ (line_corrections::m_context): Replace with...
+ (line_corrections::m_policy): ...this.
+ (line_corrections::add_hint): Update to use m_policy rather than
+ m_context.
+ (line_corrections::add_hint): Likewise.
+ (layout::print_trailing_fixits): Likewise.
+ (selftest::test_display_widths): New.
+ (selftest::test_layout_x_offset_display_utf8): Update to use
+ policy rather than tabstop.
+ (selftest::test_one_liner_labels_utf8): Add test of escaping
+ source lines.
+ (selftest::test_diagnostic_show_locus_one_liner_utf8): Update to
+ use policy rather than tabstop.
+ (selftest::test_overlapped_fixit_printing): Likewise.
+ (selftest::test_overlapped_fixit_printing_utf8): Likewise.
+ (selftest::test_overlapped_fixit_printing_2): Likewise.
+ (selftest::test_tab_expansion): Likewise.
+ (selftest::test_escaping_bytes_1): New.
+ (selftest::test_escaping_bytes_2): New.
+ (selftest::diagnostic_show_locus_c_tests): Call the new tests.
+ * diagnostic.c (diagnostic_initialize): Initialize
+ context->escape_format.
+ (convert_column_unit): Update to use default character width policy.
+ (selftest::test_diagnostic_get_location_text): Likewise.
+ * diagnostic.h (enum diagnostics_escape_format): New enum.
+ (diagnostic_context::escape_format): New field.
+ * doc/invoke.texi (-fdiagnostics-escape-format=): New option.
+ (-fdiagnostics-format=): Add "escape-source" attribute to examples
+ of JSON output, and document it.
+ * input.c (location_compute_display_column): Pass in "policy"
+ rather than "tabstop", passing to
+ cpp_byte_column_to_display_column.
+ (selftest::test_cpp_utf8): Update to use cpp_char_column_policy.
+ * input.h (class cpp_char_column_policy): New forward decl.
+ (location_compute_display_column): Pass in "policy" rather than
+ "tabstop".
+ * opts.c (common_handle_option): Handle
+ OPT_fdiagnostics_escape_format_.
+ * selftest.c (temp_source_file::temp_source_file): New ctor
+ overload taking a size_t.
+ * selftest.h (temp_source_file::temp_source_file): Likewise.
+
+gcc/testsuite/ChangeLog:
+ * c-c++-common/diagnostic-format-json-1.c: Add regexp to consume
+ "escape-source" attribute.
+ * c-c++-common/diagnostic-format-json-2.c: Likewise.
+ * c-c++-common/diagnostic-format-json-3.c: Likewise.
+ * c-c++-common/diagnostic-format-json-4.c: Likewise, twice.
+ * c-c++-common/diagnostic-format-json-5.c: Likewise.
+ * gcc.dg/cpp/warn-normalized-4-bytes.c: New test.
+ * gcc.dg/cpp/warn-normalized-4-unicode.c: New test.
+ * gcc.dg/encoding-issues-bytes.c: New test.
+ * gcc.dg/encoding-issues-unicode.c: New test.
+ * gfortran.dg/diagnostic-format-json-1.F90: Add regexp to consume
+ "escape-source" attribute.
+ * gfortran.dg/diagnostic-format-json-2.F90: Likewise.
+ * gfortran.dg/diagnostic-format-json-3.F90: Likewise.
+
+libcpp/ChangeLog:
+ * charset.c (convert_escape): Use encoding_rich_location when
+ complaining about nonprintable unknown escape sequences.
+ (cpp_display_width_computation::::cpp_display_width_computation):
+ Pass in policy rather than tabstop.
+ (cpp_display_width_computation::process_next_codepoint): Add "out"
+ param and populate *out if non-NULL.
+ (cpp_display_width_computation::advance_display_cols): Pass NULL
+ to process_next_codepoint.
+ (cpp_byte_column_to_display_column): Pass in policy rather than
+ tabstop. Pass NULL to process_next_codepoint.
+ (cpp_display_column_to_byte_column): Pass in policy rather than
+ tabstop.
+ * errors.c (cpp_diagnostic_get_current_location): New function,
+ splitting out the logic from...
+ (cpp_diagnostic): ...here.
+ (cpp_warning_at): New function.
+ (cpp_pedwarning_at): New function.
+ * include/cpplib.h (cpp_warning_at): New decl for rich_location.
+ (cpp_pedwarning_at): Likewise.
+ (struct cpp_decoded_char): New.
+ (struct cpp_char_column_policy): New.
+ (cpp_display_width_computation::cpp_display_width_computation):
+ Replace "tabstop" param with "policy".
+ (cpp_display_width_computation::process_next_codepoint): Add "out"
+ param.
+ (cpp_display_width_computation::m_tabstop): Replace with...
+ (cpp_display_width_computation::m_policy): ...this.
+ (cpp_byte_column_to_display_column): Replace "tabstop" param with
+ "policy".
+ (cpp_display_width): Likewise.
+ (cpp_display_column_to_byte_column): Likewise.
+ * include/line-map.h (rich_location::escape_on_output_p): New.
+ (rich_location::set_escape_on_output): New.
+ (rich_location::m_escape_on_output): New.
+ * internal.h (cpp_diagnostic_get_current_location): New decl.
+ (class encoding_rich_location): New.
+ * lex.c (skip_whitespace): Use encoding_rich_location when
+ complaining about null characters.
+ (warn_about_normalization): Generate a source range when
+ complaining about improperly normalized tokens, rather than just a
+ point, and use encoding_rich_location so that the source code
+ is escaped on printing.
+ * line-map.c (rich_location::rich_location): Initialize
+ m_escape_on_output.
+
+Signed-off-by: David Malcolm <dmalcolm@redhat.com>
+
+CVE: CVE-2021-42574
+Upstream-Status: Backport [https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=bd5e882cf6e0def3dd1bc106075d59a303fe0d1e]
+Signed-off-by: Pgowda <pgowda.cve@gmail.com>
+
+---
+ gcc/c-family/c-lex.c | 6 +-
+ gcc/common.opt | 13 +
+ gcc/diagnostic-format-json.cc | 3 +
+ gcc/diagnostic-show-locus.c | 580 +++++++++++++++---
+ gcc/diagnostic.c | 10 +-
+ gcc/diagnostic.h | 18 +
+ gcc/doc/invoke.texi | 43 +-
+ gcc/input.c | 62 +-
+ gcc/input.h | 7 +-
+ gcc/opts.c | 4 +
+ gcc/selftest.c | 15 +
+ gcc/selftest.h | 2 +
+ .../c-c++-common/diagnostic-format-json-1.c | 1 +
+ .../c-c++-common/diagnostic-format-json-2.c | 1 +
+ .../c-c++-common/diagnostic-format-json-3.c | 1 +
+ .../c-c++-common/diagnostic-format-json-4.c | 2 +
+ .../c-c++-common/diagnostic-format-json-5.c | 1 +
+ .../gcc.dg/cpp/warn-normalized-4-bytes.c | 21 +
+ .../gcc.dg/cpp/warn-normalized-4-unicode.c | 19 +
+ gcc/testsuite/gcc.dg/encoding-issues-bytes.c | Bin 0 -> 595 bytes
+ .../gcc.dg/encoding-issues-unicode.c | Bin 0 -> 613 bytes
+ .../gfortran.dg/diagnostic-format-json-1.F90 | 1 +
+ .../gfortran.dg/diagnostic-format-json-2.F90 | 1 +
+ .../gfortran.dg/diagnostic-format-json-3.F90 | 1 +
+ libcpp/charset.c | 63 +-
+ libcpp/errors.c | 82 ++-
+ libcpp/include/cpplib.h | 76 ++-
+ libcpp/include/line-map.h | 13 +
+ libcpp/internal.h | 23 +
+ libcpp/lex.c | 38 +-
+ libcpp/line-map.c | 3 +-
+ 31 files changed, 942 insertions(+), 168 deletions(-)
+ create mode 100644 gcc/testsuite/gcc.dg/cpp/warn-normalized-4-bytes.c
+ create mode 100644 gcc/testsuite/gcc.dg/cpp/warn-normalized-4-unicode.c
+ create mode 100644 gcc/testsuite/gcc.dg/encoding-issues-bytes.c
+ create mode 100644 gcc/testsuite/gcc.dg/encoding-issues-unicode.c
+
+diff --git a/gcc/c-family/c-lex.c b/gcc/c-family/c-lex.c
+--- a/gcc/c-family/c-lex.c 2021-07-27 23:55:06.980283060 -0700
++++ b/gcc/c-family/c-lex.c 2021-12-14 01:16:01.541943272 -0800
+@@ -603,7 +603,11 @@ c_lex_with_flags (tree *value, location_
+ else if (ISGRAPH (c))
+ error_at (*loc, "stray %qc in program", (int) c);
+ else
+- error_at (*loc, "stray %<\\%o%> in program", (int) c);
++ {
++ rich_location rich_loc (line_table, *loc);
++ rich_loc.set_escape_on_output (true);
++ error_at (&rich_loc, "stray %<\\%o%> in program", (int) c);
++ }
+ }
+ goto retry;
+
+diff --git a/gcc/common.opt b/gcc/common.opt
+--- a/gcc/common.opt 2021-12-13 22:08:44.939137107 -0800
++++ b/gcc/common.opt 2021-12-14 01:16:01.541943272 -0800
+@@ -1348,6 +1348,10 @@ fdiagnostics-format=
+ Common Joined RejectNegative Enum(diagnostics_output_format)
+ -fdiagnostics-format=[text|json] Select output format.
+
++fdiagnostics-escape-format=
++Common Joined RejectNegative Enum(diagnostics_escape_format)
++-fdiagnostics-escape-format=[unicode|bytes] Select how to escape non-printable-ASCII bytes in the source for diagnostics that suggest it.
++
+ ; Required for these enum values.
+ SourceInclude
+ diagnostic.h
+@@ -1362,6 +1366,15 @@ EnumValue
+ Enum(diagnostics_column_unit) String(byte) Value(DIAGNOSTICS_COLUMN_UNIT_BYTE)
+
+ Enum
++Name(diagnostics_escape_format) Type(int)
++
++EnumValue
++Enum(diagnostics_escape_format) String(unicode) Value(DIAGNOSTICS_ESCAPE_FORMAT_UNICODE)
++
++EnumValue
++Enum(diagnostics_escape_format) String(bytes) Value(DIAGNOSTICS_ESCAPE_FORMAT_BYTES)
++
++Enum
+ Name(diagnostics_output_format) Type(int)
+
+ EnumValue
+diff --git a/gcc/diagnostic.c b/gcc/diagnostic.c
+--- a/gcc/diagnostic.c 2021-07-27 23:55:07.232286576 -0700
++++ b/gcc/diagnostic.c 2021-12-14 01:16:01.545943202 -0800
+@@ -230,6 +230,7 @@ diagnostic_initialize (diagnostic_contex
+ context->column_unit = DIAGNOSTICS_COLUMN_UNIT_DISPLAY;
+ context->column_origin = 1;
+ context->tabstop = 8;
++ context->escape_format = DIAGNOSTICS_ESCAPE_FORMAT_UNICODE;
+ context->edit_context_ptr = NULL;
+ context->diagnostic_group_nesting_depth = 0;
+ context->diagnostic_group_emission_count = 0;
+@@ -382,7 +383,10 @@ convert_column_unit (enum diagnostics_co
+ gcc_unreachable ();
+
+ case DIAGNOSTICS_COLUMN_UNIT_DISPLAY:
+- return location_compute_display_column (s, tabstop);
++ {
++ cpp_char_column_policy policy (tabstop, cpp_wcwidth);
++ return location_compute_display_column (s, policy);
++ }
+
+ case DIAGNOSTICS_COLUMN_UNIT_BYTE:
+ return s.column;
+@@ -2275,8 +2279,8 @@ test_diagnostic_get_location_text ()
+ const char *const content = "smile \xf0\x9f\x98\x82\n";
+ const int line_bytes = strlen (content) - 1;
+ const int def_tabstop = 8;
+- const int display_width = cpp_display_width (content, line_bytes,
+- def_tabstop);
++ const cpp_char_column_policy policy (def_tabstop, cpp_wcwidth);
++ const int display_width = cpp_display_width (content, line_bytes, policy);
+ ASSERT_EQ (line_bytes - 2, display_width);
+ temp_source_file tmp (SELFTEST_LOCATION, ".c", content);
+ const char *const fname = tmp.get_filename ();
+diff --git a/gcc/diagnostic-format-json.cc b/gcc/diagnostic-format-json.cc
+--- a/gcc/diagnostic-format-json.cc 2021-07-27 23:55:07.232286576 -0700
++++ b/gcc/diagnostic-format-json.cc 2021-12-14 01:16:01.541943272 -0800
+@@ -264,6 +264,9 @@ json_end_diagnostic (diagnostic_context
+ json::value *path_value = context->make_json_for_path (context, path);
+ diag_obj->set ("path", path_value);
+ }
++
++ diag_obj->set ("escape-source",
++ new json::literal (richloc->escape_on_output_p ()));
+ }
+
+ /* No-op implementation of "begin_group_cb" for JSON output. */
+diff --git a/gcc/diagnostic.h b/gcc/diagnostic.h
+--- a/gcc/diagnostic.h 2021-07-27 23:55:07.236286632 -0700
++++ b/gcc/diagnostic.h 2021-12-14 01:16:01.545943202 -0800
+@@ -38,6 +38,20 @@ enum diagnostics_column_unit
+ DIAGNOSTICS_COLUMN_UNIT_BYTE
+ };
+
++/* An enum for controlling how to print non-ASCII characters/bytes when
++ a diagnostic suggests escaping the source code on output. */
++
++enum diagnostics_escape_format
++{
++ /* Escape non-ASCII Unicode characters in the form <U+XXXX> and
++ non-UTF-8 bytes in the form <XX>. */
++ DIAGNOSTICS_ESCAPE_FORMAT_UNICODE,
++
++ /* Escape non-ASCII bytes in the form <XX> (thus showing the underlying
++ encoding of non-ASCII Unicode characters). */
++ DIAGNOSTICS_ESCAPE_FORMAT_BYTES
++};
++
+ /* Enum for overriding the standard output format. */
+
+ enum diagnostics_output_format
+@@ -320,6 +334,10 @@ struct diagnostic_context
+ /* The size of the tabstop for tab expansion. */
+ int tabstop;
+
++ /* How should non-ASCII/non-printable bytes be escaped when
++ a diagnostic suggests escaping the source code on output. */
++ enum diagnostics_escape_format escape_format;
++
+ /* If non-NULL, an edit_context to which fix-it hints should be
+ applied, for generating patches. */
+ edit_context *edit_context_ptr;
+diff --git a/gcc/diagnostic-show-locus.c b/gcc/diagnostic-show-locus.c
+--- a/gcc/diagnostic-show-locus.c 2021-07-27 23:55:07.232286576 -0700
++++ b/gcc/diagnostic-show-locus.c 2021-12-14 01:16:01.545943202 -0800
+@@ -175,10 +175,26 @@ enum column_unit {
+ class exploc_with_display_col : public expanded_location
+ {
+ public:
+- exploc_with_display_col (const expanded_location &exploc, int tabstop)
+- : expanded_location (exploc),
+- m_display_col (location_compute_display_column (exploc, tabstop))
+- {}
++ exploc_with_display_col (const expanded_location &exploc,
++ const cpp_char_column_policy &policy,
++ enum location_aspect aspect)
++ : expanded_location (exploc),
++ m_display_col (location_compute_display_column (exploc, policy))
++ {
++ if (exploc.column > 0)
++ {
++ /* m_display_col is now the final column of the byte.
++ If escaping has happened, we may want the first column instead. */
++ if (aspect != LOCATION_ASPECT_FINISH)
++ {
++ expanded_location prev_exploc (exploc);
++ prev_exploc.column--;
++ int prev_display_col
++ = (location_compute_display_column (prev_exploc, policy));
++ m_display_col = prev_display_col + 1;
++ }
++ }
++ }
+
+ int m_display_col;
+ };
+@@ -313,6 +329,31 @@ test_line_span ()
+
+ #endif /* #if CHECKING_P */
+
++/* A bundle of information containing how to print unicode
++ characters and bytes when quoting source code.
++
++ Provides a unified place to support escaping some subset
++ of characters to some format.
++
++ Extends char_column_policy; printing is split out to avoid
++ libcpp having to know about pretty_printer. */
++
++struct char_display_policy : public cpp_char_column_policy
++{
++ public:
++ char_display_policy (int tabstop,
++ int (*width_cb) (cppchar_t c),
++ void (*print_cb) (pretty_printer *pp,
++ const cpp_decoded_char &cp))
++ : cpp_char_column_policy (tabstop, width_cb),
++ m_print_cb (print_cb)
++ {
++ }
++
++ void (*m_print_cb) (pretty_printer *pp,
++ const cpp_decoded_char &cp);
++};
++
+ /* A class to control the overall layout when printing a diagnostic.
+
+ The layout is determined within the constructor.
+@@ -345,6 +386,8 @@ class layout
+
+ void print_line (linenum_type row);
+
++ void on_bad_codepoint (const char *ptr, cppchar_t ch, size_t ch_sz);
++
+ private:
+ bool will_show_line_p (linenum_type row) const;
+ void print_leading_fixits (linenum_type row);
+@@ -386,6 +429,7 @@ class layout
+ private:
+ diagnostic_context *m_context;
+ pretty_printer *m_pp;
++ char_display_policy m_policy;
+ location_t m_primary_loc;
+ exploc_with_display_col m_exploc;
+ colorizer m_colorizer;
+@@ -398,6 +442,7 @@ class layout
+ auto_vec <line_span> m_line_spans;
+ int m_linenum_width;
+ int m_x_offset_display;
++ bool m_escape_on_output;
+ };
+
+ /* Implementation of "class colorizer". */
+@@ -646,6 +691,11 @@ layout_range::intersects_line_p (linenum
+ /* Default for when we don't care what the tab expansion is set to. */
+ static const int def_tabstop = 8;
+
++static cpp_char_column_policy def_policy ()
++{
++ return cpp_char_column_policy (8, cpp_wcwidth);
++}
++
+ /* Create some expanded locations for testing layout_range. The filename
+ member of the explocs is set to the empty string. This member will only be
+ inspected by the calls to location_compute_display_column() made from the
+@@ -662,10 +712,13 @@ make_range (int start_line, int start_co
+ = {"", start_line, start_col, NULL, false};
+ const expanded_location finish_exploc
+ = {"", end_line, end_col, NULL, false};
+- return layout_range (exploc_with_display_col (start_exploc, def_tabstop),
+- exploc_with_display_col (finish_exploc, def_tabstop),
++ return layout_range (exploc_with_display_col (start_exploc, def_policy (),
++ LOCATION_ASPECT_START),
++ exploc_with_display_col (finish_exploc, def_policy (),
++ LOCATION_ASPECT_FINISH),
+ SHOW_RANGE_WITHOUT_CARET,
+- exploc_with_display_col (start_exploc, def_tabstop),
++ exploc_with_display_col (start_exploc, def_policy (),
++ LOCATION_ASPECT_CARET),
+ 0, NULL);
+ }
+
+@@ -959,6 +1012,164 @@ fixit_cmp (const void *p_a, const void *
+ return hint_a->get_start_loc () - hint_b->get_start_loc ();
+ }
+
++/* Callbacks for use when not escaping the source. */
++
++/* The default callback for char_column_policy::m_width_cb is cpp_wcwidth. */
++
++/* Callback for char_display_policy::m_print_cb for printing source chars
++ when not escaping the source. */
++
++static void
++default_print_decoded_ch (pretty_printer *pp,
++ const cpp_decoded_char &decoded_ch)
++{
++ for (const char *ptr = decoded_ch.m_start_byte;
++ ptr != decoded_ch.m_next_byte; ptr++)
++ {
++ if (*ptr == '\0' || *ptr == '\r')
++ {
++ pp_space (pp);
++ continue;
++ }
++
++ pp_character (pp, *ptr);
++ }
++}
++
++/* Callbacks for use with DIAGNOSTICS_ESCAPE_FORMAT_BYTES. */
++
++static const int width_per_escaped_byte = 4;
++
++/* Callback for char_column_policy::m_width_cb for determining the
++ display width when escaping with DIAGNOSTICS_ESCAPE_FORMAT_BYTES. */
++
++static int
++escape_as_bytes_width (cppchar_t ch)
++{
++ if (ch < 0x80 && ISPRINT (ch))
++ return cpp_wcwidth (ch);
++ else
++ {
++ if (ch <= 0x7F) return 1 * width_per_escaped_byte;
++ if (ch <= 0x7FF) return 2 * width_per_escaped_byte;
++ if (ch <= 0xFFFF) return 3 * width_per_escaped_byte;
++ return 4 * width_per_escaped_byte;
++ }
++}
++
++/* Callback for char_display_policy::m_print_cb for printing source chars
++ when escaping with DIAGNOSTICS_ESCAPE_FORMAT_BYTES. */
++
++static void
++escape_as_bytes_print (pretty_printer *pp,
++ const cpp_decoded_char &decoded_ch)
++{
++ if (!decoded_ch.m_valid_ch)
++ {
++ for (const char *iter = decoded_ch.m_start_byte;
++ iter != decoded_ch.m_next_byte; ++iter)
++ {
++ char buf[16];
++ sprintf (buf, "<%02x>", (unsigned char)*iter);
++ pp_string (pp, buf);
++ }
++ return;
++ }
++
++ cppchar_t ch = decoded_ch.m_ch;
++ if (ch < 0x80 && ISPRINT (ch))
++ pp_character (pp, ch);
++ else
++ {
++ for (const char *iter = decoded_ch.m_start_byte;
++ iter < decoded_ch.m_next_byte; ++iter)
++ {
++ char buf[16];
++ sprintf (buf, "<%02x>", (unsigned char)*iter);
++ pp_string (pp, buf);
++ }
++ }
++}
++
++/* Callbacks for use with DIAGNOSTICS_ESCAPE_FORMAT_UNICODE. */
++
++/* Callback for char_column_policy::m_width_cb for determining the
++ display width when escaping with DIAGNOSTICS_ESCAPE_FORMAT_UNICODE. */
++
++static int
++escape_as_unicode_width (cppchar_t ch)
++{
++ if (ch < 0x80 && ISPRINT (ch))
++ return cpp_wcwidth (ch);
++ else
++ {
++ // Width of "<U+%04x>"
++ if (ch > 0xfffff)
++ return 10;
++ else if (ch > 0xffff)
++ return 9;
++ else
++ return 8;
++ }
++}
++
++/* Callback for char_display_policy::m_print_cb for printing source chars
++ when escaping with DIAGNOSTICS_ESCAPE_FORMAT_UNICODE. */
++
++static void
++escape_as_unicode_print (pretty_printer *pp,
++ const cpp_decoded_char &decoded_ch)
++{
++ if (!decoded_ch.m_valid_ch)
++ {
++ escape_as_bytes_print (pp, decoded_ch);
++ return;
++ }
++
++ cppchar_t ch = decoded_ch.m_ch;
++ if (ch < 0x80 && ISPRINT (ch))
++ pp_character (pp, ch);
++ else
++ {
++ char buf[16];
++ sprintf (buf, "<U+%04X>", ch);
++ pp_string (pp, buf);
++ }
++}
++
++/* Populate a char_display_policy based on DC and RICHLOC. */
++
++static char_display_policy
++make_policy (const diagnostic_context &dc,
++ const rich_location &richloc)
++{
++ /* The default is to not escape non-ASCII bytes. */
++ char_display_policy result
++ (dc.tabstop, cpp_wcwidth, default_print_decoded_ch);
++
++ /* If the diagnostic suggests escaping non-ASCII bytes, then
++ use policy from user-supplied options. */
++ if (richloc.escape_on_output_p ())
++ {
++ result.m_undecoded_byte_width = width_per_escaped_byte;
++ switch (dc.escape_format)
++ {
++ default:
++ gcc_unreachable ();
++ case DIAGNOSTICS_ESCAPE_FORMAT_UNICODE:
++ result.m_width_cb = escape_as_unicode_width;
++ result.m_print_cb = escape_as_unicode_print;
++ break;
++ case DIAGNOSTICS_ESCAPE_FORMAT_BYTES:
++ result.m_width_cb = escape_as_bytes_width;
++ result.m_print_cb = escape_as_bytes_print;
++ break;
++ }
++ }
++
++ return result;
++}
++
+ /* Implementation of class layout. */
+
+ /* Constructor for class layout.
