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

5 files changed, 63 insertions, 62 deletions

diff --git a/config/ac_func_accept_argtypes.m4 b/config/ac_func_accept_argtypes.m4
index a82788dd977..e57f3e6f005 100644
--- a/config/ac_func_accept_argtypes.m4
+++ b/config/ac_func_accept_argtypes.m4
@@ -50,15 +50,15 @@ AC_DEFUN([AC_FUNC_ACCEPT_ARGTYPES],
       for ac_cv_func_accept_arg1 in 'int' 'unsigned int' 'SOCKET'; do
        for ac_cv_func_accept_arg2 in 'struct sockaddr *' 'const struct sockaddr *' 'void *'; do
         for ac_cv_func_accept_arg3 in 'int' 'size_t' 'socklen_t' 'unsigned int' 'void'; do
-         AC_TRY_COMPILE(
+         AC_COMPILE_IFELSE([AC_LANG_SOURCE(
 [#ifdef HAVE_SYS_TYPES_H
 #include <sys/types.h>
 #endif
 #ifdef HAVE_SYS_SOCKET_H
 #include <sys/socket.h>
 #endif
-extern $ac_cv_func_accept_return accept ($ac_cv_func_accept_arg1, $ac_cv_func_accept_arg2, $ac_cv_func_accept_arg3 *);],
-         [], [ac_not_found=no; break 4], [ac_not_found=yes])
+extern $ac_cv_func_accept_return accept ($ac_cv_func_accept_arg1, $ac_cv_func_accept_arg2, $ac_cv_func_accept_arg3 *);])],
+         [ac_not_found=no; break 4], [ac_not_found=yes])
        done
       done
      done
diff --git a/config/acx_pthread.m4 b/config/acx_pthread.m4
index 581164b1e55..793b7b71a45 100644
--- a/config/acx_pthread.m4
+++ b/config/acx_pthread.m4
@@ -5,8 +5,7 @@ dnl upstream changes!
 dnl
 AC_DEFUN([ACX_PTHREAD], [
 AC_REQUIRE([AC_CANONICAL_HOST])
-AC_LANG_SAVE
-AC_LANG_C
+AC_LANG_PUSH([C])
 acx_pthread_ok=no
 
 # We used to check for pthread.h first, but this fails if pthread.h
@@ -122,10 +121,10 @@ for flag in $acx_pthread_flags; do
         # pthread_cleanup_push because it is one of the few pthread
         # functions on Solaris that doesn't have a non-functional libc stub.
         # We try pthread_create on general principles.
-        AC_TRY_LINK([#include <pthread.h>],
+        AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <pthread.h>],
                     [pthread_t th; pthread_join(th, 0);
                      pthread_attr_init(0); pthread_cleanup_push(0, 0);
-                     pthread_create(0,0,0,0); pthread_cleanup_pop(0); ],
+                     pthread_create(0,0,0,0); pthread_cleanup_pop(0); ])],
                     [acx_pthread_ok=yes], [acx_pthread_ok=no])
 
         if test "x$acx_pthread_ok" = xyes; then
@@ -167,5 +166,5 @@ fi
 AC_SUBST(PTHREAD_LIBS)
 AC_SUBST(PTHREAD_CFLAGS)
 
-AC_LANG_RESTORE
+AC_LANG_POP([C])
