Re: autopoint and AM_ICONV, IT_PROG_INTLTOOL

Bruno Haible via Discussion list for the autoconf build system <[email protected]> Wed, 01 Apr 2026 18:48:09 +0200
Newsgroups gmane.comp.sysutils.autoconf.general
Organization GNU
Message-ID <1784524.Al9bMxBtPW@nimes>
[Redirecting to [email protected].]

T=C4=B3l 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.

Things depend on the degree of compatibility of a language version and its
previous version.

=46or C, ISO C 23 is mostly compatible to the previous ISO C 17. We have be=
en
testing the AC_PROG_CC that enables C23 mode automatically for more than a
year before releasing it in Autoconf 2.73 (in Gnulib: since 2024-11-17),
and encountered issues only in two areas:
  - function pointer types with no parameters (() was equivalent to (...)
    before C23),
  - the 'register' keyword.

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.

=46or C++, on the other hand, the incompabilities from C++17 to C++20 are
large enough that AC_PROG_CXX does *not* attempt to force C++20 on every
package's compilation.

Bruno

[1] https://cgit.freebsd.org/ports/commit/?id=3D4c463df3afd4e57a851c625e87f=
d729179785c79