+@@ -975,8 +1186,10 @@ layout::layout (diagnostic_context * con
+ diagnostic_t diagnostic_kind)
+ : m_context (context),
+ m_pp (context->printer),
++ m_policy (make_policy (*context, *richloc)),
+ m_primary_loc (richloc->get_range (0)->m_loc),
+- m_exploc (richloc->get_expanded_location (0), context->tabstop),
++ m_exploc (richloc->get_expanded_location (0), m_policy,
++ LOCATION_ASPECT_CARET),
+ m_colorizer (context, diagnostic_kind),
+ m_colorize_source_p (context->colorize_source_p),
+ m_show_labels_p (context->show_labels_p),
+@@ -986,7 +1199,8 @@ layout::layout (diagnostic_context * con
+ m_fixit_hints (richloc->get_num_fixit_hints ()),
+ m_line_spans (1 + richloc->get_num_locations ()),
+ m_linenum_width (0),
+- m_x_offset_display (0)
++ m_x_offset_display (0),
++ m_escape_on_output (richloc->escape_on_output_p ())
+ {
+ for (unsigned int idx = 0; idx < richloc->get_num_locations (); idx++)
+ {
+@@ -1072,10 +1286,13 @@ layout::maybe_add_location_range (const
+
+ /* Everything is now known to be in the correct source file,
+ but it may require further sanitization. */
+- layout_range ri (exploc_with_display_col (start, m_context->tabstop),
+- exploc_with_display_col (finish, m_context->tabstop),
++ layout_range ri (exploc_with_display_col (start, m_policy,
++ LOCATION_ASPECT_START),
++ exploc_with_display_col (finish, m_policy,
++ LOCATION_ASPECT_FINISH),
+ loc_range->m_range_display_kind,
+- exploc_with_display_col (caret, m_context->tabstop),
++ exploc_with_display_col (caret, m_policy,
++ LOCATION_ASPECT_CARET),
+ original_idx, loc_range->m_label);
+
+ /* If we have a range that finishes before it starts (perhaps
+@@ -1409,7 +1626,7 @@ layout::calculate_x_offset_display ()
+ = get_line_bytes_without_trailing_whitespace (line.get_buffer (),
+ line.length ());
+ int eol_display_column
+- = cpp_display_width (line.get_buffer (), line_bytes, m_context->tabstop);
++ = cpp_display_width (line.get_buffer (), line_bytes, m_policy);
+ if (caret_display_column > eol_display_column
+ || !caret_display_column)
+ {
+@@ -1488,7 +1705,7 @@ layout::print_source_line (linenum_type
+ /* This object helps to keep track of which display column we are at, which is
+ necessary for computing the line bounds in display units, for doing
+ tab expansion, and for implementing m_x_offset_display. */
+- cpp_display_width_computation dw (line, line_bytes, m_context->tabstop);
++ cpp_display_width_computation dw (line, line_bytes, m_policy);
+
+ /* Skip the first m_x_offset_display display columns. In case the leading
+ portion that will be skipped ends with a character with wcwidth > 1, then
+@@ -1536,7 +1753,8 @@ layout::print_source_line (linenum_type
+ tabs and replacing some control bytes with spaces as necessary. */
+ const char *c = dw.next_byte ();
+ const int start_disp_col = dw.display_cols_processed () + 1;
+- const int this_display_width = dw.process_next_codepoint ();
++ cpp_decoded_char cp;
++ const int this_display_width = dw.process_next_codepoint (&cp);
+ if (*c == '\t')
+ {
+ /* The returned display width is the number of spaces into which the
+@@ -1545,15 +1763,6 @@ layout::print_source_line (linenum_type
+ pp_space (m_pp);
+ continue;
+ }
+- if (*c == '\0' || *c == '\r')
+- {
+- /* cpp_wcwidth() promises to return 1 for all control bytes, and we
+- want to output these as a single space too, so this case is
+- actually the same as the '\t' case. */
+- gcc_assert (this_display_width == 1);
+- pp_space (m_pp);
+- continue;
+- }
+
+ /* We have a (possibly multibyte) character to output; update the line
+ bounds if it is not whitespace. */
+@@ -1565,7 +1774,8 @@ layout::print_source_line (linenum_type
+ }
+
+ /* Output the character. */
+- while (c != dw.next_byte ()) pp_character (m_pp, *c++);
++ m_policy.m_print_cb (m_pp, cp);
++ c = dw.next_byte ();
+ }
+ print_newline ();
+ return lbounds;
+@@ -1664,14 +1874,14 @@ layout::print_annotation_line (linenum_t
+ class line_label
+ {
+ public:
+- line_label (diagnostic_context *context, int state_idx, int column,
++ line_label (const cpp_char_column_policy &policy,
++ int state_idx, int column,
+ label_text text)
+ : m_state_idx (state_idx), m_column (column),
+ m_text (text), m_label_line (0), m_has_vbar (true)
+ {
+ const int bytes = strlen (text.m_buffer);
+- m_display_width
+- = cpp_display_width (text.m_buffer, bytes, context->tabstop);
++ m_display_width = cpp_display_width (text.m_buffer, bytes, policy);
+ }
+
+ /* Sorting is primarily by column, then by state index. */
+@@ -1731,7 +1941,7 @@ layout::print_any_labels (linenum_type r
+ if (text.m_buffer == NULL)
+ continue;
+
+- labels.safe_push (line_label (m_context, i, disp_col, text));
++ labels.safe_push (line_label (m_policy, i, disp_col, text));
+ }
+ }
+
+@@ -2011,7 +2221,7 @@ public:
+
+ /* Get the range of bytes or display columns that HINT would affect. */
+ static column_range
+-get_affected_range (diagnostic_context *context,
++get_affected_range (const cpp_char_column_policy &policy,
+ const fixit_hint *hint, enum column_unit col_unit)
+ {
+ expanded_location exploc_start = expand_location (hint->get_start_loc ());
+@@ -2022,13 +2232,11 @@ get_affected_range (diagnostic_context *
+ int finish_column;
+ if (col_unit == CU_DISPLAY_COLS)
+ {
+- start_column
+- = location_compute_display_column (exploc_start, context->tabstop);
++ start_column = location_compute_display_column (exploc_start, policy);
+ if (hint->insertion_p ())
+ finish_column = start_column - 1;
+ else
+- finish_column
+- = location_compute_display_column (exploc_finish, context->tabstop);
++ finish_column = location_compute_display_column (exploc_finish, policy);
+ }
+ else
+ {
+@@ -2041,12 +2249,13 @@ get_affected_range (diagnostic_context *
+ /* Get the range of display columns that would be printed for HINT. */
+
+ static column_range
+-get_printed_columns (diagnostic_context *context, const fixit_hint *hint)
++get_printed_columns (const cpp_char_column_policy &policy,
++ const fixit_hint *hint)
+ {
+ expanded_location exploc = expand_location (hint->get_start_loc ());
+- int start_column = location_compute_display_column (exploc, context->tabstop);
++ int start_column = location_compute_display_column (exploc, policy);
+ int hint_width = cpp_display_width (hint->get_string (), hint->get_length (),
+- context->tabstop);
++ policy);
+ int final_hint_column = start_column + hint_width - 1;
+ if (hint->insertion_p ())
+ {
+@@ -2056,8 +2265,7 @@ get_printed_columns (diagnostic_context
+ {
+ exploc = expand_location (hint->get_next_loc ());
+ --exploc.column;
+- int finish_column
+- = location_compute_display_column (exploc, context->tabstop);
++ int finish_column = location_compute_display_column (exploc, policy);
+ return column_range (start_column,
+ MAX (finish_column, final_hint_column));
+ }
+@@ -2075,13 +2283,13 @@ public:
+ column_range affected_columns,
+ column_range printed_columns,
+ const char *new_text, size_t new_text_len,
+- int tabstop)
++ const cpp_char_column_policy &policy)
+ : m_affected_bytes (affected_bytes),
+ m_affected_columns (affected_columns),
+ m_printed_columns (printed_columns),
+ m_text (xstrdup (new_text)),
+ m_byte_length (new_text_len),
+- m_tabstop (tabstop),
++ m_policy (policy),
+ m_alloc_sz (new_text_len + 1)
+ {
+ compute_display_cols ();
+@@ -2099,7 +2307,7 @@ public:
+
+ void compute_display_cols ()
+ {
+- m_display_cols = cpp_display_width (m_text, m_byte_length, m_tabstop);
++ m_display_cols = cpp_display_width (m_text, m_byte_length, m_policy);
+ }
+
+ void overwrite (int dst_offset, const char_span &src_span)
+@@ -2127,7 +2335,7 @@ public:
+ char *m_text;
+ size_t m_byte_length; /* Not including null-terminator. */
+ int m_display_cols;
+- int m_tabstop;
++ const cpp_char_column_policy &m_policy;
+ size_t m_alloc_sz;
+ };
+
+@@ -2163,15 +2371,16 @@ correction::ensure_terminated ()
+ class line_corrections
+ {
+ public:
+- line_corrections (diagnostic_context *context, const char *filename,
++ line_corrections (const char_display_policy &policy,
++ const char *filename,
+ linenum_type row)
+- : m_context (context), m_filename (filename), m_row (row)
++ : m_policy (policy), m_filename (filename), m_row (row)
+ {}
+ ~line_corrections ();
+
+ void add_hint (const fixit_hint *hint);
+
+- diagnostic_context *m_context;
++ const char_display_policy &m_policy;
+ const char *m_filename;
+ linenum_type m_row;
+ auto_vec <correction *> m_corrections;
+@@ -2217,10 +2426,10 @@ source_line::source_line (const char *fi
+ void
+ line_corrections::add_hint (const fixit_hint *hint)
+ {
+- column_range affected_bytes = get_affected_range (m_context, hint, CU_BYTES);
+- column_range affected_columns = get_affected_range (m_context, hint,
++ column_range affected_bytes = get_affected_range (m_policy, hint, CU_BYTES);
++ column_range affected_columns = get_affected_range (m_policy, hint,
+ CU_DISPLAY_COLS);
+- column_range printed_columns = get_printed_columns (m_context, hint);
++ column_range printed_columns = get_printed_columns (m_policy, hint);
+
+ /* Potentially consolidate. */
+ if (!m_corrections.is_empty ())
+@@ -2289,7 +2498,7 @@ line_corrections::add_hint (const fixit_
+ printed_columns,
+ hint->get_string (),
+ hint->get_length (),
+- m_context->tabstop));
++ m_policy));
+ }
+
+ /* If there are any fixit hints on source line ROW, print them.
+@@ -2303,7 +2512,7 @@ layout::print_trailing_fixits (linenum_t
+ {
+ /* Build a list of correction instances for the line,
+ potentially consolidating hints (for the sake of readability). */
+- line_corrections corrections (m_context, m_exploc.file, row);
++ line_corrections corrections (m_policy, m_exploc.file, row);
+ for (unsigned int i = 0; i < m_fixit_hints.length (); i++)
+ {
+ const fixit_hint *hint = m_fixit_hints[i];
+@@ -2646,6 +2855,59 @@ namespace selftest {
+
+ /* Selftests for diagnostic_show_locus. */
+
++/* Verify that cpp_display_width correctly handles escaping. */
++
++static void
++test_display_widths ()
++{
++ gcc_rich_location richloc (UNKNOWN_LOCATION);
++
++ /* U+03C0 "GREEK SMALL LETTER PI". */
++ const char *pi = "\xCF\x80";
++ /* U+1F642 "SLIGHTLY SMILING FACE". */
++ const char *emoji = "\xF0\x9F\x99\x82";
++ /* Stray trailing byte of a UTF-8 character. */
++ const char *stray = "\xBF";
++ /* U+10FFFF. */
++ const char *max_codepoint = "\xF4\x8F\xBF\xBF";
++
++ /* No escaping. */
++ {
++ test_diagnostic_context dc;
++ char_display_policy policy (make_policy (dc, richloc));
++ ASSERT_EQ (cpp_display_width (pi, strlen (pi), policy), 1);
++ ASSERT_EQ (cpp_display_width (emoji, strlen (emoji), policy), 2);
++ ASSERT_EQ (cpp_display_width (stray, strlen (stray), policy), 1);
++ /* Don't check width of U+10FFFF; it's in a private use plane. */
++ }
++
++ richloc.set_escape_on_output (true);
++
++ {
++ test_diagnostic_context dc;
++ dc.escape_format = DIAGNOSTICS_ESCAPE_FORMAT_UNICODE;
++ char_display_policy policy (make_policy (dc, richloc));
++ ASSERT_EQ (cpp_display_width (pi, strlen (pi), policy), 8);
++ ASSERT_EQ (cpp_display_width (emoji, strlen (emoji), policy), 9);
++ ASSERT_EQ (cpp_display_width (stray, strlen (stray), policy), 4);
++ ASSERT_EQ (cpp_display_width (max_codepoint, strlen (max_codepoint),
++ policy),
++ strlen ("<U+10FFFF>"));
++ }
++
++ {
++ test_diagnostic_context dc;
++ dc.escape_format = DIAGNOSTICS_ESCAPE_FORMAT_BYTES;
++ char_display_policy policy (make_policy (dc, richloc));
++ ASSERT_EQ (cpp_display_width (pi, strlen (pi), policy), 8);
++ ASSERT_EQ (cpp_display_width (emoji, strlen (emoji), policy), 16);
++ ASSERT_EQ (cpp_display_width (stray, strlen (stray), policy), 4);
++ ASSERT_EQ (cpp_display_width (max_codepoint, strlen (max_codepoint),
++ policy),
++ 16);
++ }
++}
++
+ /* For precise tests of the layout, make clear where the source line will
+ start. test_left_margin sets the total byte count from the left side of the
+ screen to the start of source lines, after the line number and the separator,
+@@ -2715,10 +2977,10 @@ test_layout_x_offset_display_utf8 (const
+ char_span lspan = location_get_source_line (tmp.get_filename (), 1);
+ ASSERT_EQ (line_display_cols,
+ cpp_display_width (lspan.get_buffer (), lspan.length (),
+- def_tabstop));
++ def_policy ()));
+ ASSERT_EQ (line_display_cols,
+ location_compute_display_column (expand_location (line_end),
+- def_tabstop));
++ def_policy ()));
+ ASSERT_EQ (0, memcmp (lspan.get_buffer () + (emoji_col - 1),
+ "\xf0\x9f\x98\x82\xf0\x9f\x98\x82", 8));
+
+@@ -2866,12 +3128,13 @@ test_layout_x_offset_display_tab (const
+ ASSERT_EQ ('\t', *(lspan.get_buffer () + (tab_col - 1)));
+ for (int tabstop = 1; tabstop != num_tabstops; ++tabstop)
+ {
++ cpp_char_column_policy policy (tabstop, cpp_wcwidth);
+ ASSERT_EQ (line_bytes + extra_width[tabstop],
+ cpp_display_width (lspan.get_buffer (), lspan.length (),
+- tabstop));
++ policy));
+ ASSERT_EQ (line_bytes + extra_width[tabstop],
+ location_compute_display_column (expand_location (line_end),
+- tabstop));
++ policy));
+ }
+
+ /* Check that the tab is expanded to the expected number of spaces. */
+@@ -4003,6 +4266,43 @@ test_one_liner_labels_utf8 ()
+ " bb\xf0\x9f\x98\x82\xf0\x9f\x98\x82\n",
+ pp_formatted_text (dc.printer));
+ }
++
++ /* Example of escaping the source lines. */
++ {
++ text_range_label label0 ("label 0\xf0\x9f\x98\x82");
++ text_range_label label1 ("label 1\xcf\x80");
++ text_range_label label2 ("label 2\xcf\x80");
++ gcc_rich_location richloc (foo, &label0);
++ richloc.add_range (bar, SHOW_RANGE_WITHOUT_CARET, &label1);
++ richloc.add_range (field, SHOW_RANGE_WITHOUT_CARET, &label2);
++ richloc.set_escape_on_output (true);
++
++ {
++ test_diagnostic_context dc;
++ dc.escape_format = DIAGNOSTICS_ESCAPE_FORMAT_UNICODE;
++ diagnostic_show_locus (&dc, &richloc, DK_ERROR);
++ ASSERT_STREQ (" <U+1F602>_foo = <U+03C0>_bar.<U+1F602>_field<U+03C0>;\n"
++ " ^~~~~~~~~~~~~ ~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~\n"
++ " | | |\n"
++ " | | label 2\xcf\x80\n"
++ " | label 1\xcf\x80\n"
++ " label 0\xf0\x9f\x98\x82\n",
++ pp_formatted_text (dc.printer));
++ }
++ {
++ test_diagnostic_context dc;
++ dc.escape_format = DIAGNOSTICS_ESCAPE_FORMAT_BYTES;
++ diagnostic_show_locus (&dc, &richloc, DK_ERROR);
++ ASSERT_STREQ
++ (" <f0><9f><98><82>_foo = <cf><80>_bar.<f0><9f><98><82>_field<cf><80>;\n"
++ " ^~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n"
++ " | | |\n"
++ " | | label 2\xcf\x80\n"
++ " | label 1\xcf\x80\n"
++ " label 0\xf0\x9f\x98\x82\n",
++ pp_formatted_text (dc.printer));
++ }
++ }
+ }
+
+ /* Make sure that colorization codes don't interrupt a multibyte
+@@ -4057,9 +4357,9 @@ test_diagnostic_show_locus_one_liner_utf
+
+ char_span lspan = location_get_source_line (tmp.get_filename (), 1);
+ ASSERT_EQ (25, cpp_display_width (lspan.get_buffer (), lspan.length (),
+- def_tabstop));
++ def_policy ()));
+ ASSERT_EQ (25, location_compute_display_column (expand_location (line_end),
+- def_tabstop));
++ def_policy ()));
+
+ test_one_liner_simple_caret_utf8 ();
+ test_one_liner_caret_and_range_utf8 ();
+@@ -4445,30 +4745,31 @@ test_overlapped_fixit_printing (const li
+ pp_formatted_text (dc.printer));
+
+ /* Unit-test the line_corrections machinery. */
++ char_display_policy policy (make_policy (dc, richloc));
+ ASSERT_EQ (3, richloc.get_num_fixit_hints ());
+ const fixit_hint *hint_0 = richloc.get_fixit_hint (0);
+ ASSERT_EQ (column_range (12, 12),
+- get_affected_range (&dc, hint_0, CU_BYTES));
++ get_affected_range (policy, hint_0, CU_BYTES));
+ ASSERT_EQ (column_range (12, 12),
+- get_affected_range (&dc, hint_0, CU_DISPLAY_COLS));
+- ASSERT_EQ (column_range (12, 22), get_printed_columns (&dc, hint_0));
++ get_affected_range (policy, hint_0, CU_DISPLAY_COLS));
++ ASSERT_EQ (column_range (12, 22), get_printed_columns (policy, hint_0));
+ const fixit_hint *hint_1 = richloc.get_fixit_hint (1);
+ ASSERT_EQ (column_range (18, 18),
+- get_affected_range (&dc, hint_1, CU_BYTES));
++ get_affected_range (policy, hint_1, CU_BYTES));
+ ASSERT_EQ (column_range (18, 18),
+- get_affected_range (&dc, hint_1, CU_DISPLAY_COLS));
+- ASSERT_EQ (column_range (18, 20), get_printed_columns (&dc, hint_1));
++ get_affected_range (policy, hint_1, CU_DISPLAY_COLS));
++ ASSERT_EQ (column_range (18, 20), get_printed_columns (policy, hint_1));
+ const fixit_hint *hint_2 = richloc.get_fixit_hint (2);
+ ASSERT_EQ (column_range (29, 28),
+- get_affected_range (&dc, hint_2, CU_BYTES));
++ get_affected_range (policy, hint_2, CU_BYTES));
+ ASSERT_EQ (column_range (29, 28),
+- get_affected_range (&dc, hint_2, CU_DISPLAY_COLS));
+- ASSERT_EQ (column_range (29, 29), get_printed_columns (&dc, hint_2));
++ get_affected_range (policy, hint_2, CU_DISPLAY_COLS));
++ ASSERT_EQ (column_range (29, 29), get_printed_columns (policy, hint_2));
+
+ /* Add each hint in turn to a line_corrections instance,
+ and verify that they are consolidated into one correction instance
+ as expected. */
+- line_corrections lc (&dc, tmp.get_filename (), 1);
++ line_corrections lc (policy, tmp.get_filename (), 1);
+
+ /* The first replace hint by itself. */
+ lc.add_hint (hint_0);
+@@ -4660,30 +4961,31 @@ test_overlapped_fixit_printing_utf8 (con
+ pp_formatted_text (dc.printer));
+
+ /* Unit-test the line_corrections machinery. */
++ char_display_policy policy (make_policy (dc, richloc));
+ ASSERT_EQ (3, richloc.get_num_fixit_hints ());
+ const fixit_hint *hint_0 = richloc.get_fixit_hint (0);
+ ASSERT_EQ (column_range (14, 14),
+- get_affected_range (&dc, hint_0, CU_BYTES));
++ get_affected_range (policy, hint_0, CU_BYTES));
+ ASSERT_EQ (column_range (12, 12),
+- get_affected_range (&dc, hint_0, CU_DISPLAY_COLS));
+- ASSERT_EQ (column_range (12, 22), get_printed_columns (&dc, hint_0));
++ get_affected_range (policy, hint_0, CU_DISPLAY_COLS));
++ ASSERT_EQ (column_range (12, 22), get_printed_columns (policy, hint_0));
+ const fixit_hint *hint_1 = richloc.get_fixit_hint (1);
+ ASSERT_EQ (column_range (22, 22),
+- get_affected_range (&dc, hint_1, CU_BYTES));
++ get_affected_range (policy, hint_1, CU_BYTES));
+ ASSERT_EQ (column_range (18, 18),
+- get_affected_range (&dc, hint_1, CU_DISPLAY_COLS));
+- ASSERT_EQ (column_range (18, 20), get_printed_columns (&dc, hint_1));
++ get_affected_range (policy, hint_1, CU_DISPLAY_COLS));
++ ASSERT_EQ (column_range (18, 20), get_printed_columns (policy, hint_1));
+ const fixit_hint *hint_2 = richloc.get_fixit_hint (2);
+ ASSERT_EQ (column_range (35, 34),
+- get_affected_range (&dc, hint_2, CU_BYTES));
++ get_affected_range (policy, hint_2, CU_BYTES));
+ ASSERT_EQ (column_range (30, 29),
+- get_affected_range (&dc, hint_2, CU_DISPLAY_COLS));
+- ASSERT_EQ (column_range (30, 30), get_printed_columns (&dc, hint_2));
++ get_affected_range (policy, hint_2, CU_DISPLAY_COLS));
++ ASSERT_EQ (column_range (30, 30), get_printed_columns (policy, hint_2));
+
+ /* Add each hint in turn to a line_corrections instance,
+ and verify that they are consolidated into one correction instance
+ as expected. */
+- line_corrections lc (&dc, tmp.get_filename (), 1);
++ line_corrections lc (policy, tmp.get_filename (), 1);
+
+ /* The first replace hint by itself. */
+ lc.add_hint (hint_0);
+@@ -4877,15 +5179,16 @@ test_overlapped_fixit_printing_2 (const
+ richloc.add_fixit_insert_before (col_21, "}");
+
+ /* These fixits should be accepted; they can't be consolidated. */
++ char_display_policy policy (make_policy (dc, richloc));
+ ASSERT_EQ (2, richloc.get_num_fixit_hints ());
+ const fixit_hint *hint_0 = richloc.get_fixit_hint (0);
+ ASSERT_EQ (column_range (23, 22),
+- get_affected_range (&dc, hint_0, CU_BYTES));
+- ASSERT_EQ (column_range (23, 23), get_printed_columns (&dc, hint_0));
++ get_affected_range (policy, hint_0, CU_BYTES));
++ ASSERT_EQ (column_range (23, 23), get_printed_columns (policy, hint_0));
+ const fixit_hint *hint_1 = richloc.get_fixit_hint (1);
+ ASSERT_EQ (column_range (21, 20),
+- get_affected_range (&dc, hint_1, CU_BYTES));
+- ASSERT_EQ (column_range (21, 21), get_printed_columns (&dc, hint_1));
++ get_affected_range (policy, hint_1, CU_BYTES));
++ ASSERT_EQ (column_range (21, 21), get_printed_columns (policy, hint_1));
+
+ /* Verify that they're printed correctly. */
+ diagnostic_show_locus (&dc, &richloc, DK_ERROR);
+@@ -5152,10 +5455,11 @@ test_tab_expansion (const line_table_cas
+ ....................123 45678901234 56789012345 columns */
+
+ const int tabstop = 8;
++ cpp_char_column_policy policy (tabstop, cpp_wcwidth);
+ const int first_non_ws_byte_col = 7;
+ const int right_quote_byte_col = 15;
+ const int last_byte_col = 25;
+- ASSERT_EQ (35, cpp_display_width (content, last_byte_col, tabstop));
++ ASSERT_EQ (35, cpp_display_width (content, last_byte_col, policy));
+
+ temp_source_file tmp (SELFTEST_LOCATION, ".c", content);
+ line_table_test ltt (case_);
+@@ -5198,6 +5502,114 @@ test_tab_expansion (const line_table_cas
+ }
+ }
+
++/* Verify that the escaping machinery can cope with a variety of different
++ invalid bytes. */
++
++static void
++test_escaping_bytes_1 (const line_table_case &case_)
++{
++ const char content[] = "before\0\1\2\3\r\x80\xff""after\n";
++ const size_t sz = sizeof (content);
++ temp_source_file tmp (SELFTEST_LOCATION, ".c", content, sz);
++ line_table_test ltt (case_);
++ const line_map_ordinary *ord_map = linemap_check_ordinary
++ (linemap_add (line_table, LC_ENTER, false, tmp.get_filename (), 0));
++ linemap_line_start (line_table, 1, 100);
++
++ location_t finish
++ = linemap_position_for_line_and_column (line_table, ord_map, 1,
++ strlen (content));
++
++ if (finish > LINE_MAP_MAX_LOCATION_WITH_COLS)
++ return;
++
++ /* Locations of the NUL and \r bytes. */
++ location_t nul_loc
++ = linemap_position_for_line_and_column (line_table, ord_map, 1, 7);
++ location_t r_loc
++ = linemap_position_for_line_and_column (line_table, ord_map, 1, 11);
++ gcc_rich_location richloc (nul_loc);
++ richloc.add_range (r_loc);
++
++ {
++ test_diagnostic_context dc;
++ diagnostic_show_locus (&dc, &richloc, DK_ERROR);
++ ASSERT_STREQ (" before \1\2\3 \x80\xff""after\n"
++ " ^ ~\n",
++ pp_formatted_text (dc.printer));
++ }
++ richloc.set_escape_on_output (true);
++ {
++ test_diagnostic_context dc;
++ dc.escape_format = DIAGNOSTICS_ESCAPE_FORMAT_UNICODE;
++ diagnostic_show_locus (&dc, &richloc, DK_ERROR);
++ ASSERT_STREQ
++ (" before<U+0000><U+0001><U+0002><U+0003><U+000D><80><ff>after\n"
++ " ^~~~~~~~ ~~~~~~~~\n",
++ pp_formatted_text (dc.printer));
++ }
++ {
++ test_diagnostic_context dc;
++ dc.escape_format = DIAGNOSTICS_ESCAPE_FORMAT_BYTES;
++ diagnostic_show_locus (&dc, &richloc, DK_ERROR);
++ ASSERT_STREQ (" before<00><01><02><03><0d><80><ff>after\n"
++ " ^~~~ ~~~~\n",
++ pp_formatted_text (dc.printer));
++ }
++}
++
++/* As above, but verify that we handle the initial byte of a line
++ correctly. */
++
++static void
++test_escaping_bytes_2 (const line_table_case &case_)
++{
++ const char content[] = "\0after\n";
++ const size_t sz = sizeof (content);
++ temp_source_file tmp (SELFTEST_LOCATION, ".c", content, sz);
++ line_table_test ltt (case_);
++ const line_map_ordinary *ord_map = linemap_check_ordinary
++ (linemap_add (line_table, LC_ENTER, false, tmp.get_filename (), 0));
++ linemap_line_start (line_table, 1, 100);
++
++ location_t finish
++ = linemap_position_for_line_and_column (line_table, ord_map, 1,
++ strlen (content));
++
++ if (finish > LINE_MAP_MAX_LOCATION_WITH_COLS)
++ return;
++
++ /* Location of the NUL byte. */
++ location_t nul_loc
++ = linemap_position_for_line_and_column (line_table, ord_map, 1, 1);
++ gcc_rich_location richloc (nul_loc);
++
++ {
++ test_diagnostic_context dc;
++ diagnostic_show_locus (&dc, &richloc, DK_ERROR);
++ ASSERT_STREQ (" after\n"
++ " ^\n",
++ pp_formatted_text (dc.printer));
++ }
++ richloc.set_escape_on_output (true);
++ {
++ test_diagnostic_context dc;
++ dc.escape_format = DIAGNOSTICS_ESCAPE_FORMAT_UNICODE;
++ diagnostic_show_locus (&dc, &richloc, DK_ERROR);
++ ASSERT_STREQ (" <U+0000>after\n"
++ " ^~~~~~~~\n",
++ pp_formatted_text (dc.printer));
++ }
++ {
++ test_diagnostic_context dc;
++ dc.escape_format = DIAGNOSTICS_ESCAPE_FORMAT_BYTES;
++ diagnostic_show_locus (&dc, &richloc, DK_ERROR);
++ ASSERT_STREQ (" <00>after\n"
++ " ^~~~\n",
++ pp_formatted_text (dc.printer));
++ }
++}
++
+ /* Verify that line numbers are correctly printed for the case of
+ a multiline range in which the width of the line numbers changes
+ (e.g. from "9" to "10"). */
+@@ -5254,6 +5666,8 @@ diagnostic_show_locus_c_tests ()
+ test_layout_range_for_single_line ();
+ test_layout_range_for_multiple_lines ();
+
++ test_display_widths ();
++
+ for_each_line_table_case (test_layout_x_offset_display_utf8);
+ for_each_line_table_case (test_layout_x_offset_display_tab);
+
+@@ -5274,6 +5688,8 @@ diagnostic_show_locus_c_tests ()
+ for_each_line_table_case (test_fixit_replace_containing_newline);
+ for_each_line_table_case (test_fixit_deletion_affecting_newline);
+ for_each_line_table_case (test_tab_expansion);
++ for_each_line_table_case (test_escaping_bytes_1);
++ for_each_line_table_case (test_escaping_bytes_2);
+
+ test_line_numbers_multiline_range ();
+ }
+diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
+--- a/gcc/doc/invoke.texi 2021-12-13 23:23:05.764437151 -0800
++++ b/gcc/doc/invoke.texi 2021-12-14 01:16:01.553943061 -0800
+@@ -312,7 +312,8 @@ Objective-C and Objective-C++ Dialects}.