 ])dnl ACX_PTHREAD
diff --git a/config/c-compiler.m4 b/config/c-compiler.m4
index 4ef0de65a8b..050bfa5c7d7 100644
--- a/config/c-compiler.m4
+++ b/config/c-compiler.m4
@@ -7,8 +7,8 @@
 # Check if the C compiler understands signed types.
 AC_DEFUN([PGAC_C_SIGNED],
 [AC_CACHE_CHECK(for signed types, pgac_cv_c_signed,
-[AC_TRY_COMPILE([],
-[signed char c; signed short s; signed int i;],
+[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([],
+[signed char c; signed short s; signed int i;])],
 [pgac_cv_c_signed=yes],
 [pgac_cv_c_signed=no])])
 if test x"$pgac_cv_c_signed" = xno ; then
@@ -81,7 +81,7 @@ AC_DEFUN([PGAC_TYPE_64BIT_INT],
 [define([Ac_define], [translit([have_$1_64], [a-z *], [A-Z_P])])dnl
 define([Ac_cachevar], [translit([pgac_cv_type_$1_64], [ *], [_p])])dnl
 AC_CACHE_CHECK([whether $1 is 64 bits], [Ac_cachevar],
-[AC_TRY_RUN(
+[AC_RUN_IFELSE([AC_LANG_SOURCE(
 [typedef $1 ac_int64;
 
 /*
@@ -107,7 +107,7 @@ int does_int64_work()
 }
 main() {
   exit(! does_int64_work());
-}],
+}])],
 [Ac_cachevar=yes],
 [Ac_cachevar=no],
 [# If cross-compiling, check the size reported by the compiler and
@@ -169,8 +169,8 @@ fi])# PGAC_TYPE_128BIT_INT
 # Define HAVE_FUNCNAME__FUNC or HAVE_FUNCNAME__FUNCTION accordingly.
 AC_DEFUN([PGAC_C_FUNCNAME_SUPPORT],
 [AC_CACHE_CHECK(for __func__, pgac_cv_funcname_func_support,
-[AC_TRY_COMPILE([#include <stdio.h>],
-[printf("%s\n", __func__);],
+[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([#include <stdio.h>],
+[printf("%s\n", __func__);])],
 [pgac_cv_funcname_func_support=yes],
 [pgac_cv_funcname_func_support=no])])
 if test x"$pgac_cv_funcname_func_support" = xyes ; then
@@ -178,8 +178,8 @@ AC_DEFINE(HAVE_FUNCNAME__FUNC, 1,
           [Define to 1 if your compiler understands __func__.])
 else
 AC_CACHE_CHECK(for __FUNCTION__, pgac_cv_funcname_function_support,
-[AC_TRY_COMPILE([#include <stdio.h>],
-[printf("%s\n", __FUNCTION__);],
+[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([#include <stdio.h>],
+[printf("%s\n", __FUNCTION__);])],
 [pgac_cv_funcname_function_support=yes],
 [pgac_cv_funcname_function_support=no])])
 if test x"$pgac_cv_funcname_function_support" = xyes ; then
@@ -199,8 +199,8 @@ fi])# PGAC_C_FUNCNAME_SUPPORT
 # gcc-style compound expressions to be able to wrap the thing into macros.
 AC_DEFUN([PGAC_C_STATIC_ASSERT],
 [AC_CACHE_CHECK(for _Static_assert, pgac_cv__static_assert,
-[AC_TRY_LINK([],
-[({ _Static_assert(1, "foo"); })],
+[AC_LINK_IFELSE([AC_LANG_PROGRAM([],
+[({ _Static_assert(1, "foo"); })])],
 [pgac_cv__static_assert=yes],
 [pgac_cv__static_assert=no])])
 if test x"$pgac_cv__static_assert" = xyes ; then
@@ -219,8 +219,8 @@ fi])# PGAC_C_STATIC_ASSERT
 # have the former and not the latter.
 AC_DEFUN([PGAC_C_TYPES_COMPATIBLE],
 [AC_CACHE_CHECK(for __builtin_types_compatible_p, pgac_cv__types_compatible,
-[AC_TRY_COMPILE([],
-[ int x; static int y[__builtin_types_compatible_p(__typeof__(x), int)]; ],
+[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([],
+[[ int x; static int y[__builtin_types_compatible_p(__typeof__(x), int)]; ]])],
 [pgac_cv__types_compatible=yes],
 [pgac_cv__types_compatible=no])])
 if test x"$pgac_cv__types_compatible" = xyes ; then
@@ -236,8 +236,9 @@ fi])# PGAC_C_TYPES_COMPATIBLE
 # and define HAVE__BUILTIN_BSWAP32 if so.
 AC_DEFUN([PGAC_C_BUILTIN_BSWAP32],
 [AC_CACHE_CHECK(for __builtin_bswap32, pgac_cv__builtin_bswap32,
-[AC_TRY_COMPILE([static unsigned long int x = __builtin_bswap32(0xaabbccdd);],
-[],
+[AC_COMPILE_IFELSE([AC_LANG_SOURCE(
+[static unsigned long int x = __builtin_bswap32(0xaabbccdd);]
+)],
 [pgac_cv__builtin_bswap32=yes],
 [pgac_cv__builtin_bswap32=no])])
