[PATCH 0/3 v4] annotations

[PATCH 0/3 v4] annotations

[Julia Lawall]

A fourth attempt at supporting file location annotations.

The changes are minor in response to David's comments.  In particular, it
does not seem possible to eliminate the linking of the new part of the
position list in srcpos_extend.  That part of the list has to be copied to
avoid loops and there is no way to know whether the elements are referenced
elsewhere.

[PATCH 1/3 v4] annotations: check for NULL position

[Julia Lawall]

Check for NULL position and NULL filename.

Signed-off-by: Julia Lawall <Julia.Lawall-L2FTfq7BK8M@public.gmane.org>
Signed-off-by: Frank Rowand <frank.rowand-7U/KSKJipcs@public.gmane.org>
Reviewed-by: David Gibson <david-xT8FGy+AXnRB3Ne2BGzF6laj5H9X9Tb+@public.gmane.org>
---
v4: no change

 srcpos.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/srcpos.c b/srcpos.c
index cb6ed0e..9dd3297 100644
--- a/srcpos.c
+++ b/srcpos.c
@@ -244,12 +244,20 @@ srcpos_copy(struct srcpos *pos)
 char *
 srcpos_string(struct srcpos *pos)
 {
-	const char *fname = "<no-file>";
+	const char *fname;
 	char *pos_str;
 
-	if (pos->file && pos->file->name)
-		fname = pos->file->name;
+	if (!pos) {
+		xasprintf(&pos_str, "<no-file>:<no-line>");
+		return pos_str;
+	}
 
+	if (!pos->file)
+		fname = "<no-file>";
+	else if (!pos->file->name)
+		fname = "<no-filename>";
+	else
+		fname = pos->file->name;
 
 	if (pos->first_line != pos->last_line)
 		xasprintf(&pos_str, "%s:%d.%d-%d.%d", fname,
-- 
2.7.4

[PATCH 2/3 v4] annotations: add positions

[Julia Lawall]

The parser is extended to record positions, in build_node,
build_node_delete, and build_property.

srcpos structures are added to the property and node types, and to the
parameter lists of the above functions that construct these types.
Nodes and properties that are created by the compiler rather than from
parsing source code have NULL as the srcpos value.

merge_nodes, defined in livetree.c uses srcpos_extend to combine
multiple positions, resulting in a list of positions.  srcpos_extend is
defined in srcpos.c and removes duplicates.  As srcpos_extend is
performing a union, it is O(n^2).  The recursion serves to copy the new
list and then add it to the front of the old one.  Using recursion keeps
the positions in order from newer to older.  On each recursive call, the
current element is compared against each element in the proposed new
tail, to avoid duplicates.  Since the list of positions is only extended
in srcpos_extend, and srcpos_extend does not produce lists with
duplicates, it is not necessary to check for the current element in the
tail of its own list.

Another change to srcpos.c is to make srcpos_copy always do a full copy,
including a copy of the file substructure.  This is required because
when dtc is used on the output of cpp, the successive detected file
names overwrite the file name in the file structure.  The next field
does not need to be deep copied, because it is only updated in newly
copied positions and the positions to which it points have also been
copied.  File names are only updated in uncopied position structures.

Signed-off-by: Julia Lawall <Julia.Lawall-L2FTfq7BK8M@public.gmane.org>
Signed-off-by: Frank Rowand <frank.rowand-7U/KSKJipcs@public.gmane.org>
---

v4:

* Free old_prop->srcpos added in merge_nodes
* Dropped irrelevant whitespace changes around add_orphan_node
* Dropped test on xmalloc in srcpos_copy
* Added comments in the log message to justify the definition of
  srcpos_extend.  Eliminate some unnecessary checks by only checking in the
  newtail list, and not the copied one.

