autoconf-2.72

[Bruce Dubbs]

New minor version.

"There have been 171 commits by 17 people in the 151 weeks since 2.71."

Noteworthy changes in release 2.72 (2023-12-22) [release]

Backward incompatibilities

• Configure scripts no longer support pre-1989 C compilers.
• Autoconf developers now need Perl 5.10 (2007) or later.
• Autoconf users now need GNU M4 1.4.8 (2006) or later.
• Some m4sh diversions have been renumbered.
• AC_FUNC_GETGROUPS and AC_TYPE_GETGROUPS no longer run test programs.
• All internal uses of AC_EGREP_CPP and AC_EGREP_HEADER have been removed.

New features

• Support for ensuring time_t is Y2038-safe
• AC_USE_SYSTEM_EXTENSIONS now enables C23 Annex F extensions by defining STDC_WANT_IEC_60559_EXT.

Obsolete features and new warnings

• Autoconf now quotes 'like this' instead of `like this'.
• AC_PROG_GCC_TRADITIONAL no longer does anything.

Notable bug fixes

• autom4te now uses fine-grained file timestamps
• AC_HEADER_STDBOOL, AC_CHECK_HEADER_STDBOOL are obsolescent and less picky.
• AC_PROG_MKDIR_P now falls back on plain 'mkdir -p'
• Better diagnostics for calling m4_warn() with a bad first argument
• Improved compatibility with a wide variety of systems and tools including CheriBSD, Darwin (macOS), GNU Guix, OS/2, z/OS, Bash 5.2, the BusyBox shell and utilities, Clang/LLVM version 16, the upcoming GCC version 14, etc.

Known bugs

• AC_SYS_LARGEFILE and AC_SYS_YEAR2038 only work correctly in C mode.