 if test x"$pgac_cv__builtin_bswap32" = xyes ; then
@@ -253,8 +254,9 @@ fi])# PGAC_C_BUILTIN_BSWAP32
 # and define HAVE__BUILTIN_CONSTANT_P if so.
 AC_DEFUN([PGAC_C_BUILTIN_CONSTANT_P],
 [AC_CACHE_CHECK(for __builtin_constant_p, pgac_cv__builtin_constant_p,
-[AC_TRY_COMPILE([static int x; static int y[__builtin_constant_p(x) ? x : 1];],
-[],
+[AC_COMPILE_IFELSE([AC_LANG_SOURCE(
+[[static int x; static int y[__builtin_constant_p(x) ? x : 1];]]
+)],
 [pgac_cv__builtin_constant_p=yes],
 [pgac_cv__builtin_constant_p=no])])
 if test x"$pgac_cv__builtin_constant_p" = xyes ; then
@@ -274,8 +276,8 @@ fi])# PGAC_C_BUILTIN_CONSTANT_P
 # and only a warning instead of an error would be produced.
 AC_DEFUN([PGAC_C_BUILTIN_UNREACHABLE],
 [AC_CACHE_CHECK(for __builtin_unreachable, pgac_cv__builtin_unreachable,
-[AC_TRY_LINK([],
-[__builtin_unreachable();],
+[AC_LINK_IFELSE([AC_LANG_PROGRAM([],
+[__builtin_unreachable();])],
 [pgac_cv__builtin_unreachable=yes],
 [pgac_cv__builtin_unreachable=no])])
 if test x"$pgac_cv__builtin_unreachable" = xyes ; then
@@ -291,10 +293,10 @@ fi])# PGAC_C_BUILTIN_UNREACHABLE
 # and define HAVE__VA_ARGS if so.
 AC_DEFUN([PGAC_C_VA_ARGS],
 [AC_CACHE_CHECK(for __VA_ARGS__, pgac_cv__va_args,
-[AC_TRY_COMPILE([#include <stdio.h>],
+[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([#include <stdio.h>],
 [#define debug(...) fprintf(stderr, __VA_ARGS__)
 debug("%s", "blarg");
-],
+])],
 [pgac_cv__va_args=yes],
 [pgac_cv__va_args=no])])
 if test x"$pgac_cv__va_args" = xyes ; then
@@ -386,10 +388,10 @@ undefine([Ac_cachevar])dnl
 # NB: Some platforms only do 32bit tas, others only do 8bit tas. Test both.
 AC_DEFUN([PGAC_HAVE_GCC__SYNC_CHAR_TAS],
 [AC_CACHE_CHECK(for builtin __sync char locking functions, pgac_cv_gcc_sync_char_tas,
-[AC_TRY_LINK([],
+[AC_LINK_IFELSE([AC_LANG_PROGRAM([],
   [char lock = 0;
    __sync_lock_test_and_set(&lock, 1);
-   __sync_lock_release(&lock);],
+   __sync_lock_release(&lock);])],
   [pgac_cv_gcc_sync_char_tas="yes"],
   [pgac_cv_gcc_sync_char_tas="no"])])
 if test x"$pgac_cv_gcc_sync_char_tas" = x"yes"; then
@@ -402,10 +404,10 @@ fi])# PGAC_HAVE_GCC__SYNC_CHAR_TAS
 # and define HAVE_GCC__SYNC_INT32_TAS
 AC_DEFUN([PGAC_HAVE_GCC__SYNC_INT32_TAS],
 [AC_CACHE_CHECK(for builtin __sync int32 locking functions, pgac_cv_gcc_sync_int32_tas,
-[AC_TRY_LINK([],
+[AC_LINK_IFELSE([AC_LANG_PROGRAM([],
   [int lock = 0;
    __sync_lock_test_and_set(&lock, 1);
-   __sync_lock_release(&lock);],
+   __sync_lock_release(&lock);])],
   [pgac_cv_gcc_sync_int32_tas="yes"],
   [pgac_cv_gcc_sync_int32_tas="no"])])
