pgsql: Replace obsolete autoconf macros with their modern replacements.

Replace obsolete autoconf macros with their modern replacements.

AC_TRY_COMPILE(...) -> AC_COMPILE_IFELSE([AC_LANG_PROGRAM(...)])
AC_TRY_LINK(...) -> AC_LINK_IFELSE([AC_LANG_PROGRAM(...)])
AC_TRY_RUN(...) -> AC_RUN_IFELSE([AC_LANG_PROGRAM(...)])
AC_LANG_SAVE/RESTORE -> AC_LANG_PUSH/POP
AC_DECL_SYS_SIGLIST -> AC_CHECK_DECLS(...) (per snippet in autoconf manual)

Also use AC_LANG_SOURCE instead of AC_LANG_PROGRAM, where the main()
function is not needed.

With these changes, autoconf -Wall doesn't complain anymore.

Andreas Karlsson

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/a2edb023d08778c3346bbbf4ca82ef7f6e9283eb

Modified Files
--------------
config/ac_func_accept_argtypes.m4 | 6 +--
config/acx_pthread.m4 | 9 ++---
config/c-compiler.m4 | 70 ++++++++++++++++----------------
config/c-library.m4 | 36 ++++++++---------
config/programs.m4 | 4 +-
configure | 28 -------------
configure.in | 80 ++++++++++++++++++++-----------------
7 files changed, 107 insertions(+), 126 deletions(-)