 dtc-parser.y | 13 ++++++++-----
 dtc.h        | 10 +++++++---
 flattree.c   |  4 ++--
 fstree.c     |  5 +++--
 livetree.c   | 37 +++++++++++++++++++++++++++----------
 srcpos.c     | 40 ++++++++++++++++++++++++++++++++++++++++
 srcpos.h     |  3 +++
 7 files changed, 90 insertions(+), 22 deletions(-)

diff --git a/dtc-parser.y b/dtc-parser.y
index 44af170..2bcdcab 100644
--- a/dtc-parser.y
+++ b/dtc-parser.y
@@ -175,7 +175,10 @@ devicetree:
 			 */
 			if (!($<flags>-1 & DTSF_PLUGIN))
 				ERROR(&@2, "Label or path %s not found", $1);
-			$$ = add_orphan_node(name_node(build_node(NULL, NULL), ""), $2, $1);
+			$$ = add_orphan_node(
+					name_node(build_node(NULL, NULL, NULL),
+						  ""),
+					$2, $1);
 		}
 	| devicetree DT_LABEL DT_REF nodedef
 		{
@@ -224,7 +227,7 @@ devicetree:
 nodedef:
 	  '{' proplist subnodes '}' ';'
 		{
-			$$ = build_node($2, $3);
+			$$ = build_node($2, $3, &@$);
 		}
 	;
 
@@ -242,11 +245,11 @@ proplist:
 propdef:
 	  DT_PROPNODENAME '=' propdata ';'
 		{
-			$$ = build_property($1, $3);
+			$$ = build_property($1, $3, &@$);
 		}
 	| DT_PROPNODENAME ';'
 		{
-			$$ = build_property($1, empty_data);
+			$$ = build_property($1, empty_data, &@$);
 		}
 	| DT_DEL_PROP DT_PROPNODENAME ';'
 		{
@@ -521,7 +524,7 @@ subnode:
 		}
 	| DT_DEL_NODE DT_PROPNODENAME ';'
 		{
-			$$ = name_node(build_node_delete(), $2);
+			$$ = name_node(build_node_delete(&@$), $2);
 		}
 	| DT_LABEL subnode
 		{
diff --git a/dtc.h b/dtc.h
index 3b18a42..42106c2 100644
--- a/dtc.h
+++ b/dtc.h
@@ -149,6 +149,7 @@ struct property {
 	struct property *next;
 
 	struct label *labels;
+	struct srcpos *srcpos;
 };
 
 struct node {
@@ -168,6 +169,7 @@ struct node {
 
 	struct label *labels;
 	const struct bus_type *bus;
+	struct srcpos *srcpos;
 };
 
 #define for_each_label_withdel(l0, l) \
@@ -194,13 +196,15 @@ struct node {
 void add_label(struct label **labels, char *label);
 void delete_labels(struct label **labels);
 
-struct property *build_property(char *name, struct data val);
+struct property *build_property(char *name, struct data val,
+	struct srcpos *srcpos);
 struct property *build_property_delete(char *name);
 struct property *chain_property(struct property *first, struct property *list);
 struct property *reverse_properties(struct property *first);
 
-struct node *build_node(struct property *proplist, struct node *children);
-struct node *build_node_delete(void);
+struct node *build_node(struct property *proplist, struct node *children,
+			struct srcpos *srcpos);
+struct node *build_node_delete(struct srcpos *srcpos);
 struct node *name_node(struct node *node, char *name);
 struct node *chain_node(struct node *first, struct node *list);
 struct node *merge_nodes(struct node *old_node, struct node *new_node);
diff --git a/flattree.c b/flattree.c
index 8d268fb..61b3e4d 100644
--- a/flattree.c
+++ b/flattree.c
@@ -692,7 +692,7 @@ static struct property *flat_read_property(struct inbuf *dtbuf,
 
 	val = flat_read_data(dtbuf, proplen);
 
-	return build_property(name, val);
+	return build_property(name, val, NULL);
 }
 
 
@@ -750,7 +750,7 @@ static struct node *unflatten_tree(struct inbuf *dtbuf,
 	char *flatname;
 	uint32_t val;
 