 if test x"$pgac_cv_gcc_sync_int32_tas" = x"yes"; then
@@ -418,9 +420,9 @@ fi])# PGAC_HAVE_GCC__SYNC_INT32_TAS
 # types, and define HAVE_GCC__SYNC_INT32_CAS if so.
 AC_DEFUN([PGAC_HAVE_GCC__SYNC_INT32_CAS],
 [AC_CACHE_CHECK(for builtin __sync int32 atomic operations, pgac_cv_gcc_sync_int32_cas,
-[AC_TRY_LINK([],
+[AC_LINK_IFELSE([AC_LANG_PROGRAM([],
   [int val = 0;
-   __sync_val_compare_and_swap(&val, 0, 37);],
+   __sync_val_compare_and_swap(&val, 0, 37);])],
   [pgac_cv_gcc_sync_int32_cas="yes"],
   [pgac_cv_gcc_sync_int32_cas="no"])])
 if test x"$pgac_cv_gcc_sync_int32_cas" = x"yes"; then
@@ -433,9 +435,9 @@ fi])# PGAC_HAVE_GCC__SYNC_INT32_CAS
 # types, and define HAVE_GCC__SYNC_INT64_CAS if so.
 AC_DEFUN([PGAC_HAVE_GCC__SYNC_INT64_CAS],
 [AC_CACHE_CHECK(for builtin __sync int64 atomic operations, pgac_cv_gcc_sync_int64_cas,
-[AC_TRY_LINK([],
+[AC_LINK_IFELSE([AC_LANG_PROGRAM([],
   [PG_INT64_TYPE lock = 0;
-   __sync_val_compare_and_swap(&lock, 0, (PG_INT64_TYPE) 37);],
+   __sync_val_compare_and_swap(&lock, 0, (PG_INT64_TYPE) 37);])],
   [pgac_cv_gcc_sync_int64_cas="yes"],
   [pgac_cv_gcc_sync_int64_cas="no"])])
 if test x"$pgac_cv_gcc_sync_int64_cas" = x"yes"; then
@@ -448,10 +450,10 @@ fi])# PGAC_HAVE_GCC__SYNC_INT64_CAS
 # types, and define HAVE_GCC__ATOMIC_INT32_CAS if so.
 AC_DEFUN([PGAC_HAVE_GCC__ATOMIC_INT32_CAS],
 [AC_CACHE_CHECK(for builtin __atomic int32 atomic operations, pgac_cv_gcc_atomic_int32_cas,
-[AC_TRY_LINK([],
+[AC_LINK_IFELSE([AC_LANG_PROGRAM([],
   [int val = 0;
    int expect = 0;
-   __atomic_compare_exchange_n(&val, &expect, 37, 0, __ATOMIC_SEQ_CST, __ATOMIC_RELAXED);],
+   __atomic_compare_exchange_n(&val, &expect, 37, 0, __ATOMIC_SEQ_CST, __ATOMIC_RELAXED);])],
   [pgac_cv_gcc_atomic_int32_cas="yes"],
   [pgac_cv_gcc_atomic_int32_cas="no"])])
 if test x"$pgac_cv_gcc_atomic_int32_cas" = x"yes"; then
@@ -464,10 +466,10 @@ fi])# PGAC_HAVE_GCC__ATOMIC_INT32_CAS
 # types, and define HAVE_GCC__ATOMIC_INT64_CAS if so.
 AC_DEFUN([PGAC_HAVE_GCC__ATOMIC_INT64_CAS],
 [AC_CACHE_CHECK(for builtin __atomic int64 atomic operations, pgac_cv_gcc_atomic_int64_cas,
-[AC_TRY_LINK([],
+[AC_LINK_IFELSE([AC_LANG_PROGRAM([],
   [PG_INT64_TYPE val = 0;
    PG_INT64_TYPE expect = 0;
-   __atomic_compare_exchange_n(&val, &expect, 37, 0, __ATOMIC_SEQ_CST, __ATOMIC_RELAXED);],
+   __atomic_compare_exchange_n(&val, &expect, 37, 0, __ATOMIC_SEQ_CST, __ATOMIC_RELAXED);])],
   [pgac_cv_gcc_atomic_int64_cas="yes"],
   [pgac_cv_gcc_atomic_int64_cas="no"])])
 if test x"$pgac_cv_gcc_atomic_int64_cas" = x"yes"; then
@@ -490,10 +492,10 @@ AC_CACHE_CHECK([for _mm_crc32_u8 and _mm_crc32_u32 with CFLAGS=$1], [Ac_cachevar
 CFLAGS="$pgac_save_CFLAGS $1"
 ac_save_c_werror_flag=$ac_c_werror_flag
 ac_c_werror_flag=yes
-AC_TRY_LINK([#include <nmmintrin.h>],
+AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <nmmintrin.h>],
   [unsigned int crc = 0;
    crc = _mm_crc32_u8(crc, 0);
-   crc = _mm_crc32_u32(crc, 0);],
+   crc = _mm_crc32_u32(crc, 0);])],
   [Ac_cachevar=yes],
   [Ac_cachevar=no])