+ -fdiagnostics-show-path-depths @gol
+ -fno-show-column @gol
+ -fdiagnostics-column-unit=@r{[}display@r{|}byte@r{]} @gol
+--fdiagnostics-column-origin=@var{origin}}
++-fdiagnostics-column-origin=@var{origin} @gol
++-fdiagnostics-escape-format=@r{[}unicode@r{|}bytes@r{]}}
+
+ @item Warning Options
+ @xref{Warning Options,,Options to Request or Suppress Warnings}.
+@@ -5083,6 +5084,38 @@ first column. The default value of 1 co
+ behavior and to the GNU style guide. Some utilities may perform better with an
+ origin of 0; any non-negative value may be specified.
+
++@item -fdiagnostics-escape-format=@var{FORMAT}
++@opindex fdiagnostics-escape-format
++When GCC prints pertinent source lines for a diagnostic it normally attempts
++to print the source bytes directly. However, some diagnostics relate to encoding
++issues in the source file, such as malformed UTF-8, or issues with Unicode
++normalization. These diagnostics are flagged so that GCC will escape bytes
++that are not printable ASCII when printing their pertinent source lines.
++
++This option controls how such bytes should be escaped.
++
++The default @var{FORMAT}, @samp{unicode} displays Unicode characters that
++are not printable ASCII in the form @samp{<U+XXXX>}, and bytes that do not
++correspond to a Unicode character validly-encoded in UTF-8-encoded will be
++displayed as hexadecimal in the form @samp{<XX>}.
++
++For example, a source line containing the string @samp{before} followed by the
++Unicode character U+03C0 (``GREEK SMALL LETTER PI'', with UTF-8 encoding
++0xCF 0x80) followed by the byte 0xBF (a stray UTF-8 trailing byte), followed by
++the string @samp{after} will be printed for such a diagnostic as:
++
++@smallexample
++ before<U+03C0><BF>after
++@end smallexample
++
++Setting @var{FORMAT} to @samp{bytes} will display all non-printable-ASCII bytes
++in the form @samp{<XX>}, thus showing the underlying encoding of non-ASCII
++Unicode characters. For the example above, the following will be printed:
++
++@smallexample
++ before<CF><80><BF>after
++@end smallexample
++
+ @item -fdiagnostics-format=@var{FORMAT}
+ @opindex fdiagnostics-format
+ Select a different format for printing diagnostics.
+@@ -5150,9 +5183,11 @@ might be printed in JSON form (after for
+ @}
+ @}
+ ],
++ "escape-source": false,
+ "message": "...this statement, but the latter is @dots{}"
+ @}
+ ]
++ "escape-source": false,
+ "column-origin": 1,
+ @},
+ @dots{}
+@@ -5239,6 +5274,7 @@ of the expression, which have labels. I
+ "label": "T @{aka struct t@}"
+ @}
+ ],
++ "escape-source": false,
+ "message": "invalid operands to binary + @dots{}"
+ @}
+ @end smallexample
+@@ -5292,6 +5328,7 @@ might be printed in JSON form as:
+ @}
+ @}
+ ],
++ "escape-source": false,
+ "message": "\u2018struct s\u2019 has no member named @dots{}"
+ @}
+ @end smallexample
+@@ -5349,6 +5386,10 @@ For example, the intraprocedural example
+ ]
+ @end smallexample
+
++Diagnostics have a boolean attribute @code{escape-source}, hinting whether
++non-ASCII bytes should be escaped when printing the pertinent lines of
++source code (@code{true} for diagnostics involving source encoding issues).
++
+ @end table
+
+ @node Warning Options
+diff --git a/gcc/input.c b/gcc/input.c
+--- a/gcc/input.c 2021-07-27 23:55:07.328287915 -0700
++++ b/gcc/input.c 2021-12-14 01:16:01.553943061 -0800
+@@ -913,7 +913,8 @@ make_location (location_t caret, source_
+ source line in order to calculate the display width. If that cannot be done
+ for any reason, then returns the byte column as a fallback. */
+ int
+-location_compute_display_column (expanded_location exploc, int tabstop)
++location_compute_display_column (expanded_location exploc,
++ const cpp_char_column_policy &policy)
+ {
+ if (!(exploc.file && *exploc.file && exploc.line && exploc.column))
+ return exploc.column;
+@@ -921,7 +922,7 @@ location_compute_display_column (expande
+ /* If line is NULL, this function returns exploc.column which is the
+ desired fallback. */
+ return cpp_byte_column_to_display_column (line.get_buffer (), line.length (),
+- exploc.column, tabstop);
++ exploc.column, policy);
+ }
+
+ /* Dump statistics to stderr about the memory usage of the line_table
+@@ -3611,43 +3612,50 @@ test_line_offset_overflow ()
+ void test_cpp_utf8 ()
+ {
+ const int def_tabstop = 8;
++ cpp_char_column_policy policy (def_tabstop, cpp_wcwidth);
++
+ /* Verify that wcwidth of invalid UTF-8 or control bytes is 1. */
+ {
+- int w_bad = cpp_display_width ("\xf0!\x9f!\x98!\x82!", 8, def_tabstop);
++ int w_bad = cpp_display_width ("\xf0!\x9f!\x98!\x82!", 8, policy);
+ ASSERT_EQ (8, w_bad);
+- int w_ctrl = cpp_display_width ("\r\n\v\0\1", 5, def_tabstop);
++ int w_ctrl = cpp_display_width ("\r\n\v\0\1", 5, policy);
+ ASSERT_EQ (5, w_ctrl);
+ }
+
+ /* Verify that wcwidth of valid UTF-8 is as expected. */
+ {
+- const int w_pi = cpp_display_width ("\xcf\x80", 2, def_tabstop);
++ const int w_pi = cpp_display_width ("\xcf\x80", 2, policy);
+ ASSERT_EQ (1, w_pi);
+- const int w_emoji = cpp_display_width ("\xf0\x9f\x98\x82", 4, def_tabstop);
++ const int w_emoji = cpp_display_width ("\xf0\x9f\x98\x82", 4, policy);
+ ASSERT_EQ (2, w_emoji);
+ const int w_umlaut_precomposed = cpp_display_width ("\xc3\xbf", 2,
+- def_tabstop);
++ policy);
+ ASSERT_EQ (1, w_umlaut_precomposed);
+ const int w_umlaut_combining = cpp_display_width ("y\xcc\x88", 3,
+- def_tabstop);
++ policy);
+ ASSERT_EQ (1, w_umlaut_combining);
+- const int w_han = cpp_display_width ("\xe4\xb8\xba", 3, def_tabstop);
++ const int w_han = cpp_display_width ("\xe4\xb8\xba", 3, policy);
+ ASSERT_EQ (2, w_han);
+- const int w_ascii = cpp_display_width ("GCC", 3, def_tabstop);
++ const int w_ascii = cpp_display_width ("GCC", 3, policy);
+ ASSERT_EQ (3, w_ascii);
+ const int w_mixed = cpp_display_width ("\xcf\x80 = 3.14 \xf0\x9f\x98\x82"
+ "\x9f! \xe4\xb8\xba y\xcc\x88",
+- 24, def_tabstop);
++ 24, policy);
+ ASSERT_EQ (18, w_mixed);
+ }
+
+ /* Verify that display width properly expands tabs. */
+ {
+ const char *tstr = "\tabc\td";
+- ASSERT_EQ (6, cpp_display_width (tstr, 6, 1));
+- ASSERT_EQ (10, cpp_display_width (tstr, 6, 3));
+- ASSERT_EQ (17, cpp_display_width (tstr, 6, 8));
+- ASSERT_EQ (1, cpp_display_column_to_byte_column (tstr, 6, 7, 8));
++ ASSERT_EQ (6, cpp_display_width (tstr, 6,
++ cpp_char_column_policy (1, cpp_wcwidth)));
++ ASSERT_EQ (10, cpp_display_width (tstr, 6,
++ cpp_char_column_policy (3, cpp_wcwidth)));
++ ASSERT_EQ (17, cpp_display_width (tstr, 6,
++ cpp_char_column_policy (8, cpp_wcwidth)));
++ ASSERT_EQ (1,
++ cpp_display_column_to_byte_column
++ (tstr, 6, 7, cpp_char_column_policy (8, cpp_wcwidth)));
+ }
+
+ /* Verify that cpp_byte_column_to_display_column can go past the end,
+@@ -3660,13 +3668,13 @@ void test_cpp_utf8 ()
+ /* 111122223456
+ Byte columns. */
+
+- ASSERT_EQ (5, cpp_display_width (str, 6, def_tabstop));
++ ASSERT_EQ (5, cpp_display_width (str, 6, policy));
+ ASSERT_EQ (105,
+- cpp_byte_column_to_display_column (str, 6, 106, def_tabstop));
++ cpp_byte_column_to_display_column (str, 6, 106, policy));
+ ASSERT_EQ (10000,
+- cpp_byte_column_to_display_column (NULL, 0, 10000, def_tabstop));
++ cpp_byte_column_to_display_column (NULL, 0, 10000, policy));
+ ASSERT_EQ (0,
+- cpp_byte_column_to_display_column (NULL, 10000, 0, def_tabstop));
++ cpp_byte_column_to_display_column (NULL, 10000, 0, policy));
+ }
+
+ /* Verify that cpp_display_column_to_byte_column can go past the end,
+@@ -3680,25 +3688,25 @@ void test_cpp_utf8 ()
+ /* 000000000000000000000000000000000111111
+ 111122223333444456666777788889999012345
+ Byte columns. */
+- ASSERT_EQ (4, cpp_display_column_to_byte_column (str, 15, 2, def_tabstop));
++ ASSERT_EQ (4, cpp_display_column_to_byte_column (str, 15, 2, policy));
+ ASSERT_EQ (15,
+- cpp_display_column_to_byte_column (str, 15, 11, def_tabstop));
++ cpp_display_column_to_byte_column (str, 15, 11, policy));
+ ASSERT_EQ (115,
+- cpp_display_column_to_byte_column (str, 15, 111, def_tabstop));
++ cpp_display_column_to_byte_column (str, 15, 111, policy));
+ ASSERT_EQ (10000,
+- cpp_display_column_to_byte_column (NULL, 0, 10000, def_tabstop));
++ cpp_display_column_to_byte_column (NULL, 0, 10000, policy));
+ ASSERT_EQ (0,
+- cpp_display_column_to_byte_column (NULL, 10000, 0, def_tabstop));
++ cpp_display_column_to_byte_column (NULL, 10000, 0, policy));
+
+ /* Verify that we do not interrupt a UTF-8 sequence. */
+- ASSERT_EQ (4, cpp_display_column_to_byte_column (str, 15, 1, def_tabstop));
++ ASSERT_EQ (4, cpp_display_column_to_byte_column (str, 15, 1, policy));
+
+ for (int byte_col = 1; byte_col <= 15; ++byte_col)
+ {
+ const int disp_col
+- = cpp_byte_column_to_display_column (str, 15, byte_col, def_tabstop);
++ = cpp_byte_column_to_display_column (str, 15, byte_col, policy);
+ const int byte_col2
+- = cpp_display_column_to_byte_column (str, 15, disp_col, def_tabstop);
++ = cpp_display_column_to_byte_column (str, 15, disp_col, policy);
+
+ /* If we ask for the display column in the middle of a UTF-8
+ sequence, it will return the length of the partial sequence,
+diff --git a/gcc/input.h b/gcc/input.h
+--- a/gcc/input.h 2021-07-27 23:55:07.328287915 -0700
++++ b/gcc/input.h 2021-12-14 01:16:01.553943061 -0800
+@@ -39,8 +39,11 @@ STATIC_ASSERT (BUILTINS_LOCATION < RESER
+ extern bool is_location_from_builtin_token (location_t);
+ extern expanded_location expand_location (location_t);
+
+-extern int location_compute_display_column (expanded_location exploc,
+- int tabstop);
++class cpp_char_column_policy;
++
++extern int
++location_compute_display_column (expanded_location exploc,
++ const cpp_char_column_policy &policy);
+
+ /* A class capturing the bounds of a buffer, to allow for run-time
+ bounds-checking in a checked build. */
+diff --git a/gcc/opts.c b/gcc/opts.c
+--- a/gcc/opts.c 2021-07-27 23:55:07.364288417 -0700
++++ b/gcc/opts.c 2021-12-14 01:16:01.553943061 -0800
+@@ -2573,6 +2573,10 @@ common_handle_option (struct gcc_options
+ dc->column_origin = value;
+ break;
+
++ case OPT_fdiagnostics_escape_format_:
++ dc->escape_format = (enum diagnostics_escape_format)value;
++ break;
++
+ case OPT_fdiagnostics_show_cwe:
+ dc->show_cwe = value;
+ break;
+diff --git a/gcc/selftest.c b/gcc/selftest.c
+--- a/gcc/selftest.c 2021-07-27 23:55:07.500290315 -0700
++++ b/gcc/selftest.c 2021-12-14 01:16:01.557942991 -0800
+@@ -193,6 +193,21 @@ temp_source_file::temp_source_file (cons
+ fclose (out);
+ }
+
++/* As above, but with a size, to allow for NUL bytes in CONTENT. */
++
++temp_source_file::temp_source_file (const location &loc,
++ const char *suffix,
++ const char *content,
++ size_t sz)
++: named_temp_file (suffix)
++{
++ FILE *out = fopen (get_filename (), "w");
++ if (!out)
++ fail_formatted (loc, "unable to open tempfile: %s", get_filename ());
++ fwrite (content, sz, 1, out);
++ fclose (out);
++}
++
+ /* Avoid introducing locale-specific differences in the results
+ by hardcoding open_quote and close_quote. */
+
+diff --git a/gcc/selftest.h b/gcc/selftest.h
+--- a/gcc/selftest.h 2021-07-27 23:55:07.500290315 -0700
++++ b/gcc/selftest.h 2021-12-14 01:16:01.557942991 -0800
+@@ -112,6 +112,8 @@ class temp_source_file : public named_te
+ public:
+ temp_source_file (const location &loc, const char *suffix,
+ const char *content);
++ temp_source_file (const location &loc, const char *suffix,
++ const char *content, size_t sz);
+ };
+
+ /* RAII-style class for avoiding introducing locale-specific differences
+diff --git a/gcc/testsuite/c-c++-common/diagnostic-format-json-1.c b/gcc/testsuite/c-c++-common/diagnostic-format-json-1.c
+--- a/gcc/testsuite/c-c++-common/diagnostic-format-json-1.c 2021-07-27 23:55:07.596291654 -0700
++++ b/gcc/testsuite/c-c++-common/diagnostic-format-json-1.c 2021-12-14 01:16:01.557942991 -0800
+@@ -9,6 +9,7 @@
+
+ /* { dg-regexp "\"kind\": \"error\"" } */
+ /* { dg-regexp "\"column-origin\": 1" } */
++/* { dg-regexp "\"escape-source\": false" } */
+ /* { dg-regexp "\"message\": \"#error message\"" } */
+
+ /* { dg-regexp "\"caret\": \{" } */
+diff --git a/gcc/testsuite/c-c++-common/diagnostic-format-json-2.c b/gcc/testsuite/c-c++-common/diagnostic-format-json-2.c
+--- a/gcc/testsuite/c-c++-common/diagnostic-format-json-2.c 2021-07-27 23:55:07.596291654 -0700
++++ b/gcc/testsuite/c-c++-common/diagnostic-format-json-2.c 2021-12-14 01:16:01.557942991 -0800
+@@ -9,6 +9,7 @@
+
+ /* { dg-regexp "\"kind\": \"warning\"" } */
+ /* { dg-regexp "\"column-origin\": 1" } */
++/* { dg-regexp "\"escape-source\": false" } */
+ /* { dg-regexp "\"message\": \"#warning message\"" } */
+ /* { dg-regexp "\"option\": \"-Wcpp\"" } */
+ /* { dg-regexp "\"option_url\": \"https:\[^\n\r\"\]*#index-Wcpp\"" } */
+diff --git a/gcc/testsuite/c-c++-common/diagnostic-format-json-3.c b/gcc/testsuite/c-c++-common/diagnostic-format-json-3.c
+--- a/gcc/testsuite/c-c++-common/diagnostic-format-json-3.c 2021-07-27 23:55:07.596291654 -0700
++++ b/gcc/testsuite/c-c++-common/diagnostic-format-json-3.c 2021-12-14 01:16:01.557942991 -0800
+@@ -9,6 +9,7 @@
+
+ /* { dg-regexp "\"kind\": \"error\"" } */
+ /* { dg-regexp "\"column-origin\": 1" } */
++/* { dg-regexp "\"escape-source\": false" } */
+ /* { dg-regexp "\"message\": \"#warning message\"" } */
+ /* { dg-regexp "\"option\": \"-Werror=cpp\"" } */
+ /* { dg-regexp "\"option_url\": \"https:\[^\n\r\"\]*#index-Wcpp\"" } */
+diff --git a/gcc/testsuite/c-c++-common/diagnostic-format-json-4.c b/gcc/testsuite/c-c++-common/diagnostic-format-json-4.c
+--- a/gcc/testsuite/c-c++-common/diagnostic-format-json-4.c 2021-07-27 23:55:07.596291654 -0700
++++ b/gcc/testsuite/c-c++-common/diagnostic-format-json-4.c 2021-12-14 01:16:01.557942991 -0800
+@@ -19,6 +19,7 @@ int test (void)
+
+ /* { dg-regexp "\"kind\": \"note\"" } */
+ /* { dg-regexp "\"message\": \"...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'\"" } */
++/* { dg-regexp "\"escape-source\": false" } */
+
+ /* { dg-regexp "\"caret\": \{" } */
+ /* { dg-regexp "\"file\": \"\[^\n\r\"\]*diagnostic-format-json-4.c\"" } */
+@@ -39,6 +40,7 @@ int test (void)
+ /* { dg-regexp "\"kind\": \"warning\"" } */
+ /* { dg-regexp "\"column-origin\": 1" } */
+ /* { dg-regexp "\"message\": \"this 'if' clause does not guard...\"" } */
++/* { dg-regexp "\"escape-source\": false" } */
+ /* { dg-regexp "\"option\": \"-Wmisleading-indentation\"" } */
+ /* { dg-regexp "\"option_url\": \"https:\[^\n\r\"\]*#index-Wmisleading-indentation\"" } */
+
+diff --git a/gcc/testsuite/c-c++-common/diagnostic-format-json-5.c b/gcc/testsuite/c-c++-common/diagnostic-format-json-5.c
+--- a/gcc/testsuite/c-c++-common/diagnostic-format-json-5.c 2021-07-27 23:55:07.596291654 -0700
++++ b/gcc/testsuite/c-c++-common/diagnostic-format-json-5.c 2021-12-14 01:16:01.557942991 -0800
+@@ -14,6 +14,7 @@ int test (struct s *ptr)
+
+ /* { dg-regexp "\"kind\": \"error\"" } */
+ /* { dg-regexp "\"column-origin\": 1" } */
++/* { dg-regexp "\"escape-source\": false" } */
+ /* { dg-regexp "\"message\": \".*\"" } */
+
+ /* Verify fix-it hints. */
+diff --git a/gcc/testsuite/gcc.dg/cpp/warn-normalized-4-bytes.c b/gcc/testsuite/gcc.dg/cpp/warn-normalized-4-bytes.c
+--- a/gcc/testsuite/gcc.dg/cpp/warn-normalized-4-bytes.c 1969-12-31 16:00:00.000000000 -0800
++++ b/gcc/testsuite/gcc.dg/cpp/warn-normalized-4-bytes.c 2021-12-14 01:16:01.557942991 -0800
+@@ -0,0 +1,21 @@
++// { dg-do preprocess }
++// { dg-options "-std=gnu99 -Werror=normalized=nfc -fdiagnostics-show-caret -fdiagnostics-escape-format=bytes" }
++/* { dg-message "some warnings being treated as errors" "" {target "*-*-*"} 0 } */
++
++/* འ= U+0F43 TIBETAN LETTER GHA, which has decomposition "0F42 0FB7" i.e.
++ U+0F42 TIBETAN LETTER GA: à½
++ U+0FB7 TIBETAN SUBJOINED LETTER HA: ྷ
++
++ The UTF-8 encoding of U+0F43 TIBETAN LETTER GHA is: E0 BD 83. */
++
++foo before_\u0F43_after bar // { dg-error "`before_.U00000f43_after' is not in NFC .-Werror=normalized=." }
++/* { dg-begin-multiline-output "" }
++ foo before_\u0F43_after bar
++ ^~~~~~~~~~~~~~~~~~~
++ { dg-end-multiline-output "" } */
++
++foo before_à½_after bar // { dg-error "`before_.U00000f43_after' is not in NFC .-Werror=normalized=." }
++/* { dg-begin-multiline-output "" }
++ foo before_<e0><bd><83>_after bar
++ ^~~~~~~~~~~~~~~~~~~~~~~~~
++ { dg-end-multiline-output "" } */
+diff --git a/gcc/testsuite/gcc.dg/cpp/warn-normalized-4-unicode.c b/gcc/testsuite/gcc.dg/cpp/warn-normalized-4-unicode.c
+--- a/gcc/testsuite/gcc.dg/cpp/warn-normalized-4-unicode.c 1969-12-31 16:00:00.000000000 -0800
++++ b/gcc/testsuite/gcc.dg/cpp/warn-normalized-4-unicode.c 2021-12-14 01:16:01.557942991 -0800
+@@ -0,0 +1,19 @@
++// { dg-do preprocess }
++// { dg-options "-std=gnu99 -Werror=normalized=nfc -fdiagnostics-show-caret -fdiagnostics-escape-format=unicode" }
++/* { dg-message "some warnings being treated as errors" "" {target "*-*-*"} 0 } */
++
++/* འ= U+0F43 TIBETAN LETTER GHA, which has decomposition "0F42 0FB7" i.e.
++ U+0F42 TIBETAN LETTER GA: à½
++ U+0FB7 TIBETAN SUBJOINED LETTER HA: ྷ */
++
++foo before_\u0F43_after bar // { dg-error "`before_.U00000f43_after' is not in NFC .-Werror=normalized=." }
++/* { dg-begin-multiline-output "" }
++ foo before_\u0F43_after bar
++ ^~~~~~~~~~~~~~~~~~~
++ { dg-end-multiline-output "" } */
++
++foo before_à½_after bar // { dg-error "`before_.U00000f43_after' is not in NFC .-Werror=normalized=." }
++/* { dg-begin-multiline-output "" }
++ foo before_<U+0F43>_after bar
++ ^~~~~~~~~~~~~~~~~~~~~
++ { dg-end-multiline-output "" } */
+diff --git a/gcc/testsuite/gfortran.dg/diagnostic-format-json-1.F90 b/gcc/testsuite/gfortran.dg/diagnostic-format-json-1.F90
+--- a/gcc/testsuite/gfortran.dg/diagnostic-format-json-1.F90 2021-07-27 23:55:08.472303878 -0700
++++ b/gcc/testsuite/gfortran.dg/diagnostic-format-json-1.F90 2021-12-14 01:16:01.557942991 -0800
+@@ -9,6 +9,7 @@
+
+ ! { dg-regexp "\"kind\": \"error\"" }
+ ! { dg-regexp "\"column-origin\": 1" }
++! { dg-regexp "\"escape-source\": false" }
+ ! { dg-regexp "\"message\": \"#error message\"" }
+
+ ! { dg-regexp "\"caret\": \{" }
+diff --git a/gcc/testsuite/gfortran.dg/diagnostic-format-json-2.F90 b/gcc/testsuite/gfortran.dg/diagnostic-format-json-2.F90
+--- a/gcc/testsuite/gfortran.dg/diagnostic-format-json-2.F90 2021-07-27 23:55:08.472303878 -0700
++++ b/gcc/testsuite/gfortran.dg/diagnostic-format-json-2.F90 2021-12-14 01:16:01.557942991 -0800
+@@ -9,6 +9,7 @@
+
+ ! { dg-regexp "\"kind\": \"warning\"" }
+ ! { dg-regexp "\"column-origin\": 1" }
++! { dg-regexp "\"escape-source\": false" }
+ ! { dg-regexp "\"message\": \"#warning message\"" }
+ ! { dg-regexp "\"option\": \"-Wcpp\"" }
+ ! { dg-regexp "\"option_url\": \"\[^\n\r\"\]*#index-Wcpp\"" }
+diff --git a/gcc/testsuite/gfortran.dg/diagnostic-format-json-3.F90 b/gcc/testsuite/gfortran.dg/diagnostic-format-json-3.F90
+--- a/gcc/testsuite/gfortran.dg/diagnostic-format-json-3.F90 2021-07-27 23:55:08.472303878 -0700
++++ b/gcc/testsuite/gfortran.dg/diagnostic-format-json-3.F90 2021-12-14 01:16:01.557942991 -0800
+@@ -9,6 +9,7 @@
+
+ ! { dg-regexp "\"kind\": \"error\"" }
+ ! { dg-regexp "\"column-origin\": 1" }
++! { dg-regexp "\"escape-source\": false" }
+ ! { dg-regexp "\"message\": \"#warning message\"" }
+ ! { dg-regexp "\"option\": \"-Werror=cpp\"" }
+ ! { dg-regexp "\"option_url\": \"\[^\n\r\"\]*#index-Wcpp\"" }
+diff --git a/libcpp/charset.c b/libcpp/charset.c
+--- a/libcpp/charset.c 2021-07-27 23:55:08.712307227 -0700
++++ b/libcpp/charset.c 2021-12-14 01:16:01.557942991 -0800
+@@ -1552,12 +1552,14 @@ convert_escape (cpp_reader *pfile, const
+ "unknown escape sequence: '\\%c'", (int) c);
+ else
+ {
++ encoding_rich_location rich_loc (pfile);
++
+ /* diagnostic.c does not support "%03o". When it does, this
+ code can use %03o directly in the diagnostic again. */
+ char buf[32];
+ sprintf(buf, "%03o", (int) c);
+- cpp_error (pfile, CPP_DL_PEDWARN,
+- "unknown escape sequence: '\\%s'", buf);
++ cpp_error_at (pfile, CPP_DL_PEDWARN, &rich_loc,
++ "unknown escape sequence: '\\%s'", buf);
+ }
+ }
+
+@@ -2280,14 +2282,16 @@ cpp_string_location_reader::get_next ()
+ }
+
+ cpp_display_width_computation::
+-cpp_display_width_computation (const char *data, int data_length, int tabstop) :
++cpp_display_width_computation (const char *data, int data_length,
++ const cpp_char_column_policy &policy) :
+ m_begin (data),
+ m_next (m_begin),
+ m_bytes_left (data_length),
+- m_tabstop (tabstop),
++ m_policy (policy),
+ m_display_cols (0)
+ {
+- gcc_assert (m_tabstop > 0);
++ gcc_assert (policy.m_tabstop > 0);
++ gcc_assert (policy.m_width_cb);
+ }
+
+
+@@ -2299,19 +2303,28 @@ cpp_display_width_computation (const cha
+ point to a valid UTF-8-encoded sequence, then it will be treated as a single
+ byte with display width 1. m_cur_display_col is the current display column,
+ relative to which tab stops should be expanded. Returns the display width of
+- the codepoint just processed. */
++ the codepoint just processed.