-	node = build_node(NULL, NULL);
+	node = build_node(NULL, NULL, NULL);
 
 	flatname = flat_read_string(dtbuf);
 
diff --git a/fstree.c b/fstree.c
index ae7d06c..1e7eeba 100644
--- a/fstree.c
+++ b/fstree.c
@@ -34,7 +34,7 @@ static struct node *read_fstree(const char *dirname)
 	if (!d)
 		die("Couldn't opendir() \"%s\": %s\n", dirname, strerror(errno));
 
-	tree = build_node(NULL, NULL);
+	tree = build_node(NULL, NULL, NULL);
 
 	while ((de = readdir(d)) != NULL) {
 		char *tmpname;
@@ -60,7 +60,8 @@ static struct node *read_fstree(const char *dirname)
 			} else {
 				prop = build_property(xstrdup(de->d_name),
 						      data_copy_file(pfile,
-								     st.st_size));
+								     st.st_size),
+						      NULL);
 				add_property(tree, prop);
 				fclose(pfile);
 			}
diff --git a/livetree.c b/livetree.c
index 57b7db2..99aa2c3 100644
--- a/livetree.c
+++ b/livetree.c
@@ -19,6 +19,7 @@
  */
 
 #include "dtc.h"
+#include "srcpos.h"
 
 /*
  * Tree building functions
@@ -50,7 +51,8 @@ void delete_labels(struct label **labels)
 		label->deleted = 1;
 }
 
-struct property *build_property(char *name, struct data val)
+struct property *build_property(char *name, struct data val,
+				struct srcpos *srcpos)
 {
 	struct property *new = xmalloc(sizeof(*new));
 
@@ -58,6 +60,7 @@ struct property *build_property(char *name, struct data val)
 
 	new->name = name;
 	new->val = val;
+	new->srcpos = srcpos_copy(srcpos);
 
 	return new;
 }
@@ -97,7 +100,8 @@ struct property *reverse_properties(struct property *first)
 	return head;
 }
 
-struct node *build_node(struct property *proplist, struct node *children)
+struct node *build_node(struct property *proplist, struct node *children,
+			struct srcpos *srcpos)
 {
 	struct node *new = xmalloc(sizeof(*new));
 	struct node *child;
@@ -106,6 +110,7 @@ struct node *build_node(struct property *proplist, struct node *children)
 
 	new->proplist = reverse_properties(proplist);
 	new->children = children;
+	new->srcpos = srcpos_copy(srcpos);
 
 	for_each_child(new, child) {
 		child->parent = new;
@@ -114,13 +119,14 @@ struct node *build_node(struct property *proplist, struct node *children)
 	return new;
 }
 
-struct node *build_node_delete(void)
+struct node *build_node_delete(struct srcpos *srcpos)
 {
 	struct node *new = xmalloc(sizeof(*new));
 
 	memset(new, 0, sizeof(*new));
 
 	new->deleted = 1;
+	new->srcpos = srcpos_copy(srcpos);
 
 	return new;
 }
@@ -169,6 +175,8 @@ struct node *merge_nodes(struct node *old_node, struct node *new_node)
 
 				old_prop->val = new_prop->val;
 				old_prop->deleted = 0;
+				free(old_prop->srcpos);
+				old_prop->srcpos = new_prop->srcpos;
 				free(new_prop);
 				new_prop = NULL;
 				break;
@@ -209,6 +217,8 @@ struct node *merge_nodes(struct node *old_node, struct node *new_node)
 			add_child(old_node, new_child);
 	}
 
+	old_node->srcpos = srcpos_extend(new_node->srcpos, old_node->srcpos);
+
 	/* The new node contents are now merged into the old node.  Free
 	 * the new node. */
 	free(new_node);
@@ -227,12 +237,12 @@ struct node * add_orphan_node(struct node *dt, struct node *new_node, char *ref)
 	d = data_add_marker(d, REF_PHANDLE, ref);
 	d = data_append_integer(d, 0xffffffff, 32);
 