 ac_c_werror_flag=$ac_save_c_werror_flag
diff --git a/config/c-library.m4 b/config/c-library.m4
index 933d95e8efa..7b1d9f4063d 100644
--- a/config/c-library.m4
+++ b/config/c-library.m4
@@ -8,13 +8,13 @@
 # HAVE_INT_TIMEZONE.
 AC_DEFUN([PGAC_VAR_INT_TIMEZONE],
 [AC_CACHE_CHECK(for int timezone, pgac_cv_var_int_timezone,
-[AC_TRY_LINK([#include <time.h>
+[AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <time.h>
 int res;],
   [#ifndef __CYGWIN__
 res = timezone / 60;
 #else
 res = _timezone / 60;
-#endif],
+#endif])],
   [pgac_cv_var_int_timezone=yes],
   [pgac_cv_var_int_timezone=no])])
 if test x"$pgac_cv_var_int_timezone" = xyes ; then
@@ -41,13 +41,13 @@ if test "$ac_cv_member_struct_tm_tm_zone" = yes; then
              `HAVE_STRUCT_TM_TM_ZONE' instead.])
 fi
 AC_CACHE_CHECK(for tzname, ac_cv_var_tzname,
-[AC_TRY_LINK(
-[#include <time.h>
+[AC_LINK_IFELSE([AC_LANG_PROGRAM(
+[[#include <time.h>
 #ifndef tzname /* For SGI.  */
 extern char *tzname[]; /* RS6000 and others reject char **tzname.  */
 #endif
-],
-[atoi(*tzname);], ac_cv_var_tzname=yes, ac_cv_var_tzname=no)])
+]],
+[atoi(*tzname);])], ac_cv_var_tzname=yes, ac_cv_var_tzname=no)])
 if test $ac_cv_var_tzname = yes; then
     AC_DEFINE(HAVE_TZNAME, 1,
               [Define to 1 if you have the external array `tzname'.])
@@ -62,10 +62,10 @@ fi
 AC_DEFUN([PGAC_FUNC_GETTIMEOFDAY_1ARG],
 [AC_CACHE_CHECK(whether gettimeofday takes only one argument,
 pgac_cv_func_gettimeofday_1arg,
-[AC_TRY_COMPILE([#include <sys/time.h>],
+[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([#include <sys/time.h>],
 [struct timeval *tp;
 struct timezone *tzp;
-gettimeofday(tp,tzp);],
+gettimeofday(tp,tzp);])],
 [pgac_cv_func_gettimeofday_1arg=no],
 [pgac_cv_func_gettimeofday_1arg=yes])])
 if test x"$pgac_cv_func_gettimeofday_1arg" = xyes ; then
@@ -86,13 +86,13 @@ AH_VERBATIM(GETTIMEOFDAY_1ARG_,
 AC_DEFUN([PGAC_FUNC_STRERROR_R_INT],
 [AC_CACHE_CHECK(whether strerror_r returns int,
 pgac_cv_func_strerror_r_int,
-[AC_TRY_COMPILE([#include <string.h>],
+[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([#include <string.h>],
 [#ifndef _AIX
 int strerror_r(int, char *, size_t);
 #else
 /* Older AIX has 'int' for the third argument so we don't test the args. */
 int strerror_r();
-#endif],
+#endif])],
 [pgac_cv_func_strerror_r_int=yes],
 [pgac_cv_func_strerror_r_int=no])])