++ If OUT is non-NULL, it is populated. */
+
+ int
+-cpp_display_width_computation::process_next_codepoint ()
++cpp_display_width_computation::process_next_codepoint (cpp_decoded_char *out)
+ {
+ cppchar_t c;
+ int next_width;
+
++ if (out)
++ out->m_start_byte = m_next;
++
+ if (*m_next == '\t')
+ {
+ ++m_next;
+ --m_bytes_left;
+- next_width = m_tabstop - (m_display_cols % m_tabstop);
++ next_width = m_policy.m_tabstop - (m_display_cols % m_policy.m_tabstop);
++ if (out)
++ {
++ out->m_ch = '\t';
++ out->m_valid_ch = true;
++ }
+ }
+ else if (one_utf8_to_cppchar ((const uchar **) &m_next, &m_bytes_left, &c)
+ != 0)
+@@ -2321,14 +2334,24 @@ cpp_display_width_computation::process_n
+ of one. */
+ ++m_next;
+ --m_bytes_left;
+- next_width = 1;
++ next_width = m_policy.m_undecoded_byte_width;
++ if (out)
++ out->m_valid_ch = false;
+ }
+ else
+ {
+ /* one_utf8_to_cppchar() has updated m_next and m_bytes_left for us. */
+- next_width = cpp_wcwidth (c);
++ next_width = m_policy.m_width_cb (c);
++ if (out)
++ {
++ out->m_ch = c;
++ out->m_valid_ch = true;
++ }
+ }
+
++ if (out)
++ out->m_next_byte = m_next;
++
+ m_display_cols += next_width;
+ return next_width;
+ }
+@@ -2344,7 +2367,7 @@ cpp_display_width_computation::advance_d
+ const int start = m_display_cols;
+ const int target = start + n;
+ while (m_display_cols < target && !done ())
+- process_next_codepoint ();
++ process_next_codepoint (NULL);
+ return m_display_cols - start;
+ }
+
+@@ -2352,29 +2375,33 @@ cpp_display_width_computation::advance_d
+ how many display columns are occupied by the first COLUMN bytes. COLUMN
+ may exceed DATA_LENGTH, in which case the phantom bytes at the end are
+ treated as if they have display width 1. Tabs are expanded to the next tab
+- stop, relative to the start of DATA. */
++ stop, relative to the start of DATA, and non-printable-ASCII characters
++ will be escaped as per POLICY. */
+
+ int
+ cpp_byte_column_to_display_column (const char *data, int data_length,
+- int column, int tabstop)
++ int column,
++ const cpp_char_column_policy &policy)
+ {
+ const int offset = MAX (0, column - data_length);
+- cpp_display_width_computation dw (data, column - offset, tabstop);
++ cpp_display_width_computation dw (data, column - offset, policy);
+ while (!dw.done ())
+- dw.process_next_codepoint ();
++ dw.process_next_codepoint (NULL);
+ return dw.display_cols_processed () + offset;
+ }
+
+ /* For the string of length DATA_LENGTH bytes that begins at DATA, compute
+ the least number of bytes that will result in at least DISPLAY_COL display
+ columns. The return value may exceed DATA_LENGTH if the entire string does
+- not occupy enough display columns. */
++ not occupy enough display columns. Non-printable-ASCII characters
++ will be escaped as per POLICY. */
+
+ int
+ cpp_display_column_to_byte_column (const char *data, int data_length,
+- int display_col, int tabstop)
++ int display_col,
++ const cpp_char_column_policy &policy)
+ {
+- cpp_display_width_computation dw (data, data_length, tabstop);
++ cpp_display_width_computation dw (data, data_length, policy);
+ const int avail_display = dw.advance_display_cols (display_col);
+ return dw.bytes_processed () + MAX (0, display_col - avail_display);
+ }
+diff --git a/libcpp/errors.c b/libcpp/errors.c
+--- a/libcpp/errors.c 2021-07-27 23:55:08.712307227 -0700
++++ b/libcpp/errors.c 2021-12-14 01:16:01.557942991 -0800
+@@ -27,6 +27,31 @@ along with this program; see the file CO
+ #include "cpplib.h"
+ #include "internal.h"
+
++/* Get a location_t for the current location in PFILE,
++ generally that of the previously lexed token. */
++
++location_t
++cpp_diagnostic_get_current_location (cpp_reader *pfile)
++{
++ if (CPP_OPTION (pfile, traditional))
++ {
++ if (pfile->state.in_directive)
++ return pfile->directive_line;
++ else
++ return pfile->line_table->highest_line;
++ }
++ /* We don't want to refer to a token before the beginning of the
++ current run -- that is invalid. */
++ else if (pfile->cur_token == pfile->cur_run->base)
++ {
++ return 0;
++ }
++ else
++ {
++ return pfile->cur_token[-1].src_loc;
++ }
++}
++
+ /* Print a diagnostic at the given location. */
+
+ ATTRIBUTE_FPTR_PRINTF(5,0)
+@@ -52,25 +77,7 @@ cpp_diagnostic (cpp_reader * pfile, enum
+ enum cpp_warning_reason reason,
+ const char *msgid, va_list *ap)
+ {
+- location_t src_loc;
+-
+- if (CPP_OPTION (pfile, traditional))
+- {
+- if (pfile->state.in_directive)
+- src_loc = pfile->directive_line;
+- else
+- src_loc = pfile->line_table->highest_line;
+- }
+- /* We don't want to refer to a token before the beginning of the
+- current run -- that is invalid. */
+- else if (pfile->cur_token == pfile->cur_run->base)
+- {
+- src_loc = 0;
+- }
+- else
+- {
+- src_loc = pfile->cur_token[-1].src_loc;
+- }
++ location_t src_loc = cpp_diagnostic_get_current_location (pfile);
+ rich_location richloc (pfile->line_table, src_loc);
+ return cpp_diagnostic_at (pfile, level, reason, &richloc, msgid, ap);
+ }
+@@ -142,6 +149,43 @@ cpp_warning_syshdr (cpp_reader * pfile,
+
+ va_end (ap);
+ return ret;
++}
++
++/* As cpp_warning above, but use RICHLOC as the location of the diagnostic. */
++
++bool cpp_warning_at (cpp_reader *pfile, enum cpp_warning_reason reason,
++ rich_location *richloc, const char *msgid, ...)
++{
++ va_list ap;
++ bool ret;
++
++ va_start (ap, msgid);
++
++ ret = cpp_diagnostic_at (pfile, CPP_DL_WARNING, reason, richloc,
++ msgid, &ap);
++
++ va_end (ap);
++ return ret;
++
++}
++
++/* As cpp_pedwarning above, but use RICHLOC as the location of the
++ diagnostic. */
++
++bool
++cpp_pedwarning_at (cpp_reader * pfile, enum cpp_warning_reason reason,
++ rich_location *richloc, const char *msgid, ...)
++{
++ va_list ap;
++ bool ret;
++
++ va_start (ap, msgid);
++
++ ret = cpp_diagnostic_at (pfile, CPP_DL_PEDWARN, reason, richloc,
++ msgid, &ap);
++
++ va_end (ap);
++ return ret;
+ }
+
+ /* Print a diagnostic at a specific location. */
+diff --git a/libcpp/include/cpplib.h b/libcpp/include/cpplib.h
+--- a/libcpp/include/cpplib.h 2021-12-13 23:23:05.768437079 -0800
++++ b/libcpp/include/cpplib.h 2021-12-14 01:20:16.189507386 -0800
+@@ -1275,6 +1275,14 @@ extern bool cpp_warning_syshdr (cpp_read
+ const char *msgid, ...)
+ ATTRIBUTE_PRINTF_3;
+
++/* As their counterparts above, but use RICHLOC. */
++extern bool cpp_warning_at (cpp_reader *, enum cpp_warning_reason,
++ rich_location *richloc, const char *msgid, ...)
++ ATTRIBUTE_PRINTF_4;
++extern bool cpp_pedwarning_at (cpp_reader *, enum cpp_warning_reason,
++ rich_location *richloc, const char *msgid, ...)
++ ATTRIBUTE_PRINTF_4;
++
+ /* Output a diagnostic with "MSGID: " preceding the
+ error string of errno. No location is printed. */
+ extern bool cpp_errno (cpp_reader *, enum cpp_diagnostic_level,
+@@ -1435,42 +1443,95 @@ extern const char * cpp_get_userdef_suff
+
+ /* In charset.c */
+
++/* The result of attempting to decode a run of UTF-8 bytes. */
++
++struct cpp_decoded_char
++{
++ const char *m_start_byte;
++ const char *m_next_byte;
++
++ bool m_valid_ch;
++ cppchar_t m_ch;
++};
++
++/* Information for mapping between code points and display columns.
++
++ This is a tabstop value, along with a callback for getting the
++ widths of characters. Normally this callback is cpp_wcwidth, but we
++ support other schemes for escaping non-ASCII unicode as a series of
++ ASCII chars when printing the user's source code in diagnostic-show-locus.c
++
++ For example, consider:
++ - the Unicode character U+03C0 "GREEK SMALL LETTER PI" (UTF-8: 0xCF 0x80)
++ - the Unicode character U+1F642 "SLIGHTLY SMILING FACE"
++ (UTF-8: 0xF0 0x9F 0x99 0x82)
++ - the byte 0xBF (a stray trailing byte of a UTF-8 character)
++ Normally U+03C0 would occupy one display column, U+1F642
++ would occupy two display columns, and the stray byte would be
++ printed verbatim as one display column.
++
++ However when escaping them as unicode code points as "<U+03C0>"
++ and "<U+1F642>" they occupy 8 and 9 display columns respectively,
++ and when escaping them as bytes as "<CF><80>" and "<F0><9F><99><82>"
++ they occupy 8 and 16 display columns respectively. In both cases
++ the stray byte is escaped to <BF> as 4 display columns. */
++
++struct cpp_char_column_policy
++{
++ cpp_char_column_policy (int tabstop,
++ int (*width_cb) (cppchar_t c))
++ : m_tabstop (tabstop),
++ m_undecoded_byte_width (1),
++ m_width_cb (width_cb)
++ {}
++
++ int m_tabstop;
++ /* Width in display columns of a stray byte that isn't decodable
++ as UTF-8. */
++ int m_undecoded_byte_width;
++ int (*m_width_cb) (cppchar_t c);
++};
++
+ /* A class to manage the state while converting a UTF-8 sequence to cppchar_t
+ and computing the display width one character at a time. */
+ class cpp_display_width_computation {
+ public:
+ cpp_display_width_computation (const char *data, int data_length,
+- int tabstop);
++ const cpp_char_column_policy &policy);
+ const char *next_byte () const { return m_next; }
+ int bytes_processed () const { return m_next - m_begin; }
+ int bytes_left () const { return m_bytes_left; }
+ bool done () const { return !bytes_left (); }
+ int display_cols_processed () const { return m_display_cols; }
+
+- int process_next_codepoint ();
++ int process_next_codepoint (cpp_decoded_char *out);
+ int advance_display_cols (int n);
+
+ private:
+ const char *const m_begin;
+ const char *m_next;
+ size_t m_bytes_left;
+- const int m_tabstop;
++ const cpp_char_column_policy &m_policy;
+ int m_display_cols;
+ };
+
+ /* Convenience functions that are simple use cases for class
+ cpp_display_width_computation. Tab characters will be expanded to spaces
+- as determined by TABSTOP. */
++ as determined by POLICY.m_tabstop, and non-printable-ASCII characters
++ will be escaped as per POLICY. */
++
+ int cpp_byte_column_to_display_column (const char *data, int data_length,
+- int column, int tabstop);
++ int column,
++ const cpp_char_column_policy &policy);
+ inline int cpp_display_width (const char *data, int data_length,
+- int tabstop)
++ const cpp_char_column_policy &policy)
+ {
+ return cpp_byte_column_to_display_column (data, data_length, data_length,
+- tabstop);
++ policy);
+ }
+ int cpp_display_column_to_byte_column (const char *data, int data_length,
+- int display_col, int tabstop);
++ int display_col,
++ const cpp_char_column_policy &policy);
+ int cpp_wcwidth (cppchar_t c);
+
+ #endif /* ! LIBCPP_CPPLIB_H */
+diff --git a/libcpp/include/line-map.h b/libcpp/include/line-map.h
+--- a/libcpp/include/line-map.h 2021-07-27 23:55:08.716307283 -0700
++++ b/libcpp/include/line-map.h 2021-12-14 01:16:01.557942991 -0800
+@@ -1781,6 +1781,18 @@ class rich_location
+ const diagnostic_path *get_path () const { return m_path; }
+ void set_path (const diagnostic_path *path) { m_path = path; }
+
++ /* A flag for hinting that the diagnostic involves character encoding
++ issues, and thus that it will be helpful to the user if we show some
++ representation of how the characters in the pertinent source lines
++ are encoded.
++ The default is false (i.e. do not escape).
++ When set to true, non-ASCII bytes in the pertinent source lines will
++ be escaped in a manner controlled by the user-supplied option
++ -fdiagnostics-escape-format=, so that the user can better understand
++ what's going on with the encoding in their source file. */
++ bool escape_on_output_p () const { return m_escape_on_output; }
++ void set_escape_on_output (bool flag) { m_escape_on_output = flag; }
++
+ private:
+ bool reject_impossible_fixit (location_t where);
+ void stop_supporting_fixits ();
+@@ -1807,6 +1819,7 @@ protected:
+ bool m_fixits_cannot_be_auto_applied;
+
+ const diagnostic_path *m_path;
++ bool m_escape_on_output;
+ };
+
+ /* A struct for the result of range_label::get_text: a NUL-terminated buffer
+diff --git a/libcpp/internal.h b/libcpp/internal.h
+--- a/libcpp/internal.h 2021-12-13 23:23:05.768437079 -0800
++++ b/libcpp/internal.h 2021-12-14 01:16:01.557942991 -0800
+@@ -776,6 +776,9 @@ extern void _cpp_do_file_change (cpp_rea
+ extern void _cpp_pop_buffer (cpp_reader *);
+ extern char *_cpp_bracket_include (cpp_reader *);
+
++/* In errors.c */
++extern location_t cpp_diagnostic_get_current_location (cpp_reader *);
++
+ /* In traditional.c. */
+ extern bool _cpp_scan_out_logical_line (cpp_reader *, cpp_macro *, bool);
+ extern bool _cpp_read_logical_line_trad (cpp_reader *);
+@@ -942,6 +945,26 @@ int linemap_get_expansion_line (class li
+ const char* linemap_get_expansion_filename (class line_maps *,
+ location_t);
+
++/* A subclass of rich_location for emitting a diagnostic
++ at the current location of the reader, but flagging
++ it with set_escape_on_output (true). */
++class encoding_rich_location : public rich_location
++{
++ public:
++ encoding_rich_location (cpp_reader *pfile)
++ : rich_location (pfile->line_table,
++ cpp_diagnostic_get_current_location (pfile))
++ {
++ set_escape_on_output (true);
++ }
++
++ encoding_rich_location (cpp_reader *pfile, location_t loc)
++ : rich_location (pfile->line_table, loc)
++ {
++ set_escape_on_output (true);
++ }
++};
++
+ #ifdef __cplusplus
+ }
+ #endif
+diff --git a/libcpp/lex.c b/libcpp/lex.c
+--- a/libcpp/lex.c 2021-12-14 01:14:48.435225968 -0800
++++ b/libcpp/lex.c 2021-12-14 01:24:37.220995816 -0800
+@@ -1774,7 +1774,11 @@ skip_whitespace (cpp_reader *pfile, cppc
+ while (is_nvspace (c));
+
+ if (saw_NUL)
+- cpp_error (pfile, CPP_DL_WARNING, "null character(s) ignored");
++ {
++ encoding_rich_location rich_loc (pfile);
++ cpp_error_at (pfile, CPP_DL_WARNING, &rich_loc,
++ "null character(s) ignored");
++ }
+
+ buffer->cur--;
+ }
+@@ -1803,6 +1807,28 @@ warn_about_normalization (cpp_reader *pf
+ if (CPP_OPTION (pfile, warn_normalize) < NORMALIZE_STATE_RESULT (s)
+ && !pfile->state.skipping)
+ {
++ location_t loc = token->src_loc;
++
++ /* If possible, create a location range for the token. */
++ if (loc >= RESERVED_LOCATION_COUNT
++ && token->type != CPP_EOF
++ /* There must be no line notes to process. */
++ && (!(pfile->buffer->cur
++ >= pfile->buffer->notes[pfile->buffer->cur_note].pos
++ && !pfile->overlaid_buffer)))
++ {
++ source_range tok_range;
++ tok_range.m_start = loc;
++ tok_range.m_finish
++ = linemap_position_for_column (pfile->line_table,
++ CPP_BUF_COLUMN (pfile->buffer,
++ pfile->buffer->cur));
++ loc = COMBINE_LOCATION_DATA (pfile->line_table,
++ loc, tok_range, NULL);
++ }
++
++ encoding_rich_location rich_loc (pfile, loc);
++
+ /* Make sure that the token is printed using UCNs, even
+ if we'd otherwise happily print UTF-8. */
+ unsigned char *buf = XNEWVEC (unsigned char, cpp_token_len (token));
+@@ -1810,11 +1836,11 @@ warn_about_normalization (cpp_reader *pf
+
+ sz = cpp_spell_token (pfile, token, buf, false) - buf;
+ if (NORMALIZE_STATE_RESULT (s) == normalized_C)
+- cpp_warning_with_line (pfile, CPP_W_NORMALIZE, token->src_loc, 0,
+- "`%.*s' is not in NFKC", (int) sz, buf);
++ cpp_warning_at (pfile, CPP_W_NORMALIZE, &rich_loc,
++ "`%.*s' is not in NFKC", (int) sz, buf);
+ else
+- cpp_warning_with_line (pfile, CPP_W_NORMALIZE, token->src_loc, 0,
+- "`%.*s' is not in NFC", (int) sz, buf);
++ cpp_warning_at (pfile, CPP_W_NORMALIZE, &rich_loc,
++ "`%.*s' is not in NFC", (int) sz, buf);
+ free (buf);
+ }
+ }
+diff --git a/libcpp/line-map.c b/libcpp/line-map.c
+--- a/libcpp/line-map.c 2021-07-27 23:55:08.716307283 -0700
++++ b/libcpp/line-map.c 2021-12-14 01:16:01.561942921 -0800
+@@ -2086,7 +2086,8 @@ rich_location::rich_location (line_maps
+ m_fixit_hints (),
+ m_seen_impossible_fixit (false),
+ m_fixits_cannot_be_auto_applied (false),
+- m_path (NULL)
++ m_path (NULL),
++ m_escape_on_output (false)
+ {
+ add_range (loc, SHOW_RANGE_WITH_CARET, label);
+ }
diff --git a/meta/recipes-devtools/gcc/gcc/0002-CVE-2021-42574.patch b/meta/recipes-devtools/gcc/gcc/0002-CVE-2021-42574.patch
new file mode 100644
index 0000000000..9bad81d4d0
--- /dev/null
+++ b/meta/recipes-devtools/gcc/gcc/0002-CVE-2021-42574.patch
@@ -0,0 +1,1765 @@
+From 51c500269bf53749b107807d84271385fad35628 Mon Sep 17 00:00:00 2001
+From: Marek Polacek <polacek@redhat.com>
+Date: Wed, 6 Oct 2021 14:33:59 -0400
+Subject: [PATCH] libcpp: Implement -Wbidi-chars for CVE-2021-42574 [PR103026]
+
+From a link below:
+"An issue was discovered in the Bidirectional Algorithm in the Unicode
+Specification through 14.0. It permits the visual reordering of
+characters via control sequences, which can be used to craft source code
+that renders different logic than the logical ordering of tokens
+ingested by compilers and interpreters. Adversaries can leverage this to
+encode source code for compilers accepting Unicode such that targeted
+vulnerabilities are introduced invisibly to human reviewers."
+
+More info:
+https://nvd.nist.gov/vuln/detail/CVE-2021-42574
+https://trojansource.codes/
+
+This is not a compiler bug. However, to mitigate the problem, this patch
+implements -Wbidi-chars=[none|unpaired|any] to warn about possibly
+misleading Unicode bidirectional control characters the preprocessor may
+encounter.
+
+The default is =unpaired, which warns about improperly terminated
+bidirectional control characters; e.g. a LRE without its corresponding PDF.
+The level =any warns about any use of bidirectional control characters.
+
+This patch handles both UCNs and UTF-8 characters. UCNs designating
+bidi characters in identifiers are accepted since r204886. Then r217144
+enabled -fextended-identifiers by default. Extended characters in C/C++
+identifiers have been accepted since r275979. However, this patch still
+warns about mixing UTF-8 and UCN bidi characters; there seems to be no
+good reason to allow mixing them.
+
+We warn in different contexts: comments (both C and C++-style), string
+literals, character constants, and identifiers. Expectedly, UCNs are ignored
+in comments and raw string literals. The bidirectional control characters
+can nest so this patch handles that as well.
+
+I have not included nor tested this at all with Fortran (which also has
+string literals and line comments).
+
+Dave M. posted patches improving diagnostic involving Unicode characters.
+This patch does not make use of this new infrastructure yet.
+
+ PR preprocessor/103026
+
+gcc/c-family/ChangeLog:
+
+ * c.opt (Wbidi-chars, Wbidi-chars=): New option.
+
+gcc/ChangeLog:
+
+ * doc/invoke.texi: Document -Wbidi-chars.
+
+libcpp/ChangeLog:
+
+ * include/cpplib.h (enum cpp_bidirectional_level): New.
+ (struct cpp_options): Add cpp_warn_bidirectional.
+ (enum cpp_warning_reason): Add CPP_W_BIDIRECTIONAL.
+ * internal.h (struct cpp_reader): Add warn_bidi_p member
+ function.
+ * init.c (cpp_create_reader): Set cpp_warn_bidirectional.
+ * lex.c (bidi): New namespace.
+ (get_bidi_utf8): New function.
+ (get_bidi_ucn): Likewise.
+ (maybe_warn_bidi_on_close): Likewise.
+ (maybe_warn_bidi_on_char): Likewise.
+ (_cpp_skip_block_comment): Implement warning about bidirectional
+ control characters.
+ (skip_line_comment): Likewise.
+ (forms_identifier_p): Likewise.
+ (lex_identifier): Likewise.
+ (lex_string): Likewise.
+ (lex_raw_string): Likewise.
+
+gcc/testsuite/ChangeLog:
+
+ * c-c++-common/Wbidi-chars-1.c: New test.
+ * c-c++-common/Wbidi-chars-2.c: New test.
+ * c-c++-common/Wbidi-chars-3.c: New test.
+ * c-c++-common/Wbidi-chars-4.c: New test.
+ * c-c++-common/Wbidi-chars-5.c: New test.
+ * c-c++-common/Wbidi-chars-6.c: New test.
+ * c-c++-common/Wbidi-chars-7.c: New test.
+ * c-c++-common/Wbidi-chars-8.c: New test.
+ * c-c++-common/Wbidi-chars-9.c: New test.
+ * c-c++-common/Wbidi-chars-10.c: New test.
+ * c-c++-common/Wbidi-chars-11.c: New test.
+ * c-c++-common/Wbidi-chars-12.c: New test.
+ * c-c++-common/Wbidi-chars-13.c: New test.
+ * c-c++-common/Wbidi-chars-14.c: New test.
+ * c-c++-common/Wbidi-chars-15.c: New test.
+ * c-c++-common/Wbidi-chars-16.c: New test.
+ * c-c++-common/Wbidi-chars-17.c: New test.
+
+CVE: CVE-2021-42574
+Upstream-Status: Backport [https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=51c500269bf53749b107807d84271385fad35628]
+Signed-off-by: Pgowda <pgowda.cve@gmail.com>
+
+---
+ gcc/c-family/c.opt | 24 ++
+ gcc/doc/invoke.texi | 21 +-
+ gcc/testsuite/c-c++-common/Wbidi-chars-1.c | 12 +
+ gcc/testsuite/c-c++-common/Wbidi-chars-10.c | 27 ++
+ gcc/testsuite/c-c++-common/Wbidi-chars-11.c | 13 +
+ gcc/testsuite/c-c++-common/Wbidi-chars-12.c | 19 +
+ gcc/testsuite/c-c++-common/Wbidi-chars-13.c | 17 +
+ gcc/testsuite/c-c++-common/Wbidi-chars-14.c | 38 ++
+ gcc/testsuite/c-c++-common/Wbidi-chars-15.c | 59 +++
+ gcc/testsuite/c-c++-common/Wbidi-chars-16.c | 26 ++
+ gcc/testsuite/c-c++-common/Wbidi-chars-17.c | 30 ++
+ gcc/testsuite/c-c++-common/Wbidi-chars-2.c | 9 +
+ gcc/testsuite/c-c++-common/Wbidi-chars-3.c | 11 +
+ gcc/testsuite/c-c++-common/Wbidi-chars-4.c | 188 +++++++++
+ gcc/testsuite/c-c++-common/Wbidi-chars-5.c | 188 +++++++++
+ gcc/testsuite/c-c++-common/Wbidi-chars-6.c | 155 ++++++++
+ gcc/testsuite/c-c++-common/Wbidi-chars-7.c | 9 +
+ gcc/testsuite/c-c++-common/Wbidi-chars-8.c | 13 +
+ gcc/testsuite/c-c++-common/Wbidi-chars-9.c | 29 ++
+ libcpp/include/cpplib.h | 18 +-
+ libcpp/init.c | 1 +
+ libcpp/internal.h | 7 +
+ libcpp/lex.c | 408 +++++++++++++++++++-
+ 23 files changed, 1315 insertions(+), 7 deletions(-)
+ create mode 100644 gcc/testsuite/c-c++-common/Wbidi-chars-1.c
+ create mode 100644 gcc/testsuite/c-c++-common/Wbidi-chars-10.c
+ create mode 100644 gcc/testsuite/c-c++-common/Wbidi-chars-11.c
+ create mode 100644 gcc/testsuite/c-c++-common/Wbidi-chars-12.c
+ create mode 100644 gcc/testsuite/c-c++-common/Wbidi-chars-13.c
+ create mode 100644 gcc/testsuite/c-c++-common/Wbidi-chars-14.c
+ create mode 100644 gcc/testsuite/c-c++-common/Wbidi-chars-15.c
+ create mode 100644 gcc/testsuite/c-c++-common/Wbidi-chars-16.c
+ create mode 100644 gcc/testsuite/c-c++-common/Wbidi-chars-17.c
+ create mode 100644 gcc/testsuite/c-c++-common/Wbidi-chars-2.c
+ create mode 100644 gcc/testsuite/c-c++-common/Wbidi-chars-3.c
+ create mode 100644 gcc/testsuite/c-c++-common/Wbidi-chars-4.c
+ create mode 100644 gcc/testsuite/c-c++-common/Wbidi-chars-5.c
+ create mode 100644 gcc/testsuite/c-c++-common/Wbidi-chars-6.c
+ create mode 100644 gcc/testsuite/c-c++-common/Wbidi-chars-7.c
+ create mode 100644 gcc/testsuite/c-c++-common/Wbidi-chars-8.c
+ create mode 100644 gcc/testsuite/c-c++-common/Wbidi-chars-9.c
+
+diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt
+index 8a4cd634f77..3976fc368db 100644
+--- a/gcc/c-family/c.opt
++++ b/gcc/c-family/c.opt
+@@ -370,6 +370,30 @@ Wbad-function-cast
+ C ObjC Var(warn_bad_function_cast) Warning
+ Warn about casting functions to incompatible types.
