Hi!
The .count.NN vars have TREE_NO_WARNING set on them, because
they may be uninitialized if the loop body isn't executed at all
(zero trip count), but copy_var_decl wasn't propagating the flag over to
the parallel body ompfn function vars.
Fixed thusly, tested on x86_64-linux, committed to trunk/4.8.
2013-08-28 Jakub Jelinek <ja...@redhat.com>
PR middle-end/58257
* omp-low.c (copy_var_decl): Copy over TREE_NO_WARNING flag.
* c-c++-common/gomp/pr58257.c: New test.
--- gcc/omp-low.c.jj 2013-08-28 11:27:54.000000000 +0200
+++ gcc/omp-low.c 2013-08-28 11:39:07.578948737 +0200
@@ -850,6 +850,7 @@ copy_var_decl (tree var, tree name, tree
DECL_ARTIFICIAL (copy) = DECL_ARTIFICIAL (var);
DECL_IGNORED_P (copy) = DECL_IGNORED_P (var);
DECL_CONTEXT (copy) = DECL_CONTEXT (var);
+ TREE_NO_WARNING (copy) = TREE_NO_WARNING (var);
TREE_USED (copy) = 1;
DECL_SEEN_IN_BIND_EXPR_P (copy) = 1;
--- gcc/testsuite/c-c++-common/gomp/pr58257.c.jj 2013-08-28
11:56:17.991343584 +0200
+++ gcc/testsuite/c-c++-common/gomp/pr58257.c 2013-08-28 11:58:24.616648066
+0200
@@ -0,0 +1,15 @@
+/* PR middle-end/58257 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fopenmp -Wall" } */
+
+int
+foo (int n)
+{
+ int a[10][10];
+ int x, y;
+#pragma omp parallel for collapse(2) /* { dg-bogus "may be used
uninitialized in this function" } */
+ for (x = 0; x < n; x++) /* { dg-bogus "may be used
uninitialized in this function" } */
+ for (y = 0; y < n; y++)
+ a[x][y] = x + y * y;
+ return a[0][0];
+}
Jakub