-	p = build_property("target", d);
+	p = build_property("target", d, NULL);
 
 	xasprintf(&name, "fragment@%u",
 			next_orphan_fragment++);
 	name_node(new_node, "__overlay__");
-	node = build_node(p, new_node);
+	node = build_node(p, new_node, NULL);
 	name_node(node, name);
 
 	add_child(dt, node);
@@ -331,7 +341,8 @@ void append_to_property(struct node *node,
 		p->val = d;
 	} else {
 		d = data_append_data(empty_data, data, len);
-		p = build_property(name, d);
+		/* used from fixup or local_fixup, so no position */
+		p = build_property(name, d, NULL);
 		add_property(node, p);
 	}
 }
@@ -587,13 +598,17 @@ cell_t get_node_phandle(struct node *root, struct node *node)
 	    && (phandle_format & PHANDLE_LEGACY))
 		add_property(node,
 			     build_property("linux,phandle",
-					    data_append_cell(empty_data, phandle)));
+					    data_append_cell(empty_data,
+							     phandle),
+					    NULL));
 
 	if (!get_property(node, "phandle")
 	    && (phandle_format & PHANDLE_EPAPR))
 		add_property(node,
 			     build_property("phandle",
-					    data_append_cell(empty_data, phandle)));
+					    data_append_cell(empty_data,
+							     phandle),
+					    NULL));
 
 	/* If the node *does* have a phandle property, we must
 	 * be dealing with a self-referencing phandle, which will be
@@ -767,7 +782,7 @@ static struct node *build_and_name_child_node(struct node *parent, char *name)
 {
 	struct node *node;
 
-	node = build_node(NULL, NULL);
+	node = build_node(NULL, NULL, NULL);
 	name_node(node, xstrdup(name));
 	add_child(parent, node);
 
@@ -827,9 +842,11 @@ static void generate_label_tree_internal(struct dt_info *dti,
 			}
 
 			/* insert it */
+			/* no position information for symbols and aliases */
 			p = build_property(l->label,
 				data_copy_mem(node->fullpath,
-						strlen(node->fullpath) + 1));
+					      strlen(node->fullpath) + 1),
+				NULL);
 			add_property(an, p);
 		}
 
diff --git a/srcpos.c b/srcpos.c
index 9dd3297..c6688e7 100644
--- a/srcpos.c
+++ b/srcpos.c
@@ -207,6 +207,7 @@ struct srcpos srcpos_empty = {
 	.last_line = 0,
 	.last_column = 0,
 	.file = NULL,
+	.next = NULL,
 };
 
 void srcpos_update(struct srcpos *pos, const char *text, int len)
@@ -234,13 +235,52 @@ struct srcpos *
 srcpos_copy(struct srcpos *pos)
 {
 	struct srcpos *pos_new;
+	struct srcfile_state *srcfile_state;
+
+	if (!pos)
+		return NULL;
 
 	pos_new = xmalloc(sizeof(struct srcpos));
 	memcpy(pos_new, pos, sizeof(struct srcpos));
 
+	if (pos_new) {
+		/* allocate without free */
+		srcfile_state = xmalloc(sizeof(struct srcfile_state));
+		memcpy(srcfile_state, pos->file, sizeof(struct srcfile_state));
+
+		pos_new->file = srcfile_state;
+	}
+
 	return pos_new;
 }
 
+static bool same_pos(struct srcpos *p1, struct srcpos *p2)
+{
+	return (p1->first_line == p2->first_line &&
+		p1->first_column == p2->first_column &&
+		p1->last_line == p2->last_line &&
+		p1->last_column == p2->last_column &&
+		!strcmp(p1->file->name, p2->file->name));
+}
+
+struct srcpos *srcpos_extend(struct srcpos *pos, struct srcpos *newtail)
+{
+	struct srcpos *next, *p;
+
+	if (!pos)
+		return newtail;
+
+	next = srcpos_extend(pos->next, newtail);
+
+	for (p = newtail; p != NULL; p = p->next)
+		if (same_pos(pos, p))
+			return next;
+
+	pos = srcpos_copy(pos);
+	pos->next = next;
+	return pos;
+}
+
 char *
 srcpos_string(struct srcpos *pos)
 {
diff --git a/srcpos.h b/srcpos.h
index 9ded12a..d88e7cb 100644
--- a/srcpos.h
+++ b/srcpos.h
@@ -74,6 +74,7 @@ struct srcpos {
     int last_line;
     int last_column;
     struct srcfile_state *file;
+    struct srcpos *next;
 };
 
