Change test from using AC_TRY_RUN to using AC_RUN_IFELSE so we can

automatically pick up stdint.h by using AC_INCLUDES_DEFAULT.  This is needed
for the types like int8_t which were added last week.

This commit was SVN r21721.

config/c_get_alignment.m4

@@ -24,21 +24,16 @@ dnl
 AC_DEFUN([OMPI_C_GET_ALIGNMENT],[
     AC_CACHE_CHECK([alignment of $1],
                    [AS_TR_SH([ompi_cv_c_align_$1])],
-                   [AC_TRY_RUN([
-#include <stddef.h>
-#include <stdio.h>
-#include <stdlib.h>
-struct foo { char c; $1 x; };
-int main(int argc, char * argv[])
-{
+		   [AC_RUN_IFELSE([AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT],
+[[
+    struct foo { char c; $1 x; };
     struct foo *p = (struct foo *) malloc(sizeof(struct foo));
     int diff;
     FILE *f=fopen("conftestval", "w");
     if (!f) exit(1);
     diff = ((char *)&p->x) - ((char *)&p->c);
     fprintf(f, "%d\n", (diff >= 0) ? diff : -diff);
-    return 0;
-}],                            [AS_TR_SH([ompi_cv_c_align_$1])=`cat conftestval`],
+]])],                         [AS_TR_SH([ompi_cv_c_align_$1])=`cat conftestval`],
                                [AC_MSG_WARN([*** Problem running configure test!])
                                 AC_MSG_WARN([*** See config.log for details.])
                                 AC_MSG_ERROR([*** Cannot continue.])],