Don't parallelize loops if libgomp not supported

2016-01-11  Tom de Vries  <tom@codesourcery.com>

	PR tree-optimization/69058
	* tree-parloops.c (pass_parallelize_loops::execute): Return 0 if libgomp
	not supported.

From-SVN: r232208

gcc/ChangeLog

+2016-01-11  Tom de Vries  <tom@codesourcery.com>
+
+	PR tree-optimization/69058
+	* tree-parloops.c (pass_parallelize_loops::execute): Return 0 if libgomp
+	not supported.
+
 2016-01-11  Andrew Burgess  <andrew.burgess@embecosm.com>
 
 	* config/arc/arc.opt (mdiv-rem): Add period to the end.

gcc/tree-parloops.c

@@ -2836,6 +2836,10 @@ pass_parallelize_loops::execute (function *fun)
   if (number_of_loops (fun) <= 1)
     return 0;
 
+  tree nthreads = builtin_decl_explicit (BUILT_IN_OMP_GET_NUM_THREADS);
+  if (nthreads == NULL_TREE)
+    return 0;
+
   if (parallelize_loops ())
     {
       fun->curr_properties &= ~(PROP_gimple_eomp);