m4: update to autoconf-archive 20140228

m4/ax_check_link_flag.m4

@@ -4,7 +4,7 @@
 #
 # SYNOPSIS
 #
-#   AX_CHECK_LINK_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS])
+#   AX_CHECK_LINK_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS], [INPUT])
 #
 # DESCRIPTION
 #
@@ -19,6 +19,8 @@
 #   EXTRA-FLAGS FLAG".  This can for example be used to force the linker to
 #   issue an error when a bad flag is given.
 #
+#   INPUT gives an alternative input source to AC_LINK_IFELSE.
+#
 #   NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. Please keep this
 #   macro in sync with AX_CHECK_{PREPROC,COMPILE}_FLAG.
 #
@@ -53,14 +55,14 @@
 #   modified version of the Autoconf Macro, you may extend this special
 #   exception to the GPL to apply to your modified version as well.
 
-#serial 2
+#serial 3
 
 AC_DEFUN([AX_CHECK_LINK_FLAG],
 [AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_ldflags_$4_$1])dnl
 AC_CACHE_CHECK([whether the linker accepts $1], CACHEVAR, [
   ax_check_save_flags=$LDFLAGS
   LDFLAGS="$LDFLAGS $4 $1"
-  AC_LINK_IFELSE([AC_LANG_PROGRAM()],
+  AC_LINK_IFELSE([m4_default([$5],[AC_LANG_PROGRAM()])],
     [AS_VAR_SET(CACHEVAR,[yes])],
     [AS_VAR_SET(CACHEVAR,[no])])
   LDFLAGS=$ax_check_save_flags])