 if test x"$pgac_cv_func_strerror_r_int" = xyes ; then
@@ -181,12 +181,12 @@ AC_DEFUN([PGAC_STRUCT_ADDRINFO],
 # a fancier check.
 AC_DEFUN([PGAC_FUNC_POSIX_SIGNALS],
 [AC_CACHE_CHECK(for POSIX signal interface, pgac_cv_func_posix_signals,
-[AC_TRY_LINK([#include <signal.h>
+[AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <signal.h>
 ],
 [struct sigaction act, oact;
 sigemptyset(&act.sa_mask);
 act.sa_flags = SA_RESTART;
-sigaction(0, &act, &oact);],
+sigaction(0, &act, &oact);])],
 [pgac_cv_func_posix_signals=yes],
 [pgac_cv_func_posix_signals=no])])
 if test x"$pgac_cv_func_posix_signals" = xyes ; then
@@ -210,7 +210,7 @@ AC_DEFUN([PGAC_FUNC_SNPRINTF_LONG_LONG_INT_MODIFIER],
 [AC_MSG_CHECKING([snprintf length modifier for long long int])
 AC_CACHE_VAL(pgac_cv_snprintf_long_long_int_modifier,
 [for pgac_modifier in 'll' 'q' 'I64'; do
-AC_TRY_RUN([#include <stdio.h>
+AC_RUN_IFELSE([AC_LANG_SOURCE([[#include <stdio.h>
 typedef long long int ac_int64;
 #define INT64_FORMAT "%${pgac_modifier}d"
 
@@ -233,7 +233,7 @@ int does_int64_snprintf_work()
 }
 main() {
   exit(! does_int64_snprintf_work());
-}],
+}]])],
 [pgac_cv_snprintf_long_long_int_modifier=$pgac_modifier; break],
 [],
 [pgac_cv_snprintf_long_long_int_modifier=cross; break])
@@ -259,7 +259,7 @@ esac])# PGAC_FUNC_SNPRINTF_LONG_LONG_INT_MODIFIER
 AC_DEFUN([PGAC_FUNC_SNPRINTF_ARG_CONTROL],
 [AC_MSG_CHECKING([whether snprintf supports argument control])
 AC_CACHE_VAL(pgac_cv_snprintf_arg_control,
-[AC_TRY_RUN([#include <stdio.h>
+[AC_RUN_IFELSE([AC_LANG_SOURCE([[#include <stdio.h>
 #include <string.h>
 
 int main()
@@ -271,7 +271,7 @@ int main()
   if (strcmp(buf, "4 3") != 0)
     return 1;
   return 0;
-}],
+}]])],
 [pgac_cv_snprintf_arg_control=yes],
 [pgac_cv_snprintf_arg_control=no],
 [pgac_cv_snprintf_arg_control=cross])
@@ -288,7 +288,7 @@ AC_MSG_RESULT([$pgac_cv_snprintf_arg_control])
 AC_DEFUN([PGAC_FUNC_SNPRINTF_SIZE_T_SUPPORT],
 [AC_MSG_CHECKING([whether snprintf supports the %z modifier])
 AC_CACHE_VAL(pgac_cv_snprintf_size_t_support,
-[AC_TRY_RUN([#include <stdio.h>
+[AC_RUN_IFELSE([AC_LANG_SOURCE([[#include <stdio.h>
 #include <string.h>
 
 int main()
@@ -308,7 +308,7 @@ int main()
   if (strcmp(bufz, buf64) != 0)
     return 1;
   return 0;
-}],
+}]])],
 [pgac_cv_snprintf_size_t_support=yes],
 [pgac_cv_snprintf_size_t_support=no],
 [pgac_cv_snprintf_size_t_support=cross])
diff --git a/config/programs.m4 b/config/programs.m4
index ed6711df167..7ac948d4fd3 100644
--- a/config/programs.m4
+++ b/config/programs.m4
@@ -200,14 +200,14 @@ fi
 
 AC_DEFUN([PGAC_VAR_RL_COMPLETION_APPEND_CHARACTER],
 [AC_CACHE_CHECK([for rl_completion_append_character], pgac_cv_var_rl_completion_append_character,
-[AC_TRY_LINK([#include <stdio.h>
+[AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <stdio.h>
 #ifdef HAVE_READLINE_READLINE_H
 # include <readline/readline.h>
 #elif defined(HAVE_READLINE_H)
 # include <readline.h>
 #endif
 ],
-[rl_completion_append_character = 'x';],
+[rl_completion_append_character = 'x';])],
 [pgac_cv_var_rl_completion_append_character=yes],
 [pgac_cv_var_rl_completion_append_character=no])])
 if test x"$pgac_cv_var_rl_completion_append_character" = x"yes"; then