 #define YYLTYPE struct srcpos
@@ -105,6 +106,8 @@ extern struct srcpos srcpos_empty;
 
 extern void srcpos_update(struct srcpos *pos, const char *text, int len);
 extern struct srcpos *srcpos_copy(struct srcpos *pos);
+extern struct srcpos *srcpos_extend(struct srcpos *new_srcpos,
+				    struct srcpos *old_srcpos);
 extern char *srcpos_string(struct srcpos *pos);
 
 extern void PRINTF(3, 0) srcpos_verror(struct srcpos *pos, const char *prefix,
-- 
2.7.4

[PATCH 3/3 v4] annotations: add the annotation functionality

[Julia Lawall]

This commit provides two new command-line options:

--annotate (abbreviated -T)
--annotate-full (abbreviated -F)

--annotate provides one or more filenames and line numbers indicating
the origin of a given line.  The filename is expressed relative the the
filename provided on the command line.  Nothing is printed for overlays,
etc.

--annotate-full provides one or more tuples of: filename, starting line,
starting column, ending line ending column.  The full path is given for
the file name.  Overlays, etc are annotated with <no-file>:<no-line>.

--annotate-full	may be too verbose for normal use.

There are numerous changes in srcpos to provide the relative filenames
(variables initial_path, initial_pathlen and initial_cpp, new functions
set_initial_path and shorten_to_initial_path, and changes in
srcfile_push and srcpos_set_line).  The change in srcpos_set_line takes
care of the case where cpp is used as a preprocessor.  In that case the
initial file name is not the one provided on the command line but the
one found at the beginnning of the cpp output.

The new functions srcpos_string_comment, srcpos_string_first, and
srcpos_string_last print the annotations.  srcpos_string_comment is
recursive to print a list of source file positions.

Various changes are sprinkled throughout treesource.c to print the
annotations.

Signed-off-by: Julia Lawall <Julia.Lawall-L2FTfq7BK8M@public.gmane.org>
Signed-off-by: Frank Rowand <frank.rowand-7U/KSKJipcs@public.gmane.org>
---
v4: no change

 dtc.c        |  19 ++++++++-
 dtc.h        |   2 +
 srcpos.c     | 124 +++++++++++++++++++++++++++++++++++++++++++++++++++++------
 srcpos.h     |   2 +
 treesource.c |  47 +++++++++++++++++++---
 5 files changed, 176 insertions(+), 18 deletions(-)

diff --git a/dtc.c b/dtc.c
index c36994e..10786a4 100644
--- a/dtc.c
+++ b/dtc.c
@@ -35,6 +35,8 @@ int phandle_format = PHANDLE_EPAPR;	/* Use linux,phandle or phandle properties *
 int generate_symbols;	/* enable symbols & fixup support */
 int generate_fixups;		/* suppress generation of fixups on symbol support */
 int auto_label_aliases;		/* auto generate labels -> aliases */
+bool annotate;		 /* =false, annotate .dts with input source location */
+bool annotate_full; /* =false, annotate .dts with full input source location */
 
 static int is_power_of_2(int x)
 {
@@ -60,7 +62,7 @@ static void fill_fullpaths(struct node *tree, const char *prefix)
 
