invoke.texi (Warning Options): Add -Wmemset-elt-size.

	* doc/invoke.texi (Warning Options): Add -Wmemset-elt-size.
	(-Wmemset-elt-size): New item.
c-family/
	* c.opt (Wmemset-elt-size): New option.
	* c-common.c (warn_for_memset): New function.
	* c-common.h (warn_for_memset): Declare.
c/
	* c-parser.c (c_parser_postfix_expression_after_primary): Call
	warn_for_memset instead of warning directly here.
cp/
	* parser.c (cp_parser_postfix_expression): Call
	warn_for_memset instead of warning directly here.
testsuite/
	* c-c++-common/memset-array.c: New test.

From-SVN: r235475

1 files changed, 36 insertions, 0 deletions

diff --git a/gcc/testsuite/c-c++-common/memset-array.c b/gcc/testsuite/c-c++-common/memset-array.c
new file mode 100644
index 0000000..0346a21
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/memset-array.c
@@ -0,0 +1,36 @@
+/* { dg-do compile } */
+/* { dg-options "-Wmemset-elt-size" } */
+enum a {
+  a_1,
+  a_2,
+  a_n
+};
+int t1[20];
+int t2[a_n];
+
+struct s
+{
+  int t[20];
+};
+
+void foo (struct s *s)
+{
+  __builtin_memset (t1, 0, 20); /* { dg-warning "element size" } */
+  __builtin_memset (t2, 0, a_n); /* { dg-warning "element size" } */
+  __builtin_memset (s->t, 0, 20); /* { dg-warning "element size" } */
+}
+
+char u1[20];
+char u2[a_n];
+
+struct s2
+{
+  char u[20];
+};
+
+void bar (struct s2 *s)
+{
+  __builtin_memset (u1, 0, 20);
+  __builtin_memset (u2, 0, a_n);
+  __builtin_memset (s->u, 0, 20);
+}