AIX: Test the -qlonglong option before use.

xlc provides "long long" unconditionally at C99-compatible language
levels, and this option provokes a warning.  The warning interferes with
"configure" tests that fail in response to any warning.  Notably, before
commit 85a2a8903f, it interfered with the
test for -qnoansialias.  Back-patch to 9.0 (all supported versions).

configure

@@ -4459,6 +4459,56 @@ sed 's/^/| /' conftest.$ac_ext >&5
 $as_echo "no" >&6; }
 fi
 
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+
+  { $as_echo "$as_me:$LINENO: checking if $CC supports -qlonglong" >&5
+$as_echo_n "checking if $CC supports -qlonglong... " >&6; }
+pgac_save_CFLAGS=$CFLAGS
+CFLAGS="$pgac_save_CFLAGS -qlonglong"
+cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext
+if { (ac_try="$ac_compile"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval ac_try_echo="\"\$as_me:$LINENO: $ac_try_echo\""
+$as_echo "$ac_try_echo") >&5
+  (eval "$ac_compile") 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && {
+	 test -z "$ac_c_werror_flag" ||
+	 test ! -s conftest.err
+       } && test -s conftest.$ac_objext; then
+  { $as_echo "$as_me:$LINENO: result: yes" >&5
+$as_echo "yes" >&6; }
+else
+  $as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+	CFLAGS="$pgac_save_CFLAGS"
+                    { $as_echo "$as_me:$LINENO: result: no" >&5
+$as_echo "no" >&6; }
+fi
+
 rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
 
 fi

configure.in

@@ -447,6 +447,7 @@ elif test "$ICC" = yes; then
 elif test "$PORTNAME" = "aix"; then
   # AIX's xlc has to have strict aliasing turned off too
   PGAC_PROG_CC_CFLAGS_OPT([-qnoansialias])
+  PGAC_PROG_CC_CFLAGS_OPT([-qlonglong])
 fi
 
 # supply -g if --enable-debug

src/template/aix

@@ -7,7 +7,7 @@ if test "$GCC" != yes ; then
       CFLAGS="-O -qmaxmem=16384 -qsrcmsg"
       ;;
     *)
-      CFLAGS="-O2 -qmaxmem=16384 -qsrcmsg -qlonglong"
+      CFLAGS="-O2 -qmaxmem=16384 -qsrcmsg"
       ;;
   esac
 fi