+
++Wbidi-chars
++C ObjC C++ ObjC++ Warning Alias(Wbidi-chars=,any,none)
++;
++
++Wbidi-chars=
++C ObjC C++ ObjC++ RejectNegative Joined Warning CPP(cpp_warn_bidirectional) CppReason(CPP_W_BIDIRECTIONAL) Var(warn_bidirectional) Init(bidirectional_unpaired) Enum(cpp_bidirectional_level)
++-Wbidi-chars=[none|unpaired|any] Warn about UTF-8 bidirectional control characters.
++
++; Required for these enum values.
++SourceInclude
++cpplib.h
++
++Enum
++Name(cpp_bidirectional_level) Type(int) UnknownError(argument %qs to %<-Wbidi-chars%> not recognized)
++
++EnumValue
++Enum(cpp_bidirectional_level) String(none) Value(bidirectional_none)
++
++EnumValue
++Enum(cpp_bidirectional_level) String(unpaired) Value(bidirectional_unpaired)
++
++EnumValue
++Enum(cpp_bidirectional_level) String(any) Value(bidirectional_any)
++
+ Wbool-compare
+ C ObjC C++ ObjC++ Var(warn_bool_compare) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
+ Warn about boolean expression compared with an integer value different from true/false.
+diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
+index 6070288856c..a22758d18ee 100644
+--- a/gcc/doc/invoke.texi
++++ b/gcc/doc/invoke.texi
+@@ -326,7 +326,9 @@ Objective-C and Objective-C++ Dialects}.
+ -Warith-conversion @gol
+ -Warray-bounds -Warray-bounds=@var{n} @gol
+ -Wno-attributes -Wattribute-alias=@var{n} -Wno-attribute-alias @gol
+--Wno-attribute-warning -Wbool-compare -Wbool-operation @gol
++-Wno-attribute-warning @gol
++-Wbidi-chars=@r{[}none@r{|}unpaired@r{|}any@r{]} @gol
++-Wbool-compare -Wbool-operation @gol
+ -Wno-builtin-declaration-mismatch @gol
+ -Wno-builtin-macro-redefined -Wc90-c99-compat -Wc99-c11-compat @gol
+ -Wc11-c2x-compat @gol
+@@ -7559,6 +7561,23 @@ Attributes considered include @code{allo
+ This is the default. You can disable these warnings with either
+ @option{-Wno-attribute-alias} or @option{-Wattribute-alias=0}.
+
++@item -Wbidi-chars=@r{[}none@r{|}unpaired@r{|}any@r{]}
++@opindex Wbidi-chars=
++@opindex Wbidi-chars
++@opindex Wno-bidi-chars
++Warn about possibly misleading UTF-8 bidirectional control characters in
++comments, string literals, character constants, and identifiers. Such
++characters can change left-to-right writing direction into right-to-left
++(and vice versa), which can cause confusion between the logical order and
++visual order. This may be dangerous; for instance, it may seem that a piece
++of code is not commented out, whereas it in fact is.
++
++There are three levels of warning supported by GCC@. The default is
++@option{-Wbidi-chars=unpaired}, which warns about improperly terminated
++bidi contexts. @option{-Wbidi-chars=none} turns the warning off.
++@option{-Wbidi-chars=any} warns about any use of bidirectional control
++characters.
++
+ @item -Wbool-compare
+ @opindex Wno-bool-compare
+ @opindex Wbool-compare
+diff --git a/gcc/testsuite/c-c++-common/Wbidi-chars-10.c b/gcc/testsuite/c-c++-common/Wbidi-chars-10.c
+new file mode 100644
+index 00000000000..34f5ac19271
+--- /dev/null
++++ b/gcc/testsuite/c-c++-common/Wbidi-chars-10.c
+@@ -0,0 +1,27 @@
++/* PR preprocessor/103026 */
++/* { dg-do compile } */
++/* { dg-options "-Wbidi-chars=unpaired" } */
++/* More nesting testing. */
++
++/* RLEâ« LRI⦠PDF⬠PDIâ©*/
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int LRE_\u202a_PDF_\u202c;
++int LRE_\u202a_PDF_\u202c_LRE_\u202a_PDF_\u202c;
++int LRE_\u202a_LRI_\u2066_PDF_\u202c_PDI_\u2069;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int RLE_\u202b_RLI_\u2067_PDF_\u202c_PDI_\u2069;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int RLE_\u202b_RLI_\u2067_PDI_\u2069_PDF_\u202c;
++int FSI_\u2068_LRO_\u202d_PDI_\u2069_PDF_\u202c;
++int FSI_\u2068;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int FSI_\u2068_PDI_\u2069;
++int FSI_\u2068_FSI_\u2068_PDI_\u2069;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int RLI_\u2067_RLI_\u2067_RLI_\u2067_RLI_\u2067_RLI_\u2067_RLI_\u2067_RLI_\u2067_PDI_\u2069_PDI_\u2069_PDI_\u2069_PDI_\u2069_PDI_\u2069_PDI_\u2069_PDI_\u2069;
++int RLI_\u2067_RLI_\u2067_RLI_\u2067_RLI_\u2067_RLI_\u2067_RLI_\u2067_RLI_\u2067_PDI_\u2069_PDI_\u2069_PDI_\u2069_PDI_\u2069_PDI_\u2069_PDI_\u2069;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int RLI_\u2067_RLI_\u2067_RLI_\u2067_RLI_\u2067_RLI_\u2067_RLI_\u2067_RLI_\u2067_PDI_\u2069_PDI_\u2069_PDI_\u2069_PDI_\u2069_PDI_\u2069_PDI_\u2069_PDF_\u202c;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int RLI_\u2067_RLI_\u2067_RLI_\u2067_RLI_\u2067_FSI_\u2068_PDI_\u2069_PDI_\u2069_PDI_\u2069_PDI_\u2069;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
+diff --git a/gcc/testsuite/c-c++-common/Wbidi-chars-11.c b/gcc/testsuite/c-c++-common/Wbidi-chars-11.c
+new file mode 100644
+index 00000000000..270ce2368a9
+--- /dev/null
++++ b/gcc/testsuite/c-c++-common/Wbidi-chars-11.c
+@@ -0,0 +1,13 @@
++/* PR preprocessor/103026 */
++/* { dg-do compile } */
++/* { dg-options "-Wbidi-chars=unpaired" } */
++/* Test that we warn when mixing UCN and UTF-8. */
++
++int LRE_âª_PDF_\u202c;
++/* { dg-warning "mismatch" "" { target *-*-* } .-1 } */
++int LRE_\u202a_PDF_â¬_;
++/* { dg-warning "mismatch" "" { target *-*-* } .-1 } */
++const char *s1 = "LRE_âª_PDF_\u202c";
++/* { dg-warning "mismatch" "" { target *-*-* } .-1 } */
++const char *s2 = "LRE_\u202a_PDF_â¬";
++/* { dg-warning "mismatch" "" { target *-*-* } .-1 } */
+diff --git a/gcc/testsuite/c-c++-common/Wbidi-chars-12.c b/gcc/testsuite/c-c++-common/Wbidi-chars-12.c
+new file mode 100644
+index 00000000000..b07eec1da91
+--- /dev/null
++++ b/gcc/testsuite/c-c++-common/Wbidi-chars-12.c
+@@ -0,0 +1,19 @@
++/* PR preprocessor/103026 */
++/* { dg-do compile { target { c || c++11 } } } */
++/* { dg-options "-Wbidi-chars=any" } */
++/* Test raw strings. */
++
++const char *s1 = R"(a b c LRE⪠1 2 3 PDF⬠x y z)";
++/* { dg-warning "U\\+202A" "" { target *-*-* } .-1 } */
++const char *s2 = R"(a b c RLE⫠1 2 3 PDF⬠x y z)";
++/* { dg-warning "U\\+202B" "" { target *-*-* } .-1 } */
++const char *s3 = R"(a b c LROâ 1 2 3 PDF⬠x y z)";
++/* { dg-warning "U\\+202D" "" { target *-*-* } .-1 } */
++const char *s4 = R"(a b c RLO⮠1 2 3 PDF⬠x y z)";
++/* { dg-warning "U\\+202E" "" { target *-*-* } .-1 } */
++const char *s7 = R"(a b c FSI⨠1 2 3 PDI⩠x y) z";
++/* { dg-warning "U\\+2068" "" { target *-*-* } .-1 } */
++const char *s8 = R"(a b c PDIâ© x y )z";
++/* { dg-warning "U\\+2069" "" { target *-*-* } .-1 } */
++const char *s9 = R"(a b c PDF⬠x y z)";
++/* { dg-warning "U\\+202C" "" { target *-*-* } .-1 } */
+diff -uprN '-x*.orig' '-x*.rej' del/gcc-11.2.0/gcc/testsuite/c-c++-common/Wbidi-chars-13.c gcc-11.2.0/gcc/testsuite/c-c++-common/Wbidi-chars-13.c
+--- del/gcc-11.2.0/gcc/testsuite/c-c++-common/Wbidi-chars-13.c 1969-12-31 16:00:00.000000000 -0800
++++ gcc-11.2.0/gcc/testsuite/c-c++-common/Wbidi-chars-13.c 2021-12-13 23:11:22.328439287 -0800
+@@ -0,0 +1,17 @@
++/* PR preprocessor/103026 */
++/* { dg-do compile { target { c || c++11 } } } */
++/* { dg-options "-Wbidi-chars=unpaired" } */
++/* Test raw strings. */
++
++const char *s1 = R"(a b c LRE⪠1 2 3)";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++const char *s2 = R"(a b c RLEâ« 1 2 3)";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++const char *s3 = R"(a b c LROâ 1 2 3)";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++const char *s4 = R"(a b c FSI⨠1 2 3)";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++const char *s5 = R"(a b c LRI⦠1 2 3)";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++const char *s6 = R"(a b c RLI⧠1 2 3)";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
+diff --git a/gcc/testsuite/c-c++-common/Wbidi-chars-14.c b/gcc/testsuite/c-c++-common/Wbidi-chars-14.c
+new file mode 100644
+index 00000000000..ba5f75d9553
+--- /dev/null
++++ b/gcc/testsuite/c-c++-common/Wbidi-chars-14.c
+@@ -0,0 +1,38 @@
++/* PR preprocessor/103026 */
++/* { dg-do compile } */
++/* { dg-options "-Wbidi-chars=unpaired" } */
++/* Test PDI handling, which also pops any subsequent LREs, RLEs, LROs,
++ or RLOs. */
++
++/* LRI_â¦_LRI_â¦_RLE_â«_RLE_â«_RLE_â«_PDI_â©*/
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++// LRI_â¦_RLE_â«_RLE_â«_RLE_â«_PDI_â©
++// LRI_â¦_RLO_â®_RLE_â«_RLE_â«_PDI_â©
++// LRI_â¦_RLO_â®_RLE_â«_PDI_â©
++// FSI_â¨_RLO_â®_PDI_â©
++// FSI_â¨_FSI_â¨_RLO_â®_PDI_â©
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++
++int LRI_\u2066_LRI_\u2066_LRE_\u202a_LRE_\u202a_LRE_\u202a_PDI_\u2069;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int LRI_\u2066_LRI_\u2066_LRE_\u202a_LRE_\u202a_LRE_\u202a_PDI_\u2069_PDI_\u2069;
++int LRI_\u2066_LRI_\u2066_LRI_\u2066_LRE_\u202a_LRE_\u202a_LRE_\u202a_PDI_\u2069_PDI_\u2069;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int PDI_\u2069;
++int LRI_\u2066_PDI_\u2069;
++int RLI_\u2067_PDI_\u2069;
++int LRE_\u202a_LRI_\u2066_PDI_\u2069;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int LRI_\u2066_LRE_\u202a_PDF_\u202c_PDI_\u2069;
++int LRI_\u2066_LRE_\u202a_LRE_\u202a_PDF_\u202c_PDI_\u2069;
++int RLI_\u2067_LRI_\u2066_LRE_\u202a_LRE_\u202a_PDF_\u202c_PDI_\u2069;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int FSI_\u2068_LRI_\u2066_LRE_\u202a_LRE_\u202a_PDF_\u202c_PDI_\u2069;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int RLO_\u202e_PDI_\u2069;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int RLI_\u2067_PDI_\u2069_RLI_\u2067;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int FSI_\u2068_PDF_\u202c_PDI_\u2069;
++int FSI_\u2068_FSI_\u2068_PDF_\u202c_PDI_\u2069;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
+diff --git a/gcc/testsuite/c-c++-common/Wbidi-chars-15.c b/gcc/testsuite/c-c++-common/Wbidi-chars-15.c
+new file mode 100644
+index 00000000000..a0ce8ff5e2c
+--- /dev/null
++++ b/gcc/testsuite/c-c++-common/Wbidi-chars-15.c
+@@ -0,0 +1,59 @@
++/* PR preprocessor/103026 */
++/* { dg-do compile } */
++/* { dg-options "-Wbidi-chars=unpaired" } */
++/* Test unpaired bidi control chars in multiline comments. */
++
++/*
++ * LRE⪠end
++ */
++/* { dg-warning "unpaired" "" { target *-*-* } .-2 } */
++/*
++ * RLEâ« end
++ */
++/* { dg-warning "unpaired" "" { target *-*-* } .-2 } */
++/*
++ * LROâ end
++ */
++/* { dg-warning "unpaired" "" { target *-*-* } .-2 } */
++/*
++ * RLOâ® end
++ */
++/* { dg-warning "unpaired" "" { target *-*-* } .-2 } */
++/*
++ * LRI⦠end
++ */
++/* { dg-warning "unpaired" "" { target *-*-* } .-2 } */
++/*
++ * RLI⧠end
++ */
++/* { dg-warning "unpaired" "" { target *-*-* } .-2 } */
++/*
++ * FSI⨠end
++ */
++/* { dg-warning "unpaired" "" { target *-*-* } .-2 } */
++/* LREâª
++ PDF⬠*/
++/* { dg-warning "unpaired" "" { target *-*-* } .-2 } */
++/* FSIâ¨
++ PDIâ© */
++/* { dg-warning "unpaired" "" { target *-*-* } .-2 } */
++
++/* LRE<âª>
++ *
++ */
++/* { dg-warning "unpaired" "" { target *-*-* } .-3 } */
++
++/*
++ * LRE<âª>
++ */
++/* { dg-warning "unpaired" "" { target *-*-* } .-2 } */
++
++/*
++ *
++ * LRE<âª> */
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++
++/* RLI<â§> */ /* PDI<â©> */
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++/* LRE<âª> */ /* PDF<â¬> */
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
+diff --git a/gcc/testsuite/c-c++-common/Wbidi-chars-16.c b/gcc/testsuite/c-c++-common/Wbidi-chars-16.c
+new file mode 100644
+index 00000000000..baa0159861c
+--- /dev/null
++++ b/gcc/testsuite/c-c++-common/Wbidi-chars-16.c
+@@ -0,0 +1,26 @@
++/* PR preprocessor/103026 */
++/* { dg-do compile } */
++/* { dg-options "-Wbidi-chars=any" } */
++/* Test LTR/RTL chars. */
++
++/* LTR<â> */
++/* { dg-warning "U\\+200E" "" { target *-*-* } .-1 } */
++// LTR<â>
++/* { dg-warning "U\\+200E" "" { target *-*-* } .-1 } */
++/* RTL<â> */
++/* { dg-warning "U\\+200F" "" { target *-*-* } .-1 } */
++// RTL<â>
++/* { dg-warning "U\\+200F" "" { target *-*-* } .-1 } */
++
++const char *s1 = "LTR<â>";
++/* { dg-warning "U\\+200E" "" { target *-*-* } .-1 } */
++const char *s2 = "LTR\u200e";
++/* { dg-warning "U\\+200E" "" { target *-*-* } .-1 } */
++const char *s3 = "LTR\u200E";
++/* { dg-warning "U\\+200E" "" { target *-*-* } .-1 } */
++const char *s4 = "RTL<â>";
++/* { dg-warning "U\\+200F" "" { target *-*-* } .-1 } */
++const char *s5 = "RTL\u200f";
++/* { dg-warning "U\\+200F" "" { target *-*-* } .-1 } */
++const char *s6 = "RTL\u200F";
++/* { dg-warning "U\\+200F" "" { target *-*-* } .-1 } */
+diff --git a/gcc/testsuite/c-c++-common/Wbidi-chars-17.c b/gcc/testsuite/c-c++-common/Wbidi-chars-17.c
+new file mode 100644
+index 00000000000..07cb4321f96
+--- /dev/null
++++ b/gcc/testsuite/c-c++-common/Wbidi-chars-17.c
+@@ -0,0 +1,30 @@
++/* PR preprocessor/103026 */
++/* { dg-do compile } */
++/* { dg-options "-Wbidi-chars=unpaired" } */
++/* Test LTR/RTL chars. */
++
++/* LTR<â> */
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++// LTR<â>
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++/* RTL<â> */
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++// RTL<â>
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int ltr_\u200e;
++/* { dg-error "universal character " "" { target *-*-* } .-1 } */
++int rtl_\u200f;
++/* { dg-error "universal character " "" { target *-*-* } .-1 } */
++
++const char *s1 = "LTR<â>";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++const char *s2 = "LTR\u200e";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++const char *s3 = "LTR\u200E";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++const char *s4 = "RTL<â>";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++const char *s5 = "RTL\u200f";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++const char *s6 = "RTL\u200F";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
+diff --git a/gcc/testsuite/c-c++-common/Wbidi-chars-1.c b/gcc/testsuite/c-c++-common/Wbidi-chars-1.c
+new file mode 100644
+index 00000000000..2340374f276
+--- /dev/null
++++ b/gcc/testsuite/c-c++-common/Wbidi-chars-1.c
+@@ -0,0 +1,12 @@
++/* PR preprocessor/103026 */
++/* { dg-do compile } */
++
++int main() {
++ int isAdmin = 0;
++ /*â® } â¦if (isAdmin)⩠⦠begin admins only */
++/* { dg-warning "bidirectional" "" { target *-*-* } .-1 } */
++ __builtin_printf("You are an admin.\n");
++ /* end admins only â® { â¦*/
++/* { dg-warning "bidirectional" "" { target *-*-* } .-1 } */
++ return 0;
++}
+diff --git a/gcc/testsuite/c-c++-common/Wbidi-chars-2.c b/gcc/testsuite/c-c++-common/Wbidi-chars-2.c
+new file mode 100644
+index 00000000000..2340374f276
+--- /dev/null
++++ b/gcc/testsuite/c-c++-common/Wbidi-chars-2.c
+@@ -0,0 +1,9 @@
++/* PR preprocessor/103026 */
++/* { dg-do compile } */
++
++int main() {
++ /* Say hello; newlineâ§/*/ return 0 ;
++/* { dg-warning "bidirectional" "" { target *-*-* } .-1 } */
++ __builtin_printf("Hello world.\n");
++ return 0;
++}
+diff --git a/gcc/testsuite/c-c++-common/Wbidi-chars-3.c b/gcc/testsuite/c-c++-common/Wbidi-chars-3.c
+new file mode 100644
+index 00000000000..9dc7edb6e64
+--- /dev/null
++++ b/gcc/testsuite/c-c++-common/Wbidi-chars-3.c
+@@ -0,0 +1,11 @@
++/* PR preprocessor/103026 */
++/* { dg-do compile } */
++
++int main() {
++ const char* access_level = "user";
++ if (__builtin_strcmp(access_level, "userâ® â¦// Check if adminâ© â¦")) {
++/* { dg-warning "bidirectional" "" { target *-*-* } .-1 } */
++ __builtin_printf("You are an admin.\n");
++ }
++ return 0;
++}
+diff --git a/gcc/testsuite/c-c++-common/Wbidi-chars-4.c b/gcc/testsuite/c-c++-common/Wbidi-chars-4.c
+new file mode 100644
+index 00000000000..639e5c62e88
+--- /dev/null
++++ b/gcc/testsuite/c-c++-common/Wbidi-chars-4.c
+@@ -0,0 +1,188 @@
++/* PR preprocessor/103026 */
++/* { dg-do compile } */
++/* { dg-options "-Wbidi-chars=any -Wno-multichar -Wno-overflow" } */
++/* Test all bidi chars in various contexts (identifiers, comments,
++ string literals, character constants), both UCN and UTF-8. The bidi
++ chars here are properly terminated, except for the character constants. */
++
++/* a b c LRE⪠1 2 3 PDF⬠x y z */
++/* { dg-warning "U\\+202A" "" { target *-*-* } .-1 } */
++/* a b c RLE⫠1 2 3 PDF⬠x y z */
++/* { dg-warning "U\\+202B" "" { target *-*-* } .-1 } */
++/* a b c LROâ 1 2 3 PDF⬠x y z */
++/* { dg-warning "U\\+202D" "" { target *-*-* } .-1 } */
++/* a b c RLO⮠1 2 3 PDF⬠x y z */
++/* { dg-warning "U\\+202E" "" { target *-*-* } .-1 } */
++/* a b c LRI⦠1 2 3 PDI⩠x y z */
++/* { dg-warning "U\\+2066" "" { target *-*-* } .-1 } */
++/* a b c RLI⧠1 2 3 PDI⩠x y */
++/* { dg-warning "U\\+2067" "" { target *-*-* } .-1 } */
++/* a b c FSI⨠1 2 3 PDI⩠x y z */
++/* { dg-warning "U\\+2068" "" { target *-*-* } .-1 } */
++
++/* Same but C++ comments instead. */
++// a b c LRE⪠1 2 3 PDF⬠x y z
++/* { dg-warning "U\\+202A" "" { target *-*-* } .-1 } */
++// a b c RLE⫠1 2 3 PDF⬠x y z
++/* { dg-warning "U\\+202B" "" { target *-*-* } .-1 } */
++// a b c LROâ 1 2 3 PDF⬠x y z
++/* { dg-warning "U\\+202D" "" { target *-*-* } .-1 } */
++// a b c RLO⮠1 2 3 PDF⬠x y z
++/* { dg-warning "U\\+202E" "" { target *-*-* } .-1 } */
++// a b c LRI⦠1 2 3 PDI⩠x y z
++/* { dg-warning "U\\+2066" "" { target *-*-* } .-1 } */
++// a b c RLI⧠1 2 3 PDI⩠x y
++/* { dg-warning "U\\+2067" "" { target *-*-* } .-1 } */
++// a b c FSI⨠1 2 3 PDI⩠x y z
++/* { dg-warning "U\\+2068" "" { target *-*-* } .-1 } */
++
++/* Here we're closing an unopened context, warn when =any. */
++/* a b c PDIâ© x y z */
++/* { dg-warning "U\\+2069" "" { target *-*-* } .-1 } */
++/* a b c PDF⬠x y z */
++/* { dg-warning "U\\+202C" "" { target *-*-* } .-1 } */
++// a b c PDIâ© x y z
++/* { dg-warning "U\\+2069" "" { target *-*-* } .-1 } */
++// a b c PDF⬠x y z
++/* { dg-warning "U\\+202C" "" { target *-*-* } .-1 } */
++
++/* Multiline comments. */
++/* a b c PDIâ© x y z
++ */
++/* { dg-warning "U\\+2069" "" { target *-*-* } .-2 } */
++/* a b c PDF⬠x y z
++ */
++/* { dg-warning "U\\+202C" "" { target *-*-* } .-2 } */
++/* first
++ a b c PDIâ© x y z
++ */
++/* { dg-warning "U\\+2069" "" { target *-*-* } .-2 } */
++/* first
++ a b c PDF⬠x y z
++ */
++/* { dg-warning "U\\+202C" "" { target *-*-* } .-2 } */
++/* first
++ a b c PDIâ© x y z */
++/* { dg-warning "U\\+2069" "" { target *-*-* } .-1 } */
++/* first
++ a b c PDF⬠x y z */
++/* { dg-warning "U\\+202C" "" { target *-*-* } .-1 } */
++
++void
++g1 ()
++{
++ const char *s1 = "a b c LRE⪠1 2 3 PDF⬠x y z";
++/* { dg-warning "U\\+202A" "" { target *-*-* } .-1 } */
++ const char *s2 = "a b c RLE⫠1 2 3 PDF⬠x y z";
++/* { dg-warning "U\\+202B" "" { target *-*-* } .-1 } */
++ const char *s3 = "a b c LROâ 1 2 3 PDF⬠x y z";
++/* { dg-warning "U\\+202D" "" { target *-*-* } .-1 } */
++ const char *s4 = "a b c RLO⮠1 2 3 PDF⬠x y z";
++/* { dg-warning "U\\+202E" "" { target *-*-* } .-1 } */
++ const char *s5 = "a b c LRI⦠1 2 3 PDI⩠x y z";
++/* { dg-warning "U\\+2066" "" { target *-*-* } .-1 } */
++ const char *s6 = "a b c RLI⧠1 2 3 PDI⩠x y z";
++/* { dg-warning "U\\+2067" "" { target *-*-* } .-1 } */
++ const char *s7 = "a b c FSI⨠1 2 3 PDI⩠x y z";
++/* { dg-warning "U\\+2068" "" { target *-*-* } .-1 } */
++ const char *s8 = "a b c PDIâ© x y z";
++/* { dg-warning "U\\+2069" "" { target *-*-* } .-1 } */
++ const char *s9 = "a b c PDF⬠x y z";
++/* { dg-warning "U\\+202C" "" { target *-*-* } .-1 } */
++
++ const char *s10 = "a b c LRE\u202a 1 2 3 PDF\u202c x y z";
++/* { dg-warning "U\\+202A" "" { target *-*-* } .-1 } */
++ const char *s11 = "a b c LRE\u202A 1 2 3 PDF\u202c x y z";
++/* { dg-warning "U\\+202A" "" { target *-*-* } .-1 } */
++ const char *s12 = "a b c RLE\u202b 1 2 3 PDF\u202c x y z";
++/* { dg-warning "U\\+202B" "" { target *-*-* } .-1 } */
++ const char *s13 = "a b c RLE\u202B 1 2 3 PDF\u202c x y z";
++/* { dg-warning "U\\+202B" "" { target *-*-* } .-1 } */
++ const char *s14 = "a b c LRO\u202d 1 2 3 PDF\u202c x y z";
++/* { dg-warning "U\\+202D" "" { target *-*-* } .-1 } */
++ const char *s15 = "a b c LRO\u202D 1 2 3 PDF\u202c x y z";
++/* { dg-warning "U\\+202D" "" { target *-*-* } .-1 } */
++ const char *s16 = "a b c RLO\u202e 1 2 3 PDF\u202c x y z";
++/* { dg-warning "U\\+202E" "" { target *-*-* } .-1 } */
++ const char *s17 = "a b c RLO\u202E 1 2 3 PDF\u202c x y z";
++/* { dg-warning "U\\+202E" "" { target *-*-* } .-1 } */
++ const char *s18 = "a b c LRI\u2066 1 2 3 PDI\u2069 x y z";
++/* { dg-warning "U\\+2066" "" { target *-*-* } .-1 } */
++ const char *s19 = "a b c RLI\u2067 1 2 3 PDI\u2069 x y z";
++/* { dg-warning "U\\+2067" "" { target *-*-* } .-1 } */
++ const char *s20 = "a b c FSI\u2068 1 2 3 PDI\u2069 x y z";
++/* { dg-warning "U\\+2068" "" { target *-*-* } .-1 } */
++}
++
++void
++g2 ()
++{
++ const char c1 = '\u202a';
++/* { dg-warning "U\\+202A" "" { target *-*-* } .-1 } */
++ const char c2 = '\u202A';
++/* { dg-warning "U\\+202A" "" { target *-*-* } .-1 } */
++ const char c3 = '\u202b';
++/* { dg-warning "U\\+202B" "" { target *-*-* } .-1 } */
++ const char c4 = '\u202B';
++/* { dg-warning "U\\+202B" "" { target *-*-* } .-1 } */
++ const char c5 = '\u202d';
++/* { dg-warning "U\\+202D" "" { target *-*-* } .-1 } */
++ const char c6 = '\u202D';
++/* { dg-warning "U\\+202D" "" { target *-*-* } .-1 } */
++ const char c7 = '\u202e';
++/* { dg-warning "U\\+202E" "" { target *-*-* } .-1 } */
++ const char c8 = '\u202E';
++/* { dg-warning "U\\+202E" "" { target *-*-* } .-1 } */
++ const char c9 = '\u2066';
++/* { dg-warning "U\\+2066" "" { target *-*-* } .-1 } */
++ const char c10 = '\u2067';
++/* { dg-warning "U\\+2067" "" { target *-*-* } .-1 } */
++ const char c11 = '\u2068';
++/* { dg-warning "U\\+2068" "" { target *-*-* } .-1 } */
++}
++
++int aâªbâ¬c;
++/* { dg-warning "U\\+202A" "" { target *-*-* } .-1 } */
++int aâ«bâ¬c;
++/* { dg-warning "U\\+202B" "" { target *-*-* } .-1 } */
++int aâbâ¬c;
++/* { dg-warning "U\\+202D" "" { target *-*-* } .-1 } */
++int aâ®bâ¬c;
++/* { dg-warning "U\\+202E" "" { target *-*-* } .-1 } */
++int aâ¦bâ©c;
++/* { dg-warning "U\\+2066" "" { target *-*-* } .-1 } */
++int aâ§bâ©c;
++/* { dg-warning "U\\+2067" "" { target *-*-* } .-1 } */
++int aâ¨bâ©c;
++/* { dg-warning "U\\+2068" "" { target *-*-* } .-1 } */
++int Aâ¬X;
++/* { dg-warning "U\\+202C" "" { target *-*-* } .-1 } */
++int A\u202cY;
++/* { dg-warning "U\\+202C" "" { target *-*-* } .-1 } */
++int A\u202CY2;
++/* { dg-warning "U\\+202C" "" { target *-*-* } .-1 } */
++
++int d\u202ae\u202cf;
++/* { dg-warning "U\\+202A" "" { target *-*-* } .-1 } */
++int d\u202Ae\u202cf2;
++/* { dg-warning "U\\+202A" "" { target *-*-* } .-1 } */
++int d\u202be\u202cf;
++/* { dg-warning "U\\+202B" "" { target *-*-* } .-1 } */
++int d\u202Be\u202cf2;
++/* { dg-warning "U\\+202B" "" { target *-*-* } .-1 } */
++int d\u202de\u202cf;
++/* { dg-warning "U\\+202D" "" { target *-*-* } .-1 } */
++int d\u202De\u202cf2;
++/* { dg-warning "U\\+202D" "" { target *-*-* } .-1 } */
++int d\u202ee\u202cf;
++/* { dg-warning "U\\+202E" "" { target *-*-* } .-1 } */
++int d\u202Ee\u202cf2;
++/* { dg-warning "U\\+202E" "" { target *-*-* } .-1 } */
++int d\u2066e\u2069f;
++/* { dg-warning "U\\+2066" "" { target *-*-* } .-1 } */
++int d\u2067e\u2069f;
++/* { dg-warning "U\\+2067" "" { target *-*-* } .-1 } */
++int d\u2068e\u2069f;
++/* { dg-warning "U\\+2068" "" { target *-*-* } .-1 } */
++int X\u2069;
++/* { dg-warning "U\\+2069" "" { target *-*-* } .-1 } */
+diff --git a/gcc/testsuite/c-c++-common/Wbidi-chars-5.c b/gcc/testsuite/c-c++-common/Wbidi-chars-5.c
+new file mode 100644
+index 00000000000..68cb053144b
+--- /dev/null
++++ b/gcc/testsuite/c-c++-common/Wbidi-chars-5.c
+@@ -0,0 +1,188 @@
++/* PR preprocessor/103026 */
++/* { dg-do compile } */
++/* { dg-options "-Wbidi-chars=unpaired -Wno-multichar -Wno-overflow" } */
++/* Test all bidi chars in various contexts (identifiers, comments,
++ string literals, character constants), both UCN and UTF-8. The bidi
++ chars here are properly terminated, except for the character constants. */
++
++/* a b c LRE⪠1 2 3 PDF⬠x y z */
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++/* a b c RLE⫠1 2 3 PDF⬠x y z */
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++/* a b c LROâ 1 2 3 PDF⬠x y z */
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++/* a b c RLO⮠1 2 3 PDF⬠x y z */
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++/* a b c LRI⦠1 2 3 PDI⩠x y z */