 /* Usage related data. */
 static const char usage_synopsis[] = "dtc [options] <input file>";
-static const char usage_short_opts[] = "qI:O:o:V:d:R:S:p:a:fb:i:H:sW:E:@Ahv";
+static const char usage_short_opts[] = "qI:O:o:V:d:R:S:p:a:fb:i:H:sW:E:@ATFhv";
 static struct option const usage_long_opts[] = {
 	{"quiet",            no_argument, NULL, 'q'},
 	{"in-format",         a_argument, NULL, 'I'},
@@ -81,6 +83,8 @@ static struct option const usage_long_opts[] = {
 	{"error",             a_argument, NULL, 'E'},
 	{"symbols",	     no_argument, NULL, '@'},
 	{"auto-alias",       no_argument, NULL, 'A'},
+	{"annotate",         no_argument, NULL, 'T'},
+	{"annotate-full",    no_argument, NULL, 'F'},
 	{"help",             no_argument, NULL, 'h'},
 	{"version",          no_argument, NULL, 'v'},
 	{NULL,               no_argument, NULL, 0x0},
@@ -114,6 +118,8 @@ static const char * const usage_opts_help[] = {
 	"\n\tEnable/disable errors (prefix with \"no-\")",
 	"\n\tEnable generation of symbols",
 	"\n\tEnable auto-alias of labels",
+	"\n\tAnnotate output .dts with input source file and line",
+	"\n\tAnnotate output .dts with input source file (full path) line and column",
 	"\n\tPrint this help and exit",
 	"\n\tPrint version and exit",
 	NULL,
@@ -259,6 +265,13 @@ int main(int argc, char *argv[])
 		case 'A':
 			auto_label_aliases = 1;
 			break;
+		case 'F':
+			annotate = true;
+			annotate_full = true;
+			break;
+		case 'T':
+			annotate = true;
+			break;
 
 		case 'h':
 			usage(NULL);
@@ -297,6 +310,10 @@ int main(int argc, char *argv[])
 				outform = "dts";
 		}
 	}
+
+	if (annotate && (!streq(inform, "dts") || !streq(outform, "dts")))
+		die("--annotate and --annotate-full require -I dts -O dts\n");
+
 	if (streq(inform, "dts"))
 		dti = dt_from_source(arg);
 	else if (streq(inform, "fs"))
diff --git a/dtc.h b/dtc.h
index 42106c2..63ba433 100644
--- a/dtc.h
+++ b/dtc.h
@@ -58,6 +58,8 @@ extern int phandle_format;	/* Use linux,phandle or phandle properties */
 extern int generate_symbols;	/* generate symbols for nodes with labels */
 extern int generate_fixups;	/* generate fixups */
 extern int auto_label_aliases;	/* auto generate labels -> aliases */
+extern bool annotate;		/* annotate .dts with input source location */
+extern bool annotate_full;   /* annotate .dts with detailed source location */
 
 #define PHANDLE_LEGACY	0x1
 #define PHANDLE_EPAPR	0x2
diff --git a/srcpos.c b/srcpos.c
index c6688e7..916dc8d 100644
--- a/srcpos.c
+++ b/srcpos.c
@@ -33,6 +33,9 @@ struct search_path {
 /* This is the list of directories that we search for source files */
 static struct search_path *search_path_head, **search_path_tail;
 
+/* Detect infinite include recursion. */
+#define MAX_SRCFILE_DEPTH     (100)
+static int srcfile_depth; /* = 0 */
 
 static char *get_dirname(const char *path)
 {
@@ -51,11 +54,51 @@ static char *get_dirname(const char *path)
 
 FILE *depfile; /* = NULL */
 struct srcfile_state *current_srcfile; /* = NULL */
+static char *initial_path; /* = NULL */
+static int initial_pathlen; /* = 0 */
+static bool initial_cpp = true;
 
-/* Detect infinite include recursion. */
-#define MAX_SRCFILE_DEPTH     (100)
-static int srcfile_depth; /* = 0 */
+static void set_initial_path(char *fname)
+{
+	int i, len = strlen(fname);
 
