PR middle-end/78138 - missing warnings on buffer overflow with non-constant source length

gcc/testsuite/ChangeLog:

	PR middle-end/78138
	* gcc.dg/pr78138.c: New test.

From-SVN: r244297

gcc/testsuite/ChangeLog

+2017-01-10  Martin Sebor  <msebor@redhat.com>
+
+	PR middle-end/78138
+	* gcc.dg/pr78138.c: New test. 
+
 2017-01-10  David Malcolm  <dmalcolm@redhat.com>
 
 	PR c++/77949

gcc/testsuite/gcc.dg/pr78138.c

+/* PR middle-end/78138 - missing warnings on buffer overflow with non-constant
+   source length
+   { dg-do compile }
+   { dg-options "-O2 -Wformat-length" } */
+
+char d [5];
+
+void* memcpy (void*, const void*, unsigned long);
+extern char* strcpy (char*, const char*);
+
+void f (int i, int j)
+{
+  strcpy (d, j ? "12345" : "123456");   /* { dg-warning ".strcpy. writing 6 bytes into a region of size 5" } */
+}
+
+void g (void *p)
+{
+  extern unsigned n;
+  if (n < 17 || 32 < n) n = 7;
+
+  memcpy (d, p, n);   /* { dg-warning ".memcpy.: writing between 7 and 32 bytes into a region of size 5" } */
+};