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++/* a b c RLI⧠1 2 3 PDI⩠x y */
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++/* a b c FSI⨠1 2 3 PDI⩠x y z */
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++
++/* Same but C++ comments instead. */
++// a b c LRE⪠1 2 3 PDF⬠x y z
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++// a b c RLE⫠1 2 3 PDF⬠x y z
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++// a b c LROâ 1 2 3 PDF⬠x y z
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++// a b c RLO⮠1 2 3 PDF⬠x y z
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++// a b c LRI⦠1 2 3 PDI⩠x y z
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++// a b c RLI⧠1 2 3 PDI⩠x y
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++// a b c FSI⨠1 2 3 PDI⩠x y z
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++
++/* Here we're closing an unopened context, warn when =any. */
++/* a b c PDIâ© x y z */
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++/* a b c PDF⬠x y z */
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++// a b c PDIâ© x y z
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++// a b c PDF⬠x y z
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++
++/* Multiline comments. */
++/* a b c PDIâ© x y z
++ */
++/* { dg-bogus "unpaired" "" { target *-*-* } .-2 } */
++/* a b c PDF⬠x y z
++ */
++/* { dg-bogus "unpaired" "" { target *-*-* } .-2 } */
++/* first
++ a b c PDIâ© x y z
++ */
++/* { dg-bogus "unpaired" "" { target *-*-* } .-2 } */
++/* first
++ a b c PDF⬠x y z
++ */
++/* { dg-bogus "unpaired" "" { target *-*-* } .-2 } */
++/* first
++ a b c PDIâ© x y z */
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++/* first
++ a b c PDF⬠x y z */
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++
++void
++g1 ()
++{
++ const char *s1 = "a b c LRE⪠1 2 3 PDF⬠x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++ const char *s2 = "a b c RLE⫠1 2 3 PDF⬠x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++ const char *s3 = "a b c LROâ 1 2 3 PDF⬠x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++ const char *s4 = "a b c RLO⮠1 2 3 PDF⬠x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++ const char *s5 = "a b c LRI⦠1 2 3 PDI⩠x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++ const char *s6 = "a b c RLI⧠1 2 3 PDI⩠x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++ const char *s7 = "a b c FSI⨠1 2 3 PDI⩠x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++ const char *s8 = "a b c PDIâ© x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++ const char *s9 = "a b c PDF⬠x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++
++ const char *s10 = "a b c LRE\u202a 1 2 3 PDF\u202c x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++ const char *s11 = "a b c LRE\u202A 1 2 3 PDF\u202c x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++ const char *s12 = "a b c RLE\u202b 1 2 3 PDF\u202c x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++ const char *s13 = "a b c RLE\u202B 1 2 3 PDF\u202c x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++ const char *s14 = "a b c LRO\u202d 1 2 3 PDF\u202c x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++ const char *s15 = "a b c LRO\u202D 1 2 3 PDF\u202c x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++ const char *s16 = "a b c RLO\u202e 1 2 3 PDF\u202c x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++ const char *s17 = "a b c RLO\u202E 1 2 3 PDF\u202c x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++ const char *s18 = "a b c LRI\u2066 1 2 3 PDI\u2069 x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++ const char *s19 = "a b c RLI\u2067 1 2 3 PDI\u2069 x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++ const char *s20 = "a b c FSI\u2068 1 2 3 PDI\u2069 x y z";
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++}
++
++void
++g2 ()
++{
++ const char c1 = '\u202a';
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char c2 = '\u202A';
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char c3 = '\u202b';
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char c4 = '\u202B';
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char c5 = '\u202d';
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char c6 = '\u202D';
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char c7 = '\u202e';
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char c8 = '\u202E';
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char c9 = '\u2066';
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char c10 = '\u2067';
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char c11 = '\u2068';
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++}
++
++int aâªbâ¬c;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int aâ«bâ¬c;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int aâbâ¬c;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int aâ®bâ¬c;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int aâ¦bâ©c;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int aâ§bâ©c;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int aâ¨bâ©c;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int Aâ¬X;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int A\u202cY;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int A\u202CY2;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++
++int d\u202ae\u202cf;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int d\u202Ae\u202cf2;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int d\u202be\u202cf;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int d\u202Be\u202cf2;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int d\u202de\u202cf;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int d\u202De\u202cf2;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int d\u202ee\u202cf;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int d\u202Ee\u202cf2;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int d\u2066e\u2069f;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int d\u2067e\u2069f;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int d\u2068e\u2069f;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
++int X\u2069;
++/* { dg-bogus "unpaired" "" { target *-*-* } .-1 } */
+diff --git a/gcc/testsuite/c-c++-common/Wbidi-chars-6.c b/gcc/testsuite/c-c++-common/Wbidi-chars-6.c
+new file mode 100644
+index 00000000000..0ce6fff2dee
+--- /dev/null
++++ b/gcc/testsuite/c-c++-common/Wbidi-chars-6.c
+@@ -0,0 +1,155 @@
++/* PR preprocessor/103026 */
++/* { dg-do compile } */
++/* { dg-options "-Wbidi-chars=unpaired" } */
++/* Test nesting of bidi chars in various contexts. */
++
++/* Terminated by the wrong char: */
++/* a b c LRE⪠1 2 3 PDI⩠x y z */
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++/* a b c RLEâ« 1 2 3 PDIâ© x y z*/
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++/* a b c LROâ 1 2 3 PDIâ© x y z */
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++/* a b c RLOâ® 1 2 3 PDIâ© x y z */
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++/* a b c LRI⦠1 2 3 PDF⬠x y z */
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++/* a b c RLI⧠1 2 3 PDF⬠x y z */
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++/* a b c FSI⨠1 2 3 PDF⬠x y z*/
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++
++/* LRE⪠PDF⬠*/
++/* LRE⪠LRE⪠PDF⬠PDF⬠*/
++/* PDF⬠LRE⪠PDF⬠*/
++/* LRE⪠PDF⬠LRE⪠PDF⬠*/
++/* LRE⪠LRE⪠PDF⬠*/
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++/* PDF⬠LRE⪠*/
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++
++// a b c LRE⪠1 2 3 PDI⩠x y z
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++// a b c RLEâ« 1 2 3 PDIâ© x y z*/
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++// a b c LROâ 1 2 3 PDIâ© x y z
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++// a b c RLOâ® 1 2 3 PDIâ© x y z
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++// a b c LRI⦠1 2 3 PDF⬠x y z
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++// a b c RLI⧠1 2 3 PDF⬠x y z
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++// a b c FSI⨠1 2 3 PDF⬠x y z
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++
++// LRE⪠PDFâ¬
++// LRE⪠LRE⪠PDF⬠PDFâ¬
++// PDF⬠LRE⪠PDFâ¬
++// LRE⪠PDF⬠LRE⪠PDFâ¬
++// LRE⪠LRE⪠PDFâ¬
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++// PDF⬠LREâª
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++
++void
++g1 ()
++{
++ const char *s1 = "a b c LRE⪠1 2 3 PDI⩠x y z";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s2 = "a b c LRE\u202a 1 2 3 PDI\u2069 x y z";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s3 = "a b c RLEâ« 1 2 3 PDIâ© x y ";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s4 = "a b c RLE\u202b 1 2 3 PDI\u2069 x y z";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s5 = "a b c LROâ 1 2 3 PDIâ© x y z";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s6 = "a b c LRO\u202d 1 2 3 PDI\u2069 x y z";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s7 = "a b c RLOâ® 1 2 3 PDIâ© x y z";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s8 = "a b c RLO\u202e 1 2 3 PDI\u2069 x y z";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s9 = "a b c LRI⦠1 2 3 PDF⬠x y z";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s10 = "a b c LRI\u2066 1 2 3 PDF\u202c x y z";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s11 = "a b c RLI⧠1 2 3 PDF⬠x y z\
++ ";
++/* { dg-warning "unpaired" "" { target *-*-* } .-2 } */
++ const char *s12 = "a b c RLI\u2067 1 2 3 PDF\u202c x y z";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s13 = "a b c FSI⨠1 2 3 PDF⬠x y z";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s14 = "a b c FSI\u2068 1 2 3 PDF\u202c x y z";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s15 = "PDF⬠LREâª";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s16 = "PDF\u202c LRE\u202a";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s17 = "LRE⪠PDFâ¬";
++ const char *s18 = "LRE\u202a PDF\u202c";
++ const char *s19 = "LRE⪠LRE⪠PDF⬠PDFâ¬";
++ const char *s20 = "LRE\u202a LRE\u202a PDF\u202c PDF\u202c";
++ const char *s21 = "PDF⬠LRE⪠PDFâ¬";
++ const char *s22 = "PDF\u202c LRE\u202a PDF\u202c";
++ const char *s23 = "LRE⪠LRE⪠PDFâ¬";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s24 = "LRE\u202a LRE\u202a PDF\u202c";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s25 = "PDF⬠LREâª";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s26 = "PDF\u202c LRE\u202a";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s27 = "PDF⬠LRE\u202a";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++ const char *s28 = "PDF\u202c LREâª";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++}
++
++int aLREâªbPDIâ©;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int A\u202aB\u2069C;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int aRLEâ«bPDIâ©;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int a\u202bB\u2069c;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int aLROâbPDIâ©;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int a\u202db\u2069c2;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int aRLOâ®bPDIâ©;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int a\u202eb\u2069;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int aLRIâ¦bPDFâ¬;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int a\u2066b\u202c;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int aRLIâ§bPDFâ¬c
++;
++/* { dg-warning "unpaired" "" { target *-*-* } .-2 } */
++int a\u2067b\u202c;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int aFSIâ¨bPDFâ¬;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int a\u2068b\u202c;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int aFSIâ¨bPD\u202C;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int aFSI\u2068bPDFâ¬_;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int aLREâªbPDFâ¬b;
++int A\u202aB\u202c;
++int a_LREâª_LREâª_b_PDFâ¬_PDFâ¬;
++int A\u202aA\u202aB\u202cB\u202c;
++int aPDFâ¬bLREadPDFâ¬;
++int a_\u202C_\u202a_\u202c;
++int a_LREâª_b_PDFâ¬_c_LREâª_PDFâ¬;
++int a_\u202a_\u202c_\u202a_\u202c_;
++int a_LREâª_b_PDFâ¬_c_LREâª;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int a_\u202a_\u202c_\u202a_;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
+diff --git a/gcc/testsuite/c-c++-common/Wbidi-chars-7.c b/gcc/testsuite/c-c++-common/Wbidi-chars-7.c
+new file mode 100644
+index 00000000000..d012d420ec0
+--- /dev/null
++++ b/gcc/testsuite/c-c++-common/Wbidi-chars-7.c
+@@ -0,0 +1,9 @@
++/* PR preprocessor/103026 */
++/* { dg-do compile } */
++/* { dg-options "-Wbidi-chars=any" } */
++/* Test we ignore UCNs in comments. */
++
++// a b c \u202a 1 2 3
++// a b c \u202A 1 2 3
++/* a b c \u202a 1 2 3 */
++/* a b c \u202A 1 2 3 */
+diff --git a/gcc/testsuite/c-c++-common/Wbidi-chars-8.c b/gcc/testsuite/c-c++-common/Wbidi-chars-8.c
+new file mode 100644
+index 00000000000..4f54c5092ec
+--- /dev/null
++++ b/gcc/testsuite/c-c++-common/Wbidi-chars-8.c
+@@ -0,0 +1,13 @@
++/* PR preprocessor/103026 */
++/* { dg-do compile } */
++/* { dg-options "-Wbidi-chars=any" } */
++/* Test \u vs \U. */
++
++int a_\u202A;
++/* { dg-warning "U\\+202A" "" { target *-*-* } .-1 } */
++int a_\u202a_2;
++/* { dg-warning "U\\+202A" "" { target *-*-* } .-1 } */
++int a_\U0000202A_3;
++/* { dg-warning "U\\+202A" "" { target *-*-* } .-1 } */
++int a_\U0000202a_4;
++/* { dg-warning "U\\+202A" "" { target *-*-* } .-1 } */
+diff --git a/gcc/testsuite/c-c++-common/Wbidi-chars-9.c b/gcc/testsuite/c-c++-common/Wbidi-chars-9.c
+new file mode 100644
+index 00000000000..e2af1b1ca97
+--- /dev/null
++++ b/gcc/testsuite/c-c++-common/Wbidi-chars-9.c
+@@ -0,0 +1,29 @@
++/* PR preprocessor/103026 */
++/* { dg-do compile } */
++/* { dg-options "-Wbidi-chars=unpaired" } */
++/* Test that we properly separate bidi contexts (comment/identifier/character
++ constant/string literal). */
++
++/* LRE ->âª<- */ int pdf_\u202c_1;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++/* RLE ->â«<- */ int pdf_\u202c_2;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++/* LRO ->â<- */ int pdf_\u202c_3;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++/* RLO ->â®<- */ int pdf_\u202c_4;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++/* LRI ->â¦<-*/ int pdi_\u2069_1;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++/* RLI ->â§<- */ int pdi_\u2069_12;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++/* FSI ->â¨<- */ int pdi_\u2069_3;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++
++const char *s1 = "LRE\u202a"; /* PDF ->â¬<- */
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++/* LRE ->âª<- */ const char *s2 = "PDF\u202c";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++const char *s3 = "LRE\u202a"; int pdf_\u202c_5;
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
++int lre_\u202a; const char *s4 = "PDF\u202c";
++/* { dg-warning "unpaired" "" { target *-*-* } .-1 } */
+diff --git a/libcpp/include/cpplib.h b/libcpp/include/cpplib.h
+index 176f8c5bbce..112b9c24751 100644
+--- a/libcpp/include/cpplib.h
++++ b/libcpp/include/cpplib.h
+@@ -318,6 +318,17 @@ enum cpp_main_search
+ CMS_system, /* Search the system INCLUDE path. */
+ };
+
++/* The possible bidirectional control characters checking levels, from least
++ restrictive to most. */
++enum cpp_bidirectional_level {
++ /* No checking. */
++ bidirectional_none,
++ /* Only detect unpaired uses of bidirectional control characters. */
++ bidirectional_unpaired,
++ /* Detect any use of bidirectional control characters. */
++ bidirectional_any
++};
++
+ /* This structure is nested inside struct cpp_reader, and
+ carries all the options visible to the command line. */
+ struct cpp_options
+@@ -531,6 +542,10 @@ struct cpp_options
+ /* True if warn about differences between C++98 and C++11. */
+ bool cpp_warn_cxx11_compat;
+
++ /* Nonzero if bidirectional control characters checking is on. See enum
++ cpp_bidirectional_level. */
++ unsigned char cpp_warn_bidirectional;
++
+ /* Dependency generation. */
+ struct
+ {
+@@ -635,7 +650,8 @@ enum cpp_warning_reason {
+ CPP_W_C90_C99_COMPAT,
+ CPP_W_C11_C2X_COMPAT,
+ CPP_W_CXX11_COMPAT,
+- CPP_W_EXPANSION_TO_DEFINED
++ CPP_W_EXPANSION_TO_DEFINED,
++ CPP_W_BIDIRECTIONAL
+ };
+
+ /* Callback for header lookup for HEADER, which is the name of a
+diff --git a/libcpp/init.c b/libcpp/init.c
+index 5a424e23553..f9a8f5f088f 100644
+--- a/libcpp/init.c
++++ b/libcpp/init.c
+@@ -219,6 +219,7 @@ cpp_create_reader (enum c_lang lang, cpp
+ = ENABLE_CANONICAL_SYSTEM_HEADERS;
+ CPP_OPTION (pfile, ext_numeric_literals) = 1;
+ CPP_OPTION (pfile, warn_date_time) = 0;
++ CPP_OPTION (pfile, cpp_warn_bidirectional) = bidirectional_unpaired;
+
+ /* Default CPP arithmetic to something sensible for the host for the
+ benefit of dumb users like fix-header. */
+diff --git a/libcpp/internal.h b/libcpp/internal.h
+index 8577cab6c83..0ce0246c5a2 100644
+--- a/libcpp/internal.h
++++ b/libcpp/internal.h
+@@ -597,6 +597,13 @@ struct cpp_reader
+ /* Location identifying the main source file -- intended to be line
+ zero of said file. */
+ location_t main_loc;
++
++ /* Returns true iff we should warn about UTF-8 bidirectional control
++ characters. */
++ bool warn_bidi_p () const
++ {
++ return CPP_OPTION (this, cpp_warn_bidirectional) != bidirectional_none;
++ }
+ };
+
+ /* Character classes. Based on the more primitive macros in safe-ctype.h.
+diff --git a/libcpp/lex.c b/libcpp/lex.c
+index fa2253d41c3..6a4fbce6030 100644
+--- a/libcpp/lex.c
++++ b/libcpp/lex.c
+@@ -1164,6 +1164,324 @@ _cpp_process_line_notes (cpp_reader *pfi
+ }
+ }
+
++namespace bidi {
++ enum class kind {
++ NONE, LRE, RLE, LRO, RLO, LRI, RLI, FSI, PDF, PDI, LTR, RTL
++ };
++
++ /* All the UTF-8 encodings of bidi characters start with E2. */
++ constexpr uchar utf8_start = 0xe2;
++
++ /* A vector holding currently open bidi contexts. We use a char for
++ each context, its LSB is 1 if it represents a PDF context, 0 if it
++ represents a PDI context. The next bit is 1 if this context was open
++ by a bidi character written as a UCN, and 0 when it was UTF-8. */
++ semi_embedded_vec <unsigned char, 16> vec;
++
++ /* Close the whole comment/identifier/string literal/character constant
++ context. */
++ void on_close ()
++ {
++ vec.truncate (0);
++ }
++
++ /* Pop the last element in the vector. */
++ void pop ()
++ {
++ unsigned int len = vec.count ();
++ gcc_checking_assert (len > 0);
++ vec.truncate (len - 1);
++ }
++
++ /* Return the context of the Ith element. */
++ kind ctx_at (unsigned int i)
++ {
++ return (vec[i] & 1) ? kind::PDF : kind::PDI;
++ }
++
++ /* Return which context is currently opened. */
++ kind current_ctx ()
++ {
++ unsigned int len = vec.count ();
++ if (len == 0)
++ return kind::NONE;
++ return ctx_at (len - 1);
++ }
++
++ /* Return true if the current context comes from a UCN origin, that is,
++ the bidi char which started this bidi context was written as a UCN. */
++ bool current_ctx_ucn_p ()
++ {
++ unsigned int len = vec.count ();
++ gcc_checking_assert (len > 0);
++ return (vec[len - 1] >> 1) & 1;
++ }
++
++ /* We've read a bidi char, update the current vector as necessary. */
++ void on_char (kind k, bool ucn_p)
++ {
++ switch (k)
++ {
++ case kind::LRE:
++ case kind::RLE:
++ case kind::LRO:
++ case kind::RLO:
++ vec.push (ucn_p ? 3u : 1u);
++ break;
++ case kind::LRI:
++ case kind::RLI:
++ case kind::FSI:
++ vec.push (ucn_p ? 2u : 0u);
++ break;
++ /* PDF terminates the scope of the last LRE, RLE, LRO, or RLO
++ whose scope has not yet been terminated. */
++ case kind::PDF:
++ if (current_ctx () == kind::PDF)
++ pop ();
++ break;
++ /* PDI terminates the scope of the last LRI, RLI, or FSI whose
++ scope has not yet been terminated, as well as the scopes of
++ any subsequent LREs, RLEs, LROs, or RLOs whose scopes have not
++ yet been terminated. */
++ case kind::PDI:
++ for (int i = vec.count () - 1; i >= 0; --i)
++ if (ctx_at (i) == kind::PDI)
++ {
++ vec.truncate (i);
++ break;
++ }
++ break;
++ case kind::LTR:
++ case kind::RTL:
++ /* These aren't popped by a PDF/PDI. */
++ break;
++ [[likely]] case kind::NONE:
++ break;
++ default:
++ abort ();
++ }
++ }
++
++ /* Return a descriptive string for K. */
++ const char *to_str (kind k)
++ {
++ switch (k)
++ {
++ case kind::LRE:
++ return "U+202A (LEFT-TO-RIGHT EMBEDDING)";
++ case kind::RLE:
++ return "U+202B (RIGHT-TO-LEFT EMBEDDING)";
++ case kind::LRO:
++ return "U+202D (LEFT-TO-RIGHT OVERRIDE)";
++ case kind::RLO:
++ return "U+202E (RIGHT-TO-LEFT OVERRIDE)";
++ case kind::LRI:
++ return "U+2066 (LEFT-TO-RIGHT ISOLATE)";
++ case kind::RLI:
++ return "U+2067 (RIGHT-TO-LEFT ISOLATE)";
++ case kind::FSI:
++ return "U+2068 (FIRST STRONG ISOLATE)";
++ case kind::PDF:
++ return "U+202C (POP DIRECTIONAL FORMATTING)";
++ case kind::PDI:
++ return "U+2069 (POP DIRECTIONAL ISOLATE)";
++ case kind::LTR:
++ return "U+200E (LEFT-TO-RIGHT MARK)";
++ case kind::RTL:
++ return "U+200F (RIGHT-TO-LEFT MARK)";
++ default:
++ abort ();
++ }
++ }
++}
++
++/* Parse a sequence of 3 bytes starting with P and return its bidi code. */
++
++static bidi::kind
++get_bidi_utf8 (const unsigned char *const p)
++{
++ gcc_checking_assert (p[0] == bidi::utf8_start);
++
++ if (p[1] == 0x80)
++ switch (p[2])
++ {
++ case 0xaa:
++ return bidi::kind::LRE;
++ case 0xab:
++ return bidi::kind::RLE;
++ case 0xac:
++ return bidi::kind::PDF;
++ case 0xad:
++ return bidi::kind::LRO;
++ case 0xae:
++ return bidi::kind::RLO;
++ case 0x8e:
++ return bidi::kind::LTR;
++ case 0x8f:
++ return bidi::kind::RTL;
++ default:
++ break;
++ }
++ else if (p[1] == 0x81)
++ switch (p[2])
++ {
++ case 0xa6:
++ return bidi::kind::LRI;
++ case 0xa7:
++ return bidi::kind::RLI;
++ case 0xa8:
++ return bidi::kind::FSI;
++ case 0xa9:
++ return bidi::kind::PDI;
++ default:
++ break;
++ }
++
++ return bidi::kind::NONE;
++}
++
++/* Parse a UCN where P points just past \u or \U and return its bidi code. */
++
++static bidi::kind
++get_bidi_ucn (const unsigned char *p, bool is_U)
++{
++ /* 6.4.3 Universal Character Names
++ \u hex-quad
++ \U hex-quad hex-quad
++ where \unnnn means \U0000nnnn. */
++
++ if (is_U)
++ {
++ if (p[0] != '0' || p[1] != '0' || p[2] != '0' || p[3] != '0')
++ return bidi::kind::NONE;
++ /* Skip 4B so we can treat \u and \U the same below. */
++ p += 4;
++ }
++
++ /* All code points we are looking for start with 20xx. */
++ if (p[0] != '2' || p[1] != '0')
++ return bidi::kind::NONE;
++ else if (p[2] == '2')
++ switch (p[3])
++ {
++ case 'a':
++ case 'A':
++ return bidi::kind::LRE;
++ case 'b':
++ case 'B':
++ return bidi::kind::RLE;
++ case 'c':
++ case 'C':
++ return bidi::kind::PDF;
++ case 'd':
++ case 'D':
++ return bidi::kind::LRO;
++ case 'e':
++ case 'E':
++ return bidi::kind::RLO;
++ default:
++ break;
++ }
++ else if (p[2] == '6')
++ switch (p[3])
++ {
++ case '6':
++ return bidi::kind::LRI;
++ case '7':
++ return bidi::kind::RLI;
++ case '8':
++ return bidi::kind::FSI;
++ case '9':
++ return bidi::kind::PDI;
++ default:
++ break;
++ }
++ else if (p[2] == '0')
++ switch (p[3])
++ {
++ case 'e':
++ case 'E':
++ return bidi::kind::LTR;
++ case 'f':
++ case 'F':
++ return bidi::kind::RTL;
++ default:
++ break;
++ }
++
++ return bidi::kind::NONE;
++}
++
++/* We're closing a bidi context, that is, we've encountered a newline,
++ are closing a C-style comment, or are at the end of a string literal,
++ character constant, or identifier. Warn if this context was not
++ properly terminated by a PDI or PDF. P points to the last character
++ in this context. */
++
++static void
++maybe_warn_bidi_on_close (cpp_reader *pfile, const uchar *p)
++{
++ if (CPP_OPTION (pfile, cpp_warn_bidirectional) == bidirectional_unpaired
++ && bidi::vec.count () > 0)
++ {
++ const location_t loc
++ = linemap_position_for_column (pfile->line_table,
++ CPP_BUF_COLUMN (pfile->buffer, p));
++ cpp_warning_with_line (pfile, CPP_W_BIDIRECTIONAL, loc, 0,
++ "unpaired UTF-8 bidirectional control character "
++ "detected");
++ }
++ /* We're done with this context. */
++ bidi::on_close ();
++}
++
++/* We're at the beginning or in the middle of an identifier/comment/string
++ literal/character constant. Warn if we've encountered a bidi character.
