backport: re PR target/84772 (powerpc-spe: Spurious "is used uninitialized" warning...

	Backported from mainline
	2018-03-09  Jakub Jelinek  <jakub@redhat.com>

	PR target/84772
	* config/rs6000/rs6000.c (rs6000_gimplify_va_arg): Mark va_arg_tmp
	temporary TREE_ADDRESSABLE before gimplification of BUILT_IN_MEMCPY.

	* gcc.dg/pr84772.c: New test.

From-SVN: r261918

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index f00be0c914b4c3572da122fdfb9d41730fa406f0..5b4c831735859380cc0465d11a9a225243bc8273 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -3,6 +3,10 @@
        Backported from mainline
        2018-03-09  Jakub Jelinek  <jakub@redhat.com>
 
+       PR target/84772
+       * config/rs6000/rs6000.c (rs6000_gimplify_va_arg): Mark va_arg_tmp
+       temporary TREE_ADDRESSABLE before gimplification of BUILT_IN_MEMCPY.
+
        PR c++/84767
        * tree-inline.c (copy_tree_body_r): For INDIRECT_REF of a remapped
        decl, use remap_type if we want to use the type.

diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 01ae6ad8787cc353d446c58485849ea1ba44f0d2..0797c16b120e00a7063f06cc51909dac0f2b5bcb 100644 (file)
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -14124,6 +14124,7 @@ rs6000_gimplify_va_arg (tree valist, tree type, gimple_seq *pre_p,
 
       tree copy = build_call_expr (builtin_decl_implicit (BUILT_IN_MEMCPY),
                                   3, dest_addr, addr, size_int (rsize * 4));
+      TREE_ADDRESSABLE (tmp) = 1;
 
       gimplify_and_add (copy, pre_p);
       addr = dest_addr;

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index e464c19ad356a6f785e11881cc0780814e1e77ea..9d78f627a155f1b9e525dddd571e071bcb7c9d05 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,6 +1,11 @@
 2018-06-22  Jakub Jelinek  <jakub@redhat.com>
 
        Backported from mainline
+       2018-03-09  Jakub Jelinek  <jakub@redhat.com>
+
+       PR target/84772
+       * gcc.dg/pr84772.c: New test.
+
        2018-03-09  Jason Merrill  <jason@redhat.com>
                    Jakub Jelinek  <jakub@redhat.com>
 

diff --git a/gcc/testsuite/gcc.dg/pr84772.c b/gcc/testsuite/gcc.dg/pr84772.c
new file mode 100644 (file)
index 0000000..1241d21
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr84772.c
@@ -0,0 +1,13 @@
+/* PR target/84772 */
+/* { dg-do compile } */
+/* { dg-options "-O -Wuninitialized" } */
+
+#include <stdarg.h>
+
+void
+foo (int *x, int y, va_list ap)
+{
+  __builtin_memset (x, 0, sizeof (int));
+  for (int i = 0; i < y; i++)
+    va_arg (ap, long double);                  /* { dg-bogus "uninitialized" } */  
+}