GNU bug report logs - #63365
30.0.50; GCC 13.1 breaks building Emacs with native-compilation

Previous Next

Full log

View this message in rfc822 format

From: Cyril Arnould <cyril.arnould <at> outlook.com>
To: Andrea Corallo <acorallo <at> gnu.org>
Cc: "63365 <at> debbugs.gnu.org" <63365 <at> debbugs.gnu.org>, "eliz <at> gnu.org" <eliz <at> gnu.org>, 65727 <at> debbugs.gnu.org, Arash Esbati <arash <at> gnu.org>, András Svraka <svraka.andras <at> gmail.com>
Subject: bug#63365: bug#65727: 30.0.50; Build failure in MSYS2 when --with-native-compilation
Date: Wed, 15 May 2024 01:29:40 +0200

> Interesting, would you mind instead of using 'printf' to try using
> '__attribute__((optimize("O0")))' on the function to verify that the
> issue is really an optimization?

With the following, the build fails:


diff --git a/src/thread.c b/src/thread.c
index 040ca39511e..ffdcf420af0 100644
--- a/src/thread.c
+++ b/src/thread.c
@@ -692,6 +692,7 @@ mark_threads_callback (void *ignore)
     }
 }

+__attribute__((optimize("O0")))
 void
 mark_threads (void)
 {


I hope this was correct? If I replace it with
'__attribute__((optimize("no-optimize-sibling-calls")))', the build
succeeds again.

I therefore tried to compile the entirety of thread.c with -O0
instead, upon which the build succeeded again. I'll try to add the
'__attribute__((optimize("O0")))' in more thread.c functions to see
which ones need it for a successful build (unless you have a better
suggestion?).

To summarize the current state:

thread.c compiled with -O2: build fails
thread.c compiled with -O2 -fno-optimize-sibling-calls: build succeeds
thread.c compiled with -O0: build succeeds

thread.c compiled with -O2 and
- mark_threads with printf: build succeeds
- mark_threads with 
__attribute__((optimize("no-optimize-sibling-calls"))): build succeeds
- mark_threads with __attribute__((optimize("O0"))): build fails

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.