++ KIND says which bidi character it was; P points to it in the character
++ stream. UCN_P is true iff this bidi character was written as a UCN. */
++
++static void
++maybe_warn_bidi_on_char (cpp_reader *pfile, const uchar *p, bidi::kind kind,
++ bool ucn_p)
++{
++ if (__builtin_expect (kind == bidi::kind::NONE, 1))
++ return;
++
++ const auto warn_bidi = CPP_OPTION (pfile, cpp_warn_bidirectional);
++
++ if (warn_bidi != bidirectional_none)
++ {
++ const location_t loc
++ = linemap_position_for_column (pfile->line_table,
++ CPP_BUF_COLUMN (pfile->buffer, p));
++ /* It seems excessive to warn about a PDI/PDF that is closing
++ an opened context because we've already warned about the
++ opening character. Except warn when we have a UCN x UTF-8
++ mismatch. */
++ if (kind == bidi::current_ctx ())
++ {
++ if (warn_bidi == bidirectional_unpaired
++ && bidi::current_ctx_ucn_p () != ucn_p)
++ cpp_warning_with_line (pfile, CPP_W_BIDIRECTIONAL, loc, 0,
++ "UTF-8 vs UCN mismatch when closing "
++ "a context by \"%s\"", bidi::to_str (kind));
++ }
++ else if (warn_bidi == bidirectional_any)
++ {
++ if (kind == bidi::kind::PDF || kind == bidi::kind::PDI)
++ cpp_warning_with_line (pfile, CPP_W_BIDIRECTIONAL, loc, 0,
++ "\"%s\" is closing an unopened context",
++ bidi::to_str (kind));
++ else
++ cpp_warning_with_line (pfile, CPP_W_BIDIRECTIONAL, loc, 0,
++ "found problematic Unicode character \"%s\"",
++ bidi::to_str (kind));
++ }
++ }
++ /* We're done with this context. */
++ bidi::on_char (kind, ucn_p);
++}
++
+ /* Skip a C-style block comment. We find the end of the comment by
+ seeing if an asterisk is before every '/' we encounter. Returns
+ nonzero if comment terminated by EOF, zero otherwise.
+@@ -1175,6 +1493,7 @@ _cpp_skip_block_comment (cpp_reader *pfi
+ cpp_buffer *buffer = pfile->buffer;
+ const uchar *cur = buffer->cur;
+ uchar c;
++ const bool warn_bidi_p = pfile->warn_bidi_p ();
+
+ cur++;
+ if (*cur == '/')
+@@ -1189,7 +1508,11 @@ _cpp_skip_block_comment (cpp_reader *pfi
+ if (c == '/')
+ {
+ if (cur[-2] == '*')
+- break;
++ {
++ if (warn_bidi_p)
++ maybe_warn_bidi_on_close (pfile, cur);
++ break;
++ }
+
+ /* Warn about potential nested comments, but not if the '/'
+ comes immediately before the true comment delimiter.
+@@ -1208,6 +1531,8 @@ _cpp_skip_block_comment (cpp_reader *pfi
+ {
+ unsigned int cols;
+ buffer->cur = cur - 1;
++ if (warn_bidi_p)
++ maybe_warn_bidi_on_close (pfile, cur);
+ _cpp_process_line_notes (pfile, true);
+ if (buffer->next_line >= buffer->rlimit)
+ return true;
+@@ -1218,6 +1543,13 @@ _cpp_skip_block_comment (cpp_reader *pfi
+
+ cur = buffer->cur;
+ }
++ /* If this is a beginning of a UTF-8 encoding, it might be
++ a bidirectional control character. */
++ else if (__builtin_expect (c == bidi::utf8_start, 0) && warn_bidi_p)
++ {
++ bidi::kind kind = get_bidi_utf8 (cur - 1);
++ maybe_warn_bidi_on_char (pfile, cur, kind, /*ucn_p=*/false);
++ }
+ }
+
+ buffer->cur = cur;
+@@ -1233,9 +1565,31 @@ skip_line_comment (cpp_reader *pfile)
+ {
+ cpp_buffer *buffer = pfile->buffer;
+ location_t orig_line = pfile->line_table->highest_line;
++ const bool warn_bidi_p = pfile->warn_bidi_p ();
+
+- while (*buffer->cur != '\n')
+- buffer->cur++;
++ if (!warn_bidi_p)
++ while (*buffer->cur != '\n')
++ buffer->cur++;
++ else
++ {
++ while (*buffer->cur != '\n'
++ && *buffer->cur != bidi::utf8_start)
++ buffer->cur++;
++ if (__builtin_expect (*buffer->cur == bidi::utf8_start, 0))
++ {
++ while (*buffer->cur != '\n')
++ {
++ if (__builtin_expect (*buffer->cur == bidi::utf8_start, 0))
++ {
++ bidi::kind kind = get_bidi_utf8 (buffer->cur);
++ maybe_warn_bidi_on_char (pfile, buffer->cur, kind,
++ /*ucn_p=*/false);
++ }
++ buffer->cur++;
++ }
++ maybe_warn_bidi_on_close (pfile, buffer->cur);
++ }
++ }
+
+ _cpp_process_line_notes (pfile, true);
+ return orig_line != pfile->line_table->highest_line;
+@@ -1317,11 +1671,13 @@ static const cppchar_t utf8_signifier =
+
+ /* Returns TRUE if the sequence starting at buffer->cur is valid in
+ an identifier. FIRST is TRUE if this starts an identifier. */
++
+ static bool
+ forms_identifier_p (cpp_reader *pfile, int first,
+ struct normalize_state *state)
+ {
+ cpp_buffer *buffer = pfile->buffer;
++ const bool warn_bidi_p = pfile->warn_bidi_p ();
+
+ if (*buffer->cur == '$')
+ {
+@@ -1344,6 +1700,13 @@ forms_identifier_p (cpp_reader *pfile, i
+ cppchar_t s;
+ if (*buffer->cur >= utf8_signifier)
+ {
++ if (__builtin_expect (*buffer->cur == bidi::utf8_start, 0)
++ && warn_bidi_p)
++ {
++ bidi::kind kind = get_bidi_utf8 (buffer->cur);
++ maybe_warn_bidi_on_char (pfile, buffer->cur, kind,
++ /*ucn_p=*/false);
++ }
+ if (_cpp_valid_utf8 (pfile, &buffer->cur, buffer->rlimit, 1 + !first,
+ state, &s))
+ return true;
+@@ -1352,6 +1715,13 @@ forms_identifier_p (cpp_reader *pfile, i
+ && (buffer->cur[1] == 'u' || buffer->cur[1] == 'U'))
+ {
+ buffer->cur += 2;
++ if (warn_bidi_p)
++ {
++ bidi::kind kind = get_bidi_ucn (buffer->cur,
++ buffer->cur[-1] == 'U');
++ maybe_warn_bidi_on_char (pfile, buffer->cur, kind,
++ /*ucn_p=*/true);
++ }
+ if (_cpp_valid_ucn (pfile, &buffer->cur, buffer->rlimit, 1 + !first,
+ state, &s, NULL, NULL))
+ return true;
+@@ -1460,6 +1830,7 @@ lex_identifier (cpp_reader *pfile, const
+ const uchar *cur;
+ unsigned int len;
+ unsigned int hash = HT_HASHSTEP (0, *base);
++ const bool warn_bidi_p = pfile->warn_bidi_p ();
+
+ cur = pfile->buffer->cur;
+ if (! starts_ucn)
+@@ -1483,6 +1854,8 @@ lex_identifier (cpp_reader *pfile, const
+ pfile->buffer->cur++;
+ }
+ } while (forms_identifier_p (pfile, false, nst));
++ if (warn_bidi_p)
++ maybe_warn_bidi_on_close (pfile, pfile->buffer->cur);
+ result = _cpp_interpret_identifier (pfile, base,
+ pfile->buffer->cur - base);
+ *spelling = cpp_lookup (pfile, base, pfile->buffer->cur - base);
+@@ -1719,6 +2092,7 @@ static void
+ lex_raw_string (cpp_reader *pfile, cpp_token *token, const uchar *base)
+ {
+ const uchar *pos = base;
++ const bool warn_bidi_p = pfile->warn_bidi_p ();
+
+ /* 'tis a pity this information isn't passed down from the lexer's
+ initial categorization of the token. */
+@@ -1955,8 +2329,15 @@ lex_raw_string (cpp_reader *pfile, cpp_t
+ pos = base = pfile->buffer->cur;
+ note = &pfile->buffer->notes[pfile->buffer->cur_note];
+ }
++ else if (__builtin_expect ((unsigned char) c == bidi::utf8_start, 0)
++ && warn_bidi_p)
++ maybe_warn_bidi_on_char (pfile, pos - 1, get_bidi_utf8 (pos - 1),
++ /*ucn_p=*/false);
+ }
+
++ if (warn_bidi_p)
++ maybe_warn_bidi_on_close (pfile, pos);
++
+ if (CPP_OPTION (pfile, user_literals))
+ {
+ /* If a string format macro, say from inttypes.h, is placed touching
+@@ -2051,15 +2432,27 @@ lex_string (cpp_reader *pfile, cpp_token
+ else
+ terminator = '>', type = CPP_HEADER_NAME;
+
++ const bool warn_bidi_p = pfile->warn_bidi_p ();
+ for (;;)
+ {
+ cppchar_t c = *cur++;
+
+ /* In #include-style directives, terminators are not escapable. */
+ if (c == '\\' && !pfile->state.angled_headers && *cur != '\n')
+- cur++;
++ {
++ if ((cur[0] == 'u' || cur[0] == 'U') && warn_bidi_p)
++ {
++ bidi::kind kind = get_bidi_ucn (cur + 1, cur[0] == 'U');
++ maybe_warn_bidi_on_char (pfile, cur, kind, /*ucn_p=*/true);
++ }
++ cur++;
++ }
+ else if (c == terminator)
+- break;
++ {
++ if (warn_bidi_p)
++ maybe_warn_bidi_on_close (pfile, cur - 1);
++ break;
++ }
+ else if (c == '\n')
+ {
+ cur--;
+@@ -2076,6 +2469,11 @@ lex_string (cpp_reader *pfile, cpp_token
+ }
+ else if (c == '\0')
+ saw_NUL = true;
++ else if (__builtin_expect (c == bidi::utf8_start, 0) && warn_bidi_p)
++ {
++ bidi::kind kind = get_bidi_utf8 (cur - 1);
++ maybe_warn_bidi_on_char (pfile, cur - 1, kind, /*ucn_p=*/false);
++ }
+ }
+
+ if (saw_NUL && !pfile->state.skipping)
diff --git a/meta/recipes-devtools/gcc/gcc/0003-CVE-2021-42574.patch b/meta/recipes-devtools/gcc/gcc/0003-CVE-2021-42574.patch
new file mode 100644
index 0000000000..2995a6fc61
--- /dev/null
+++ b/meta/recipes-devtools/gcc/gcc/0003-CVE-2021-42574.patch
@@ -0,0 +1,142 @@
+From 1a7f2c0774129750fdf73e9f1b78f0ce983c9ab3 Mon Sep 17 00:00:00 2001
+From: David Malcolm <dmalcolm@redhat.com>
+Date: Tue, 2 Nov 2021 09:54:32 -0400
+Subject: [PATCH] libcpp: escape non-ASCII source bytes in -Wbidi-chars=
+ [PR103026]
+MIME-Version: 1.0
+Content-Type: text/plain; charset=utf8
+Content-Transfer-Encoding: 8bit
+
+This flags rich_locations associated with -Wbidi-chars= so that
+non-ASCII bytes will be escaped when printing the source lines
+(using the diagnostics support I added in
+r12-4825-gbd5e882cf6e0def3dd1bc106075d59a303fe0d1e).
+
+In particular, this ensures that the printed source lines will
+be pure ASCII, and thus the visual ordering of the characters
+will be the same as the logical ordering.
+
+Before:
+
+ Wbidi-chars-1.c: In function âmainâ:
+ Wbidi-chars-1.c:6:43: warning: unpaired UTF-8 bidirectional control character detected [-Wbidi-chars=]
+ 6 | /*â® } â¦if (isAdmin)⩠⦠begin admins only */
+ | ^
+ Wbidi-chars-1.c:9:28: warning: unpaired UTF-8 bidirectional control character detected [-Wbidi-chars=]
+ 9 | /* end admins only â® { â¦*/
+ | ^
+
+ Wbidi-chars-11.c:6:15: warning: UTF-8 vs UCN mismatch when closing a context by "U+202C (POP DIRECTIONAL FORMATTING)" [-Wbidi-chars=]
+ 6 | int LRE_âª_PDF_\u202c;
+ | ^
+ Wbidi-chars-11.c:8:19: warning: UTF-8 vs UCN mismatch when closing a context by "U+202C (POP DIRECTIONAL FORMATTING)" [-Wbidi-chars=]
+ 8 | int LRE_\u202a_PDF_â¬_;
+ | ^
+ Wbidi-chars-11.c:10:28: warning: UTF-8 vs UCN mismatch when closing a context by "U+202C (POP DIRECTIONAL FORMATTING)" [-Wbidi-chars=]
+ 10 | const char *s1 = "LRE_âª_PDF_\u202c";
+ | ^
+ Wbidi-chars-11.c:12:33: warning: UTF-8 vs UCN mismatch when closing a context by "U+202C (POP DIRECTIONAL FORMATTING)" [-Wbidi-chars=]
+ 12 | const char *s2 = "LRE_\u202a_PDF_â¬";
+ | ^
+
+After:
+
+ Wbidi-chars-1.c: In function âmainâ:
+ Wbidi-chars-1.c:6:43: warning: unpaired UTF-8 bidirectional control character detected [-Wbidi-chars=]
+ 6 | /*<U+202E> } <U+2066>if (isAdmin)<U+2069> <U+2066> begin admins only */
+ | ^
+ Wbidi-chars-1.c:9:28: warning: unpaired UTF-8 bidirectional control character detected [-Wbidi-chars=]
+ 9 | /* end admins only <U+202E> { <U+2066>*/
+ | ^
+
+ Wbidi-chars-11.c:6:15: warning: UTF-8 vs UCN mismatch when closing a context by "U+202C (POP DIRECTIONAL FORMATTING)" [-Wbidi-chars=]
+ 6 | int LRE_<U+202A>_PDF_\u202c;
+ | ^
+ Wbidi-chars-11.c:8:19: warning: UTF-8 vs UCN mismatch when closing a context by "U+202C (POP DIRECTIONAL FORMATTING)" [-Wbidi-chars=]
+ 8 | int LRE_\u202a_PDF_<U+202C>_;
+ | ^
+ Wbidi-chars-11.c:10:28: warning: UTF-8 vs UCN mismatch when closing a context by "U+202C (POP DIRECTIONAL FORMATTING)" [-Wbidi-chars=]
+ 10 | const char *s1 = "LRE_<U+202A>_PDF_\u202c";
+ | ^
+ Wbidi-chars-11.c:12:33: warning: UTF-8 vs UCN mismatch when closing a context by "U+202C (POP DIRECTIONAL FORMATTING)" [-Wbidi-chars=]
+ 12 | const char *s2 = "LRE_\u202a_PDF_<U+202C>";
+ | ^
+
+libcpp/ChangeLog:
+ PR preprocessor/103026
+ * lex.c (maybe_warn_bidi_on_close): Use a rich_location
+ and call set_escape_on_output (true) on it.
+ (maybe_warn_bidi_on_char): Likewise.
+
+Signed-off-by: David Malcolm <dmalcolm@redhat.com>
+
+CVE: CVE-2021-42574
+Upstream-Status: Backport [https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=1a7f2c0774129750fdf73e9f1b78f0ce983c9ab3]
+Signed-off-by: Pgowda <pgowda.cve@gmail.com>
+
+---
+ libcpp/lex.c | 29 +++++++++++++++++------------
+ 1 file changed, 17 insertions(+), 12 deletions(-)
+
+diff --git a/libcpp/lex.c b/libcpp/lex.c
+index 8188e33b07d..2421d6c0f40 100644
+--- a/libcpp/lex.c
++++ b/libcpp/lex.c
+@@ -1427,9 +1427,11 @@ maybe_warn_bidi_on_close (cpp_reader *pfile, const uchar *p)
+ const location_t loc
+ = linemap_position_for_column (pfile->line_table,
+ CPP_BUF_COLUMN (pfile->buffer, p));
+- cpp_warning_with_line (pfile, CPP_W_BIDIRECTIONAL, loc, 0,
+- "unpaired UTF-8 bidirectional control character "
+- "detected");
++ rich_location rich_loc (pfile->line_table, loc);
++ rich_loc.set_escape_on_output (true);
++ cpp_warning_at (pfile, CPP_W_BIDIRECTIONAL, &rich_loc,
++ "unpaired UTF-8 bidirectional control character "
++ "detected");
+ }
+ /* We're done with this context. */
+ bidi::on_close ();
+@@ -1454,6 +1456,9 @@ maybe_warn_bidi_on_char (cpp_reader *pfile, const uchar *p, bidi::kind kind,
+ const location_t loc
+ = linemap_position_for_column (pfile->line_table,
+ CPP_BUF_COLUMN (pfile->buffer, p));
++ rich_location rich_loc (pfile->line_table, loc);
++ rich_loc.set_escape_on_output (true);
++
+ /* It seems excessive to warn about a PDI/PDF that is closing
+ an opened context because we've already warned about the
+ opening character. Except warn when we have a UCN x UTF-8
+@@ -1462,20 +1467,20 @@ maybe_warn_bidi_on_char (cpp_reader *pfile, const uchar *p, bidi::kind kind,
+ {
+ if (warn_bidi == bidirectional_unpaired
+ && bidi::current_ctx_ucn_p () != ucn_p)
+- cpp_warning_with_line (pfile, CPP_W_BIDIRECTIONAL, loc, 0,
+- "UTF-8 vs UCN mismatch when closing "
+- "a context by \"%s\"", bidi::to_str (kind));
++ cpp_warning_at (pfile, CPP_W_BIDIRECTIONAL, &rich_loc,
++ "UTF-8 vs UCN mismatch when closing "
++ "a context by \"%s\"", bidi::to_str (kind));
+ }
+ else if (warn_bidi == bidirectional_any)
+ {
+ if (kind == bidi::kind::PDF || kind == bidi::kind::PDI)
+- cpp_warning_with_line (pfile, CPP_W_BIDIRECTIONAL, loc, 0,
+- "\"%s\" is closing an unopened context",
+- bidi::to_str (kind));
++ cpp_warning_at (pfile, CPP_W_BIDIRECTIONAL, &rich_loc,
++ "\"%s\" is closing an unopened context",
++ bidi::to_str (kind));
+ else
+- cpp_warning_with_line (pfile, CPP_W_BIDIRECTIONAL, loc, 0,
+- "found problematic Unicode character \"%s\"",
+- bidi::to_str (kind));
++ cpp_warning_at (pfile, CPP_W_BIDIRECTIONAL, &rich_loc,
++ "found problematic Unicode character \"%s\"",
++ bidi::to_str (kind));
+ }
+ }
+ /* We're done with this context. */
+--
+2.27.0
+
diff --git a/meta/recipes-devtools/gcc/gcc/0004-CVE-2021-42574.patch b/meta/recipes-devtools/gcc/gcc/0004-CVE-2021-42574.patch
new file mode 100644
index 0000000000..4999c71b64
--- /dev/null
+++ b/meta/recipes-devtools/gcc/gcc/0004-CVE-2021-42574.patch
@@ -0,0 +1,573 @@
+From bef32d4a28595e933f24fef378cf052a30b674a7 Mon Sep 17 00:00:00 2001
+From: David Malcolm <dmalcolm@redhat.com>
+Date: Tue, 2 Nov 2021 15:45:22 -0400
+Subject: [PATCH] libcpp: capture and underline ranges in -Wbidi-chars=
+ [PR103026]
+MIME-Version: 1.0
+Content-Type: text/plain; charset=utf8
+Content-Transfer-Encoding: 8bit
+
+This patch converts the bidi::vec to use a struct so that we can
+capture location_t values for the bidirectional control characters.
+
+Before:
+
+ Wbidi-chars-1.c: In function âmainâ:
+ Wbidi-chars-1.c:6:43: warning: unpaired UTF-8 bidirectional control character detected [-Wbidi-chars=]
+ 6 | /*<U+202E> } <U+2066>if (isAdmin)<U+2069> <U+2066> begin admins only */
+ | ^
+ Wbidi-chars-1.c:9:28: warning: unpaired UTF-8 bidirectional control character detected [-Wbidi-chars=]
+ 9 | /* end admins only <U+202E> { <U+2066>*/
+ | ^
+
+After:
+
+ Wbidi-chars-1.c: In function âmainâ:
+ Wbidi-chars-1.c:6:43: warning: unpaired UTF-8 bidirectional control characters detected [-Wbidi-chars=]
+ 6 | /*<U+202E> } <U+2066>if (isAdmin)<U+2069> <U+2066> begin admins only */
+ | ~~~~~~~~ ~~~~~~~~ ^
+ | | | |
+ | | | end of bidirectional context
+ | U+202E (RIGHT-TO-LEFT OVERRIDE) U+2066 (LEFT-TO-RIGHT ISOLATE)
+ Wbidi-chars-1.c:9:28: warning: unpaired UTF-8 bidirectional control characters detected [-Wbidi-chars=]
+ 9 | /* end admins only <U+202E> { <U+2066>*/
+ | ~~~~~~~~ ~~~~~~~~ ^
+ | | | |
+ | | | end of bidirectional context
+ | | U+2066 (LEFT-TO-RIGHT ISOLATE)
+ | U+202E (RIGHT-TO-LEFT OVERRIDE)
+
+Signed-off-by: David Malcolm <dmalcolm@redhat.com>
+
+gcc/testsuite/ChangeLog:
+ PR preprocessor/103026
+ * c-c++-common/Wbidi-chars-ranges.c: New test.
+
+libcpp/ChangeLog:
+ PR preprocessor/103026
+ * lex.c (struct bidi::context): New.
+ (bidi::vec): Convert to a vec of context rather than unsigned
+ char.
+ (bidi::ctx_at): Rename to...
+ (bidi::pop_kind_at): ...this and reimplement for above change.
+ (bidi::current_ctx): Update for change to vec.
+ (bidi::current_ctx_ucn_p): Likewise.
+ (bidi::current_ctx_loc): New.
+ (bidi::on_char): Update for usage of context struct. Add "loc"
+ param and pass it when pushing contexts.
+ (get_location_for_byte_range_in_cur_line): New.
+ (get_bidi_utf8): Rename to...
+ (get_bidi_utf8_1): ...this, reintroducing...
+ (get_bidi_utf8): ...as a wrapper, setting *OUT when the result is
+ not NONE.
+ (get_bidi_ucn): Rename to...
+ (get_bidi_ucn_1): ...this, reintroducing...
+ (get_bidi_ucn): ...as a wrapper, setting *OUT when the result is
+ not NONE.
+ (class unpaired_bidi_rich_location): New.
+ (maybe_warn_bidi_on_close): Use unpaired_bidi_rich_location when
+ reporting on unpaired bidi chars. Split into singular vs plural
+ spellings.
+ (maybe_warn_bidi_on_char): Pass in a location_t rather than a
+ const uchar * and use it when emitting warnings, and when calling
+ bidi::on_char.