+	xasprintf(&initial_path, "%s", fname);
+	initial_pathlen = 0;
+	for (i = 0; i != len; i++)
+		if (initial_path[i] == '/')
+			initial_pathlen++;
+}
+
+static char *shorten_to_initial_path(char *fname)
+{
+	char *p1, *p2, *prevslash1 = NULL;
+	int slashes = 0;
+
+	for (p1 = fname, p2 = initial_path; *p1 && *p2; p1++, p2++) {
+		if (*p1 != *p2)
+			break;
+		if (*p1 == '/') {
+			prevslash1 = p1;
+			slashes++;
+		}
+	}
+	p1 = prevslash1 + 1;
+	if (prevslash1) {
+		int diff = initial_pathlen - slashes, i, j;
+		int restlen = strlen(fname) - (p1 - fname);
+		char *res;
+
+		res = xmalloc((3 * diff) + restlen + 1);
+		for (i = 0, j = 0; i != diff; i++) {
+			res[j++] = '.';
+			res[j++] = '.';
+			res[j++] = '/';
+		}
+		strcpy(res + j, p1);
+		return res;
+	}
+	return fname;
+}
 
 /**
  * Try to open a file in a given directory.
@@ -157,6 +200,9 @@ void srcfile_push(const char *fname)
 	srcfile->colno = 1;
 
 	current_srcfile = srcfile;
+
+	if (srcfile_depth == 1)
+		set_initial_path(srcfile->name);
 }
 
 bool srcfile_pop(void)
@@ -243,13 +289,10 @@ srcpos_copy(struct srcpos *pos)
 	pos_new = xmalloc(sizeof(struct srcpos));
 	memcpy(pos_new, pos, sizeof(struct srcpos));
 
-	if (pos_new) {
-		/* allocate without free */
-		srcfile_state = xmalloc(sizeof(struct srcfile_state));
-		memcpy(srcfile_state, pos->file, sizeof(struct srcfile_state));
-
-		pos_new->file = srcfile_state;
-	}
+	/* allocate without free */
+	srcfile_state = xmalloc(sizeof(struct srcfile_state));
+	memcpy(srcfile_state, pos->file, sizeof(struct srcfile_state));
+	pos_new->file = srcfile_state;
 
 	return pos_new;
 }
@@ -260,7 +303,7 @@ static bool same_pos(struct srcpos *p1, struct srcpos *p2)
 		p1->first_column == p2->first_column &&
 		p1->last_line == p2->last_line &&
 		p1->last_column == p2->last_column &&
-		!strcmp(p1->file->name, p2->file->name));
+		streq(p1->file->name, p2->file->name));
 }
 
 struct srcpos *srcpos_extend(struct srcpos *pos, struct srcpos *newtail)
@@ -314,6 +357,60 @@ srcpos_string(struct srcpos *pos)
 	return pos_str;
 }
 
+static char *
+srcpos_string_comment(struct srcpos *pos, bool first_line, bool full)
+{
+	char *pos_str, *fname, *first, *rest;
+
+	if (!pos) {
+		if (full) {
+			xasprintf(&pos_str, "<no-file>:<no-line>");
+			return pos_str;
+		} else {
+			return NULL;
+		}
+	}
+
+	if (!pos->file)
+		fname = "<no-file>";
+	else if (!pos->file->name)
+		fname = "<no-filename>";
+	else if (full)
+		fname = pos->file->name;
+	else
+		fname = shorten_to_initial_path(pos->file->name);
+
+	if (full)
+		xasprintf(&first, "%s:%d:%d-%d:%d", fname,
+			  pos->first_line, pos->first_column,
+			  pos->last_line, pos->last_column);
+	else
+		xasprintf(&first, "%s:%d", fname,
+			  first_line ? pos->first_line : pos->last_line);
+
+	if (pos->next != NULL) {
+		rest = srcpos_string_comment(pos->next, first_line, full);
+		xasprintf(&pos_str, "%s, %s", first, rest);
+		free(first);
+		free(rest);
+	} else {
+		pos_str = first;
+	}
+
+	return pos_str;
+}
+
+char *srcpos_string_first(struct srcpos *pos, bool full)
+{
+	return srcpos_string_comment(pos, true, full);
+}
+
+char *srcpos_string_last(struct srcpos *pos, bool full)
+{
+	return srcpos_string_comment(pos, false, full);
+}
+
+
 void srcpos_verror(struct srcpos *pos, const char *prefix,
 		   const char *fmt, va_list va)
 {
@@ -342,4 +439,9 @@ void srcpos_set_line(char *f, int l)
 {
 	current_srcfile->name = f;
 	current_srcfile->lineno = l;
+
+	if (initial_cpp) {
+		initial_cpp = false;
+		set_initial_path(f);
+	}
 }
diff --git a/srcpos.h b/srcpos.h
index d88e7cb..353c040 100644
--- a/srcpos.h
+++ b/srcpos.h
@@ -109,6 +109,8 @@ extern struct srcpos *srcpos_copy(struct srcpos *pos);
 extern struct srcpos *srcpos_extend(struct srcpos *new_srcpos,
 				    struct srcpos *old_srcpos);
 extern char *srcpos_string(struct srcpos *pos);
+extern char *srcpos_string_first(struct srcpos *pos, bool full);
+extern char *srcpos_string_last(struct srcpos *pos, bool full);
 
