PR middle-end/79221 - missing -Wstringop-overflow= on a strcat overflow

gcc/testsuite/ChangeLog:
	* gcc.dg/Wstringop-overflow-26.c: New test.

From-SVN: r279227

gcc/testsuite/ChangeLog

+2019-12-11  Martin Sebor  <msebor@redhat.com>
+
+	PR middle-end/79221
+	* gcc.dg/Wstringop-overflow-26.c: New test.
+
 2019-12-11  Andre Vieira  <andre.simoesdiasvieira@arm.com>
 
 	* gcc.dg/vect/vect-epilogues.c: Remove xfail for arm.

gcc/testsuite/gcc.dg/Wstringop-overflow-26.c

+/* PR middle-end/79221 - missing -Wstringop-overflow= on a strcat overflow
+   { dg-do compile }
+   { dg-options "-O2 -Wall" } */
+
+extern char* strcat (char*, const char*);
+
+char d[3];
+
+void f (int i)
+{
+  const char *s = i < 0 ? "01234567" : "89abcd";
+  strcat (d, s);    // { dg-warning "'strcat' writing between 7 and 9 bytes into a region of size 3" } */
+}
+
+
+void g (int i)
+{
+  const char *s = i < 0 ? "12345678" : "87654321";
+  strcat (d, s);    // { dg-warning "\\\[-Warray-bounds|-Wstringop-overflow" }
+}