REL_18_4
Install our "missing" script where PGXS builds can find it.
Update config/ax_pthread.m4 to latest upstream version.
Allow PG_PRINTF_ATTRIBUTE to be different in C and C++ code.
Simplify checking for xlocale.h
Fix configure's AC_CHECK_DECLS tests to work correctly with clang.
Update copyright for 2025
Update config.guess and config.sub
Rename configure.in to configure.ac
Fix install-strip on Mac OS X
Don't put library-supplied -L/-I switches before user-supplied ones.
meson: Add initial version of meson based build system
Remove cvs keywords from all files.
Remove MSVC scripts
Fix collection of typos in the code and the documentation
Fix vpath build
Unify DLSUFFIX on Darwin
configure: More use of AC_ARG_VAR