On Wed, Apr 1, 2026, at 12:48 PM, Bruno Haible via Discussion list for the autoconf build system wrote: > [Redirecting to [email protected].] > > Tijl Coosemans wrote: >> Autoconf 2.73 is more problematic. They've changed AC_PROG_CC to enable >> C23 mode if the compiler supports it, but old code doesn't magically >> become C23 compatible of course. IMHO they should leave old macros >> alone and introduce AC_PROG_C23 or something. > > For C, ISO C 23 is mostly compatible to the previous ISO C 17. ... > In the FreeBSD ports, it appears that only 7 out of ca. 35000 packages are > affected by this change [1]. Which I would consider as a very small amount of > breakage.
It's a small amount of breakage, but it's still a lot more than the _no_ breakage that the C committee _used_ to strive for. :-/ We (Autoconf) have had a feature request open for quite some time now for letting the configure script control exactly which version(s) of each language standard are acceptable: https://savannah.gnu.org/support/index.php?110286 I do not have time to work on it myself anytime soon but I would be delighted to guide anyone who does have the time to work on it. zw
