linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Vasily Gorbik <gor@linux.ibm.com>
To: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>,
	Josh Poimboeuf <jpoimboe@redhat.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Stephen Rothwell <sfr@canb.auug.org.au>,
	Ingo Molnar <mingo@redhat.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Mark Rutland <mark.rutland@arm.com>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Namhyung Kim <namhyung@kernel.org>,
	"H. Peter Anvin" <hpa@zytor.com>,
	Masami Hiramatsu <mhiramat@kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Linux Next Mailing List <linux-next@vger.kernel.org>
Subject: [PATCH RESEND 1/1] perf build: Allow nested externs to enable BUILD_BUG() usage
Date: Fri, 9 Oct 2020 14:25:23 +0200	[thread overview]
Message-ID: <patch-1.thread-251403.git-2514037e9477.your-ad-here.call-01602244460-ext-7088@work.hours> (raw)
In-Reply-To: <cover.thread-251403.your-ad-here.call-01602244460-ext-7088@work.hours>

Currently BUILD_BUG() macro is expanded to smth like the following:
   do {
           extern void __compiletime_assert_0(void)
                   __attribute__((error("BUILD_BUG failed")));
           if (!(!(1)))
                   __compiletime_assert_0();
   } while (0);

If used in a function body this obviously would produce build errors
with -Wnested-externs and -Werror.

To enable BUILD_BUG() usage in tools/arch/x86/lib/insn.c which perf
includes in intel-pt-decoder, build perf without -Wnested-externs.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
---
 Resend with no fancy signatures.

 tools/perf/Makefile.config | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
index 854da830b5ca..834061e94e7c 100644
--- a/tools/perf/Makefile.config
+++ b/tools/perf/Makefile.config
@@ -16,7 +16,7 @@ $(shell printf "" > $(OUTPUT).config-detected)
 detected     = $(shell echo "$(1)=y"       >> $(OUTPUT).config-detected)
 detected_var = $(shell echo "$(1)=$($(1))" >> $(OUTPUT).config-detected)
 
-CFLAGS := $(EXTRA_CFLAGS) $(EXTRA_WARNINGS)
+CFLAGS := $(EXTRA_CFLAGS) $(filter-out -Wnested-externs,$(EXTRA_WARNINGS))
 
 include $(srctree)/tools/scripts/Makefile.arch
 
-- 
2.25.4

  reply	other threads:[~2020-10-09 12:25 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-09  4:28 linux-next: build failure after merge of the tip tree Stephen Rothwell
2020-10-09  6:47 ` Vasily Gorbik
2020-10-09  6:47   ` [PATCH 1/1] perf build: Allow nested externs to enable BUILD_BUG() usage Vasily Gorbik
2020-10-09 11:23     ` Jiri Olsa
2020-10-09 12:25       ` Vasily Gorbik
2020-10-09 12:25         ` Vasily Gorbik [this message]
2020-10-09 12:41           ` [PATCH RESEND " Jiri Olsa
2020-10-11 21:59             ` Stephen Rothwell
2020-10-12  5:13               ` Stephen Rothwell
2020-10-13 19:09               ` Arnaldo Carvalho de Melo
2020-10-13 19:07             ` Arnaldo Carvalho de Melo
2020-10-12  7:06           ` Sedat Dilek

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=patch-1.thread-251403.git-2514037e9477.your-ad-here.call-01602244460-ext-7088@work.hours \
    --to=gor@linux.ibm.com \
    --cc=acme@kernel.org \
    --cc=alexander.shishkin@linux.intel.com \
    --cc=hpa@zytor.com \
    --cc=jolsa@redhat.com \
    --cc=jpoimboe@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-next@vger.kernel.org \
    --cc=mark.rutland@arm.com \
    --cc=mhiramat@kernel.org \
    --cc=mingo@redhat.com \
    --cc=namhyung@kernel.org \
    --cc=peterz@infradead.org \
    --cc=sfr@canb.auug.org.au \
    --cc=tglx@linutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).