postgresql/config
Tom Lane 1d97e47883 Allow PG_PRINTF_ATTRIBUTE to be different in C and C++ code.
Although clang claims to be compatible with gcc's printf format
archetypes, this appears to be a falsehood: it likes __syslog__
(which gcc does not, on most platforms) and doesn't accept
gnu_printf.  This means that if you try to use gcc with clang++
or clang with g++, you get compiler warnings when compiling
printf-like calls in our C++ code.  This has been true for quite
awhile, but it's gotten more annoying with the recent appearance
of several buildfarm members that are configured like this.

To fix, run separate probes for the format archetype to use with the
C and C++ compilers, and conditionally define PG_PRINTF_ATTRIBUTE
depending on __cplusplus.

(We could alternatively insist that you not mix-and-match C and
C++ compilers; but if the case works otherwise, this is a poor
reason to insist on that.)

This commit back-patches 0909380e4 into supported branches.

Discussion: https://postgr.es/m/986485.1764825548@sss.pgh.pa.us
Discussion: https://postgr.es/m/3988414.1771950285@sss.pgh.pa.us
Backpatch-through: 14-18
2026-02-25 11:57:26 -05:00
..
ax_pthread.m4 Update config/ax_pthread.m4 to latest upstream version. 2018-11-19 15:05:33 -05:00
c-compiler.m4 Allow PG_PRINTF_ATTRIBUTE to be different in C and C++ code. 2026-02-25 11:57:26 -05:00
c-library.m4 Remove configure probes for sockaddr_storage members. 2022-08-22 17:50:30 +12:00
check_decls.m4 Fix configure's AC_CHECK_DECLS tests to work correctly with clang. 2018-11-19 12:01:47 -05:00
check_modules.pl Pre-beta mechanical code beautification. 2022-05-12 15:17:30 -04:00
config.guess Update config.guess and config.sub 2023-04-12 09:16:19 +02:00
config.sub Fix typos in comments 2023-05-02 12:23:08 +09:00
general.m4 Rename configure.in to configure.ac 2020-07-24 10:42:08 +02:00
install-sh Fix install-strip on Mac OS X 2012-08-21 23:42:43 -04:00
llvm.m4 Don't put library-supplied -L/-I switches before user-supplied ones. 2025-07-29 15:17:41 -04:00
Makefile Install our "missing" script where PGXS builds can find it. 2015-12-11 16:15:05 -05:00
meson.build meson: Add initial version of meson based build system 2022-09-21 22:37:17 -07:00
missing Remove cvs keywords from all files. 2010-09-20 22:08:53 +02:00
perl.m4 Bump minimum Perl version to 5.14 2022-09-14 12:37:04 +07:00
pkg.m4 Fix collection of typos in the code and the documentation 2022-03-15 11:29:35 +09:00
prep_buildtree Fix vpath build 2019-03-27 23:36:00 +01:00
programs.m4 Use --strip-unneeded when stripping static libraries with GNU strip. 2023-04-20 18:12:32 -04:00
python.m4 Unify DLSUFFIX on Darwin 2022-07-06 07:41:33 +02:00
tcl.m4 configure: More use of AC_ARG_VAR 2019-01-18 08:38:34 +01:00