* Use AC_TRY_LINK instead of AC_TRY_cOMPILE to see if the compiler hints

for prefetch and branch prediction work.  A non-happy compiler could
  just think these were functions and we wouldn't get the error, because
  we didn't try to link.

  Refs trac:287

This commit was SVN r11333.

The following Trac tickets were found above:
  Ticket 287 --> https://svn.open-mpi.org/trac/ompi/ticket/287

config/ompi_setup_cc.m4

@@ -202,7 +202,7 @@ AC_DEFUN([OMPI_SETUP_CC],[
     # see if the C compiler supports __builtin_expect
     AC_CACHE_CHECK([if $CC supports __builtin_expect],
         [ompi_cv_cc_supports___builtin_expect],
-        [AC_TRY_COMPILE([],
+        [AC_TRY_LINK([],
           [void *ptr = (void*) 0;
            if (__builtin_expect (ptr != (void*) 0, 1)) return 0;],
           [ompi_cv_cc_supports___builtin_expect="yes"],
@@ -218,7 +218,7 @@ AC_DEFUN([OMPI_SETUP_CC],[
     # see if the C compiler supports __builtin_prefetch
     AC_CACHE_CHECK([if $CC supports __builtin_prefetch],
         [ompi_cv_cc_supports___builtin_prefetch],
-        [AC_TRY_COMPILE([],
+        [AC_TRY_LINK([],
           [int ptr;
            __builtin_prefetch(&ptr,0,0);],
           [ompi_cv_cc_supports___builtin_prefetch="yes"],

config/ompi_setup_cxx.m4

@@ -137,7 +137,7 @@ AC_DEFUN([OMPI_SETUP_CXX],[
     AC_LANG_PUSH(C++)
     AC_CACHE_CHECK([if $CXX supports __builtin_expect],
         [ompi_cv_cxx_supports___builtin_expect],
-        [AC_TRY_COMPILE([],
+        [AC_TRY_LINK([],
           [void *ptr = (void*) 0;
            if (__builtin_expect (ptr != (void*) 0, 1)) return 0;],
           [ompi_cv_cxx_supports___builtin_expect="yes"],
@@ -155,7 +155,7 @@ AC_DEFUN([OMPI_SETUP_CXX],[
     AC_LANG_PUSH(C++)
     AC_CACHE_CHECK([if $CXX supports __builtin_prefetch],
         [ompi_cv_cxx_supports___builtin_prefetch],
-        [AC_TRY_COMPILE([],
+        [AC_TRY_LINK([],
           [int ptr;
            __builtin_prefetch(&ptr,0,0);],
           [ompi_cv_cxx_supports___builtin_prefetch="yes"],