Fwd: Bug#1097346: m4: ftbfs with GCC-15

[Santiago Vila]

Hello.

I received the following report from the Debian BTS.

m4 fails to build from source with gcc 15.

For the Debian package, I'm going to add -std=c17 to CFLAGS
in the meantime, but a new official release would be nice.

Thanks.

-------- Mensaje reenviado --------
Asunto: Bug#1097346: m4: ftbfs with GCC-15
Resent-Date: Mon, 17 Feb 2025 17:37:49 +0000
Resent-From: Matthias Klose <doko@debian.org>
Fecha: Mon, 17 Feb 2025 17:36:07 +0000
De: Matthias Klose <doko@debian.org>

Package: src:m4
Version: 1.4.19-5
Severity: important
Tags: sid forky
User: debian-gcc@lists.debian.org
Usertags: ftbfs-gcc-15

[...]

The full build log can be found at:
http://qa-logs.debian.net/2025/02/16/amd64exp/m4_1.4.19-5_unstable_gccexp.log.gz
The last lines of the build log are at the end of this report.

[...]

gcc  -I.   -Wdate-time -D_FORTIFY_SOURCE=2  -g -O2 
-Werror=implicit-function-declaration 
-ffile-prefix-map=/build/reproducible-path/m4-1.4.19=. -fstack-protector-strong 
-fstack-clash-protection -fcf-protection -c -o c-stack.o c-stack.c
In file included from gl_avltree_oset.h:21,
                 from gl_avltree_oset.c:21:
gl_oset.h:275:1: warning: 'nodiscard' attribute ignored [-Wattributes]
  275 | GL_OSET_INLINE _GL_ATTRIBUTE_NODISCARD int
      | ^~~~~~~~~~~~~~
gl_oset.h:275:40: error: expected identifier or '(' before 'int'
  275 | GL_OSET_INLINE _GL_ATTRIBUTE_NODISCARD int
      |                                        ^~~
make[4]: *** [Makefile:2877: gl_avltree_oset.o] Error 1
make[4]: *** Waiting for unfinished jobs....
make[4]: Leaving directory '/build/reproducible-path/m4-1.4.19/lib'
make[3]: *** [Makefile:2487: all] Error 2
make[3]: Leaving directory '/build/reproducible-path/m4-1.4.19/lib'
make[2]: *** [Makefile:2024: all-recursive] Error 1
make[2]: Leaving directory '/build/reproducible-path/m4-1.4.19'
make[1]: *** [Makefile:1980: all] Error 2
make[1]: Leaving directory '/build/reproducible-path/m4-1.4.19'
dh_auto_build: error: make -j8 returned exit code 2
make: *** [debian/rules:8: binary] Error 25
dpkg-buildpackage: error: debian/rules binary subprocess returned exit status 2