+ (_cpp_skip_block_comment): Capture location when kind is not NONE
+ and pass it to maybe_warn_bidi_on_char.
+ (skip_line_comment): Likewise.
+ (forms_identifier_p): Likewise.
+ (lex_raw_string): Likewise.
+ (lex_string): Likewise.
+
+Signed-off-by: David Malcolm <dmalcolm@redhat.com>
+
+CVE: CVE-2021-42574
+Upstream-Status: Backport [https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=bef32d4a28595e933f24fef378cf052a30b674a7]
+Signed-off-by: Pgowda <pgowda.cve@gmail.com>
+
+---
+ .../c-c++-common/Wbidi-chars-ranges.c | 54 ++++
+ libcpp/lex.c | 251 ++++++++++++++----
+ 2 files changed, 257 insertions(+), 48 deletions(-)
+ create mode 100644 gcc/testsuite/c-c++-common/Wbidi-chars-ranges.c
+
+diff --git a/gcc/testsuite/c-c++-common/Wbidi-chars-ranges.c b/gcc/testsuite/c-c++-common/Wbidi-chars-ranges.c
+new file mode 100644
+index 00000000000..298750a2a64
+--- /dev/null
++++ b/gcc/testsuite/c-c++-common/Wbidi-chars-ranges.c
+@@ -0,0 +1,54 @@
++/* PR preprocessor/103026 */
++/* { dg-do compile } */
++/* { dg-options "-Wbidi-chars=unpaired -fdiagnostics-show-caret" } */
++/* Verify that we escape and underline pertinent bidirectional
++ control characters when quoting the source. */
++
++int test_unpaired_bidi () {
++ int isAdmin = 0;
++ /*â® } â¦if (isAdmin)⩠⦠begin admins only */
++/* { dg-warning "bidirectional" "" { target *-*-* } .-1 } */
++#if 0
++ { dg-begin-multiline-output "" }
++ /*<U+202E> } <U+2066>if (isAdmin)<U+2069> <U+2066> begin admins only */
++ ~~~~~~~~ ~~~~~~~~ ^
++ | | |
++ | | end of bidirectional context
++ U+202E (RIGHT-TO-LEFT OVERRIDE) U+2066 (LEFT-TO-RIGHT ISOLATE)
++ { dg-end-multiline-output "" }
++#endif
++
++ __builtin_printf("You are an admin.\n");
++ /* end admins only â® { â¦*/
++/* { dg-warning "bidirectional" "" { target *-*-* } .-1 } */
++#if 0
++ { dg-begin-multiline-output "" }
++ /* end admins only <U+202E> { <U+2066>*/
++ ~~~~~~~~ ~~~~~~~~ ^
++ | | |
++ | | end of bidirectional context
++ | U+2066 (LEFT-TO-RIGHT ISOLATE)
++ U+202E (RIGHT-TO-LEFT OVERRIDE)
++ { dg-end-multiline-output "" }
++#endif
++
++ return 0;
++}
++
++int LRE_âª_PDF_\u202c;
++/* { dg-warning "mismatch" "" { target *-*-* } .-1 } */
++#if 0
++ { dg-begin-multiline-output "" }
++ int LRE_<U+202A>_PDF_\u202c;
++ ~~~~~~~~ ^~~~~~
++ { dg-end-multiline-output "" }
++#endif
++
++const char *s1 = "LRE_âª_PDF_\u202c";
++/* { dg-warning "mismatch" "" { target *-*-* } .-1 } */
++#if 0
++ { dg-begin-multiline-output "" }
++ const char *s1 = "LRE_<U+202A>_PDF_\u202c";
++ ~~~~~~~~ ^~~~~~
++ { dg-end-multiline-output "" }
++#endif
+diff --git a/libcpp/lex.c b/libcpp/lex.c
+index 2421d6c0f40..94c36f0d014 100644
+--- a/libcpp/lex.c
++++ b/libcpp/lex.c
+@@ -1172,11 +1172,34 @@ namespace bidi {
+ /* All the UTF-8 encodings of bidi characters start with E2. */
+ constexpr uchar utf8_start = 0xe2;
+
++ struct context
++ {
++ context () {}
++ context (location_t loc, kind k, bool pdf, bool ucn)
++ : m_loc (loc), m_kind (k), m_pdf (pdf), m_ucn (ucn)
++ {
++ }
++
++ kind get_pop_kind () const
++ {
++ return m_pdf ? kind::PDF : kind::PDI;
++ }
++ bool ucn_p () const
++ {
++ return m_ucn;
++ }
++
++ location_t m_loc;
++ kind m_kind;
++ unsigned m_pdf : 1;
++ unsigned m_ucn : 1;
++ };
++
+ /* A vector holding currently open bidi contexts. We use a char for
+ each context, its LSB is 1 if it represents a PDF context, 0 if it
+ represents a PDI context. The next bit is 1 if this context was open
+ by a bidi character written as a UCN, and 0 when it was UTF-8. */
+- semi_embedded_vec <unsigned char, 16> vec;
++ semi_embedded_vec <context, 16> vec;
+
+ /* Close the whole comment/identifier/string literal/character constant
+ context. */
+@@ -1193,19 +1216,19 @@ namespace bidi {
+ vec.truncate (len - 1);
+ }
+
+- /* Return the context of the Ith element. */
+- kind ctx_at (unsigned int i)
++ /* Return the pop kind of the context of the Ith element. */
++ kind pop_kind_at (unsigned int i)
+ {
+- return (vec[i] & 1) ? kind::PDF : kind::PDI;
++ return vec[i].get_pop_kind ();
+ }
+
+- /* Return which context is currently opened. */
++ /* Return the pop kind of the context that is currently opened. */
+ kind current_ctx ()
+ {
+ unsigned int len = vec.count ();
+ if (len == 0)
+ return kind::NONE;
+- return ctx_at (len - 1);
++ return vec[len - 1].get_pop_kind ();
+ }
+
+ /* Return true if the current context comes from a UCN origin, that is,
+@@ -1214,11 +1237,19 @@ namespace bidi {
+ {
+ unsigned int len = vec.count ();
+ gcc_checking_assert (len > 0);
+- return (vec[len - 1] >> 1) & 1;
++ return vec[len - 1].m_ucn;
+ }
+
+- /* We've read a bidi char, update the current vector as necessary. */
+- void on_char (kind k, bool ucn_p)
++ location_t current_ctx_loc ()
++ {
++ unsigned int len = vec.count ();
++ gcc_checking_assert (len > 0);
++ return vec[len - 1].m_loc;
++ }
++
++ /* We've read a bidi char, update the current vector as necessary.
++ LOC is only valid when K is not kind::NONE. */
++ void on_char (kind k, bool ucn_p, location_t loc)
+ {
+ switch (k)
+ {
+@@ -1226,12 +1257,12 @@ namespace bidi {
+ case kind::RLE:
+ case kind::LRO:
+ case kind::RLO:
+- vec.push (ucn_p ? 3u : 1u);
++ vec.push (context (loc, k, true, ucn_p));
+ break;
+ case kind::LRI:
+ case kind::RLI:
+ case kind::FSI:
+- vec.push (ucn_p ? 2u : 0u);
++ vec.push (context (loc, k, false, ucn_p));
+ break;
+ /* PDF terminates the scope of the last LRE, RLE, LRO, or RLO
+ whose scope has not yet been terminated. */
+@@ -1245,7 +1276,7 @@ namespace bidi {
+ yet been terminated. */
+ case kind::PDI:
+ for (int i = vec.count () - 1; i >= 0; --i)
+- if (ctx_at (i) == kind::PDI)
++ if (pop_kind_at (i) == kind::PDI)
+ {
+ vec.truncate (i);
+ break;
+@@ -1295,10 +1326,47 @@ namespace bidi {
+ }
+ }
+
++/* Get location_t for the range of bytes [START, START + NUM_BYTES)
++ within the current line in FILE, with the caret at START. */
++
++static location_t
++get_location_for_byte_range_in_cur_line (cpp_reader *pfile,
++ const unsigned char *const start,
++ size_t num_bytes)
++{
++ gcc_checking_assert (num_bytes > 0);
++
++ /* CPP_BUF_COLUMN and linemap_position_for_column both refer
++ to offsets in bytes, but CPP_BUF_COLUMN is 0-based,
++ whereas linemap_position_for_column is 1-based. */
++
++ /* Get 0-based offsets within the line. */
++ size_t start_offset = CPP_BUF_COLUMN (pfile->buffer, start);
++ size_t end_offset = start_offset + num_bytes - 1;
++
++ /* Now convert to location_t, where "columns" are 1-based byte offsets. */
++ location_t start_loc = linemap_position_for_column (pfile->line_table,
++ start_offset + 1);
++ location_t end_loc = linemap_position_for_column (pfile->line_table,
++ end_offset + 1);
++
++ if (start_loc == end_loc)
++ return start_loc;
++
++ source_range src_range;
++ src_range.m_start = start_loc;
++ src_range.m_finish = end_loc;
++ location_t combined_loc = COMBINE_LOCATION_DATA (pfile->line_table,
++ start_loc,
++ src_range,
++ NULL);
++ return combined_loc;
++}
++
+ /* Parse a sequence of 3 bytes starting with P and return its bidi code. */
+
+ static bidi::kind
+-get_bidi_utf8 (const unsigned char *const p)
++get_bidi_utf8_1 (const unsigned char *const p)
+ {
+ gcc_checking_assert (p[0] == bidi::utf8_start);
+
+@@ -1340,10 +1408,25 @@ get_bidi_utf8 (const unsigned char *cons
+ return bidi::kind::NONE;
+ }
+
++/* Parse a sequence of 3 bytes starting with P and return its bidi code.
++ If the kind is not NONE, write the location to *OUT.*/
++
++static bidi::kind
++get_bidi_utf8 (cpp_reader *pfile, const unsigned char *const p, location_t *out)
++{
++ bidi::kind result = get_bidi_utf8_1 (p);
++ if (result != bidi::kind::NONE)
++ {
++ /* We have a sequence of 3 bytes starting at P. */
++ *out = get_location_for_byte_range_in_cur_line (pfile, p, 3);
++ }
++ return result;
++}
++
+ /* Parse a UCN where P points just past \u or \U and return its bidi code. */
+
+ static bidi::kind
+-get_bidi_ucn (const unsigned char *p, bool is_U)
++get_bidi_ucn_1 (const unsigned char *p, bool is_U)
+ {
+ /* 6.4.3 Universal Character Names
+ \u hex-quad
+@@ -1412,6 +1495,62 @@ get_bidi_ucn (const unsigned char *p, bo
+ return bidi::kind::NONE;
+ }
+
++/* Parse a UCN where P points just past \u or \U and return its bidi code.
++ If the kind is not NONE, write the location to *OUT.*/
++
++static bidi::kind
++get_bidi_ucn (cpp_reader *pfile, const unsigned char *p, bool is_U,
++ location_t *out)
++{
++ bidi::kind result = get_bidi_ucn_1 (p, is_U);
++ if (result != bidi::kind::NONE)
++ {
++ const unsigned char *start = p - 2;
++ size_t num_bytes = 2 + (is_U ? 8 : 4);
++ *out = get_location_for_byte_range_in_cur_line (pfile, start, num_bytes);
++ }
++ return result;
++}
++
++/* Subclass of rich_location for reporting on unpaired UTF-8
++ bidirectional control character(s).
++ Escape the source lines on output, and show all unclosed
++ bidi context, labelling everything. */
++
++class unpaired_bidi_rich_location : public rich_location
++{
++ public:
++ class custom_range_label : public range_label
++ {
++ public:
++ label_text get_text (unsigned range_idx) const FINAL OVERRIDE
++ {
++ /* range 0 is the primary location; each subsequent range i + 1
++ is for bidi::vec[i]. */
++ if (range_idx > 0)
++ {
++ const bidi::context &ctxt (bidi::vec[range_idx - 1]);
++ return label_text::borrow (bidi::to_str (ctxt.m_kind));
++ }
++ else
++ return label_text::borrow (_("end of bidirectional context"));
++ }
++ };
++
++ unpaired_bidi_rich_location (cpp_reader *pfile, location_t loc)
++ : rich_location (pfile->line_table, loc, &m_custom_label)
++ {
++ set_escape_on_output (true);
++ for (unsigned i = 0; i < bidi::vec.count (); i++)
++ add_range (bidi::vec[i].m_loc,
++ SHOW_RANGE_WITHOUT_CARET,
++ &m_custom_label);
++ }
++
++ private:
++ custom_range_label m_custom_label;
++};
++
+ /* We're closing a bidi context, that is, we've encountered a newline,
+ are closing a C-style comment, or are at the end of a string literal,
+ character constant, or identifier. Warn if this context was not
+@@ -1427,11 +1566,17 @@ maybe_warn_bidi_on_close (cpp_reader *pf
+ const location_t loc
+ = linemap_position_for_column (pfile->line_table,
+ CPP_BUF_COLUMN (pfile->buffer, p));
+- rich_location rich_loc (pfile->line_table, loc);
+- rich_loc.set_escape_on_output (true);
+- cpp_warning_at (pfile, CPP_W_BIDIRECTIONAL, &rich_loc,
+- "unpaired UTF-8 bidirectional control character "
+- "detected");
++ unpaired_bidi_rich_location rich_loc (pfile, loc);
++ /* cpp_callbacks doesn't yet have a way to handle singular vs plural
++ forms of a diagnostic, so fake it for now. */
++ if (bidi::vec.count () > 1)
++ cpp_warning_at (pfile, CPP_W_BIDIRECTIONAL, &rich_loc,
++ "unpaired UTF-8 bidirectional control characters "
++ "detected");
++ else
++ cpp_warning_at (pfile, CPP_W_BIDIRECTIONAL, &rich_loc,
++ "unpaired UTF-8 bidirectional control character "
++ "detected");
+ }
+ /* We're done with this context. */
+ bidi::on_close ();
+@@ -1439,12 +1584,13 @@ maybe_warn_bidi_on_close (cpp_reader *pf
+
+ /* We're at the beginning or in the middle of an identifier/comment/string
+ literal/character constant. Warn if we've encountered a bidi character.
+- KIND says which bidi character it was; P points to it in the character
+- stream. UCN_P is true iff this bidi character was written as a UCN. */
++ KIND says which bidi control character it was; UCN_P is true iff this bidi
++ control character was written as a UCN. LOC is the location of the
++ character, but is only valid if KIND != bidi::kind::NONE. */
+
+ static void
+-maybe_warn_bidi_on_char (cpp_reader *pfile, const uchar *p, bidi::kind kind,
+- bool ucn_p)
++maybe_warn_bidi_on_char (cpp_reader *pfile, bidi::kind kind,
++ bool ucn_p, location_t loc)
+ {
+ if (__builtin_expect (kind == bidi::kind::NONE, 1))
+ return;
+@@ -1453,9 +1599,6 @@ maybe_warn_bidi_on_char (cpp_reader *pfi
+
+ if (warn_bidi != bidirectional_none)
+ {
+- const location_t loc
+- = linemap_position_for_column (pfile->line_table,
+- CPP_BUF_COLUMN (pfile->buffer, p));
+ rich_location rich_loc (pfile->line_table, loc);
+ rich_loc.set_escape_on_output (true);
+
+@@ -1467,9 +1610,12 @@ maybe_warn_bidi_on_char (cpp_reader *pfi
+ {
+ if (warn_bidi == bidirectional_unpaired
+ && bidi::current_ctx_ucn_p () != ucn_p)
+- cpp_warning_at (pfile, CPP_W_BIDIRECTIONAL, &rich_loc,
+- "UTF-8 vs UCN mismatch when closing "
+- "a context by \"%s\"", bidi::to_str (kind));
++ {
++ rich_loc.add_range (bidi::current_ctx_loc ());
++ cpp_warning_at (pfile, CPP_W_BIDIRECTIONAL, &rich_loc,
++ "UTF-8 vs UCN mismatch when closing "
++ "a context by \"%s\"", bidi::to_str (kind));
++ }
+ }
+ else if (warn_bidi == bidirectional_any)
+ {
+@@ -1484,7 +1630,7 @@ maybe_warn_bidi_on_char (cpp_reader *pfi
+ }
+ }
+ /* We're done with this context. */
+- bidi::on_char (kind, ucn_p);
++ bidi::on_char (kind, ucn_p, loc);
+ }
+
+ /* Skip a C-style block comment. We find the end of the comment by
+@@ -1552,8 +1698,9 @@ _cpp_skip_block_comment (cpp_reader *pfi
+ a bidirectional control character. */
+ else if (__builtin_expect (c == bidi::utf8_start, 0) && warn_bidi_p)
+ {
+- bidi::kind kind = get_bidi_utf8 (cur - 1);
+- maybe_warn_bidi_on_char (pfile, cur, kind, /*ucn_p=*/false);
++ location_t loc;
++ bidi::kind kind = get_bidi_utf8 (pfile, cur - 1, &loc);
++ maybe_warn_bidi_on_char (pfile, kind, /*ucn_p=*/false, loc);
+ }
+ }
+
+@@ -1586,9 +1733,9 @@ skip_line_comment (cpp_reader *pfile)
+ {
+ if (__builtin_expect (*buffer->cur == bidi::utf8_start, 0))
+ {
+- bidi::kind kind = get_bidi_utf8 (buffer->cur);
+- maybe_warn_bidi_on_char (pfile, buffer->cur, kind,
+- /*ucn_p=*/false);
++ location_t loc;
++ bidi::kind kind = get_bidi_utf8 (pfile, buffer->cur, &loc);
++ maybe_warn_bidi_on_char (pfile, kind, /*ucn_p=*/false, loc);
+ }
+ buffer->cur++;
+ }
+@@ -1708,9 +1855,9 @@ forms_identifier_p (cpp_reader *pfile, i
+ if (__builtin_expect (*buffer->cur == bidi::utf8_start, 0)
+ && warn_bidi_p)
+ {
+- bidi::kind kind = get_bidi_utf8 (buffer->cur);
+- maybe_warn_bidi_on_char (pfile, buffer->cur, kind,
+- /*ucn_p=*/false);
++ location_t loc;
++ bidi::kind kind = get_bidi_utf8 (pfile, buffer->cur, &loc);
++ maybe_warn_bidi_on_char (pfile, kind, /*ucn_p=*/false, loc);
+ }
+ if (_cpp_valid_utf8 (pfile, &buffer->cur, buffer->rlimit, 1 + !first,
+ state, &s))
+@@ -1722,10 +1869,12 @@ forms_identifier_p (cpp_reader *pfile, i
+ buffer->cur += 2;
+ if (warn_bidi_p)
+ {
+- bidi::kind kind = get_bidi_ucn (buffer->cur,
+- buffer->cur[-1] == 'U');
+- maybe_warn_bidi_on_char (pfile, buffer->cur, kind,
+- /*ucn_p=*/true);
++ location_t loc;
++ bidi::kind kind = get_bidi_ucn (pfile,
++ buffer->cur,
++ buffer->cur[-1] == 'U',
++ &loc);
++ maybe_warn_bidi_on_char (pfile, kind, /*ucn_p=*/true, loc);
+ }
+ if (_cpp_valid_ucn (pfile, &buffer->cur, buffer->rlimit, 1 + !first,
+ state, &s, NULL, NULL))
+@@ -2336,8 +2485,11 @@ lex_raw_string (cpp_reader *pfile, cpp_t
+ }
+ else if (__builtin_expect ((unsigned char) c == bidi::utf8_start, 0)
+ && warn_bidi_p)
+- maybe_warn_bidi_on_char (pfile, pos - 1, get_bidi_utf8 (pos - 1),
+- /*ucn_p=*/false);
++ {
++ location_t loc;
++ bidi::kind kind = get_bidi_utf8 (pfile, pos - 1, &loc);
++ maybe_warn_bidi_on_char (pfile, kind, /*ucn_p=*/false, loc);
++ }
+ }
+
+ if (warn_bidi_p)
+@@ -2447,8 +2599,10 @@ lex_string (cpp_reader *pfile, cpp_token
+ {
+ if ((cur[0] == 'u' || cur[0] == 'U') && warn_bidi_p)
+ {
+- bidi::kind kind = get_bidi_ucn (cur + 1, cur[0] == 'U');
+- maybe_warn_bidi_on_char (pfile, cur, kind, /*ucn_p=*/true);
++ location_t loc;
++ bidi::kind kind = get_bidi_ucn (pfile, cur + 1, cur[0] == 'U',
++ &loc);
++ maybe_warn_bidi_on_char (pfile, kind, /*ucn_p=*/true, loc);
+ }
+ cur++;
+ }
+@@ -2476,8 +2630,9 @@ lex_string (cpp_reader *pfile, cpp_token
+ saw_NUL = true;
+ else if (__builtin_expect (c == bidi::utf8_start, 0) && warn_bidi_p)
+ {
+- bidi::kind kind = get_bidi_utf8 (cur - 1);
+- maybe_warn_bidi_on_char (pfile, cur - 1, kind, /*ucn_p=*/false);
++ location_t loc;
++ bidi::kind kind = get_bidi_utf8 (pfile, cur - 1, &loc);
++ maybe_warn_bidi_on_char (pfile, kind, /*ucn_p=*/false, loc);
+ }
+ }
+
--
2.31.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [OE-core] [PATCH] gcc: Fix CVE-2021-42574
2021-12-14 10:46 [PATCH] gcc: Fix CVE-2021-42574 Pgowda
@ 2021-12-14 17:31 ` Randy MacLeod
2021-12-14 17:57 ` Khem Raj
0 siblings, 1 reply; 4+ messages in thread
From: Randy MacLeod @ 2021-12-14 17:31 UTC (permalink / raw)
To: Pgowda, openembedded-core, Khem Raj, Mittal, Anuj, steve
Cc: richard.purdie, rwmacleod, umesh.kalappa0
On 2021-12-14 5:46 a.m., Pgowda wrote:
> Upstream-Status: Backport [https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=bd5e882cf6e0def3dd1bc106075d59a303fe0d1e]
> Upstream-Status: Backport [https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=51c500269bf53749b107807d84271385fad35628]
> Upstream-Status: Backport [https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=1a7f2c0774129750fdf73e9f1b78f0ce983c9ab3]
> Upstream-Status: Backport [https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=bef32d4a28595e933f24fef378cf052a30b674a7]
Ugh, that's quite a bit of patch to fix this bi-directional Unicode
input attack.
I'm fine with these changes though.
I do wonder about how or if we should fix the CVE in older releases.
For example, has or is there an indication that gcc upstream will,
be backporting these patches to:
$ git branch -a | grep " releases/gcc-[10|11|9]"
releases/gcc-10
releases/gcc-11
releases/gcc-9
?
The current state of supported branches is:
Branch YP gcc ver Latest gcc ver Upgrade needed?
------ ---------- -------------- ---------------
master 11.2.0 11.2.0 No
honister 11.2.0 11.2.0 No
hardknott 10.2.0 10.3.0 Yes
dunfell 9.3.0 9.4.0 Yes
https://gcc.gnu.org/releases.html
so please check with upstream to see what the plan is for
the 9-11 release branches and this CVE and report back here.
Feel free to volunteer backport patches to gcc upstream if needed.
Are people CCed okay with upgrading gcc to the latest release or
ideally the next dot releases that will include a fix for this CVE
if it happens in the coming month or so?
--><-- snip --><--
--
# Randy MacLeod
# Wind River Linux
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [OE-core] [PATCH] gcc: Fix CVE-2021-42574
2021-12-14 17:31 ` [OE-core] " Randy MacLeod
@ 2021-12-14 17:57 ` Khem Raj
2021-12-15 3:59 ` pgowda cve
0 siblings, 1 reply; 4+ messages in thread
From: Khem Raj @ 2021-12-14 17:57 UTC (permalink / raw)
To: Randy MacLeod
Cc: Pgowda, Patches and discussions about the oe-core layer, Mittal,
Anuj, steve, Richard Purdie, Randy MacLeod, umesh kalappa0
On Tue, Dec 14, 2021 at 9:31 AM Randy MacLeod
<randy.macleod@windriver.com> wrote:
>
> On 2021-12-14 5:46 a.m., Pgowda wrote:
> > Upstream-Status: Backport [https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=bd5e882cf6e0def3dd1bc106075d59a303fe0d1e]
> > Upstream-Status: Backport [https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=51c500269bf53749b107807d84271385fad35628]
> > Upstream-Status: Backport [https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=1a7f2c0774129750fdf73e9f1b78f0ce983c9ab3]
> > Upstream-Status: Backport [https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=bef32d4a28595e933f24fef378cf052a30b674a7]
>
> Ugh, that's quite a bit of patch to fix this bi-directional Unicode
> input attack.
> I'm fine with these changes though.
>
>
> I do wonder about how or if we should fix the CVE in older releases.
this is adding a new warning to help mitigate the problem, this is not
a gcc CVE per se.
so perhaps backporting to older branches makes sense, this looks ok
for 11.x here
>
> For example, has or is there an indication that gcc upstream will,
> be backporting these patches to:
>
> $ git branch -a | grep " releases/gcc-[10|11|9]"
>
> releases/gcc-10
>
> releases/gcc-11
>
> releases/gcc-9
>
>
> ?
>
> The current state of supported branches is:
>
> Branch YP gcc ver Latest gcc ver Upgrade needed?
> ------ ---------- -------------- ---------------
> master 11.2.0 11.2.0 No
> honister 11.2.0 11.2.0 No
> hardknott 10.2.0 10.3.0 Yes
> dunfell 9.3.0 9.4.0 Yes
>
> https://gcc.gnu.org/releases.html
>
>
> so please check with upstream to see what the plan is for
> the 9-11 release branches and this CVE and report back here.
> Feel free to volunteer backport patches to gcc upstream if needed.
>
> Are people CCed okay with upgrading gcc to the latest release or
> ideally the next dot releases that will include a fix for this CVE
> if it happens in the coming month or so?
I think doing a bug fix dot release upgrade might be ok. Although we
would have to do some good amount of testing. But I am in favor
>
>
> --><-- snip --><--
>
> --
> # Randy MacLeod
> # Wind River Linux
>
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [OE-core] [PATCH] gcc: Fix CVE-2021-42574
2021-12-14 17:57 ` Khem Raj
@ 2021-12-15 3:59 ` pgowda cve
0 siblings, 0 replies; 4+ messages in thread
From: pgowda cve @ 2021-12-15 3:59 UTC (permalink / raw)
To: Khem Raj
Cc: Randy MacLeod, Patches and discussions about the oe-core layer,
Mittal, Anuj, steve, Richard Purdie, Randy MacLeod,
umesh kalappa0
Hi,
> this is adding a new warning to help mitigate the problem, this is not
> a gcc CVE per se.
> so perhaps backporting to older branches makes sense, this looks ok
The patch "0001-CVE-2021-42574.patch" is a dependency patch required
for these 3 CVE patches.
It adds 2 MACRO definitions that are present in the CVE patches.
We can just implement those macros and drop the complete patch which
is quite large.
Please let me know if we keep the patches as is or just implement the
macros to make patch smaller?
Thanks,
pgowda
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2021-12-15 4:00 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-12-14 10:46 [PATCH] gcc: Fix CVE-2021-42574 Pgowda
2021-12-14 17:31 ` [OE-core] " Randy MacLeod
2021-12-14 17:57 ` Khem Raj
2021-12-15 3:59 ` pgowda cve
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