 extern void PRINTF(3, 0) srcpos_verror(struct srcpos *pos, const char *prefix,
 					const char *fmt, va_list va);
diff --git a/treesource.c b/treesource.c
index 2461a3d..f454ba4 100644
--- a/treesource.c
+++ b/treesource.c
@@ -199,10 +199,20 @@ static void write_propval(FILE *f, struct property *prop)
 	struct marker *m = prop->val.markers;
 	int nnotstring = 0, nnul = 0;
 	int nnotstringlbl = 0, nnotcelllbl = 0;
+	char *srcstr;
 	int i;
 
 	if (len == 0) {
-		fprintf(f, ";\n");
+		fprintf(f, ";");
+		if (annotate) {
+			srcstr = srcpos_string_first(prop->srcpos,
+						     annotate_full);
+			if (srcstr) {
+				fprintf(f, " /* %s */", srcstr);
+				free(srcstr);
+			}
+		}
+		fprintf(f, "\n");
 		return;
 	}
 
@@ -230,7 +240,15 @@ static void write_propval(FILE *f, struct property *prop)
 		write_propval_bytes(f, prop->val);
 	}
 
-	fprintf(f, ";\n");
+	fprintf(f, ";");
+	if (annotate) {
+		srcstr = srcpos_string_first(prop->srcpos, annotate_full);
+		if (srcstr) {
+			fprintf(f, " /* %s */", srcstr);
+			free(srcstr);
+		}
+	}
+	fprintf(f, "\n");
 }
 
 static void write_tree_source_node(FILE *f, struct node *tree, int level)
@@ -238,14 +256,24 @@ static void write_tree_source_node(FILE *f, struct node *tree, int level)
 	struct property *prop;
 	struct node *child;
 	struct label *l;
+	char *srcstr;
 
 	write_prefix(f, level);
 	for_each_label(tree->labels, l)
 		fprintf(f, "%s: ", l->label);
 	if (tree->name && (*tree->name))
-		fprintf(f, "%s {\n", tree->name);
+		fprintf(f, "%s {", tree->name);
 	else
-		fprintf(f, "/ {\n");
+		fprintf(f, "/ {");
+
+	if (annotate) {
+		srcstr = srcpos_string_first(tree->srcpos, annotate_full);
+		if (srcstr) {
+			fprintf(f, " /* %s */", srcstr);
+			free(srcstr);
+		}
+	}
+	fprintf(f, "\n");
 
 	for_each_property(tree, prop) {
 		write_prefix(f, level+1);
@@ -259,10 +287,17 @@ static void write_tree_source_node(FILE *f, struct node *tree, int level)
 		write_tree_source_node(f, child, level+1);
 	}
 	write_prefix(f, level);
-	fprintf(f, "};\n");
+	fprintf(f, "};");
+	if (annotate) {
+		srcstr = srcpos_string_last(tree->srcpos, annotate_full);
+		if (srcstr) {
+			fprintf(f, " /* %s */", srcstr);
+			free(srcstr);
+		}
+	}
+	fprintf(f, "\n");
 }
 
-
 void dt_to_source(FILE *f, struct dt_info *dti)
 {
 	struct reserve_info *re;
-- 
2.7.4