1 files changed, 79 insertions, 0 deletions
diff --git a/gcc/testsuite/gcc.dg/warn-addr-cmp.c b/gcc/testsuite/gcc.dg/warn-addr-cmp.c
new file mode 100644
index 000000000..07491d1bb
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/warn-addr-cmp.c
@@ -0,0 +1,79 @@
+/* { dg-do compile } */
+/* { dg-require-weak "" } */
+/* { dg-options "-Waddress" } */
+/* Warning when addr convert to bool always gives known result.
+   Ada/Pascal programmers sometimes write 0-param functions without
+   (), and might as well warn on variables, too.  */
+
+int func (void);
+extern int var;
+int weak_func (void) __attribute__ ((weak));
+extern int weak_var __attribute__ ((weak));
+
+int
+test_func_cmp (void)
+{
+  if (func)      /* { dg-warning "the address of 'func'" } */
+    return 1;
+  if (!func)     /* { dg-warning "the address of 'func'" } */
+    return 1;
+  if (&var)     /* { dg-warning "the address of 'var'" } */
+    return 1;
+  if (!&var)     /* { dg-warning "the address of 'var'" } */
+    return 1;
+  if (weak_func)
+    return 1;
+  if (!weak_func)
+    return 1;
+  if (&weak_var)
+    return 1;
+  if (!&weak_var)
+    return 1;
+  return 0;
+}
+
+/* Test equality with 0 on the right hand side.  */
+int
+test_func_cmp_rhs_zero (void)
+{
+  if (func == 0)     /* { dg-warning "the comparison will always evaluate as 'false'" } */
+    return 1;
+  if (func != 0)     /* { dg-warning "the comparison will always evaluate as 'true'" } */
+    return 1;
+  if (&var == 0)     /* { dg-warning "the comparison will always evaluate as 'false'" } */
+    return 1;
+  if (&var != 0)     /* { dg-warning "the comparison will always evaluate as 'true'" } */
+    return 1;
+  if (weak_func == 0)
+    return 1;
+  if (weak_func != 0)
+    return 1;
+  if (&weak_var == 0)
+    return 1;
+  if (&weak_var != 0)
+    return 1;
+  return 0;
+}
+
+/* Test equality with 0 on the left hand side.  */
+int
+test_func_cmp_lhs_zero (void)
+{
+  if (0 == func)     /* { dg-warning "the comparison will always evaluate as 'false'" } */
+    return 1;
+  if (0 != func)     /* { dg-warning "the comparison will always evaluate as 'true'" } */
+    return 1;
+  if (0 == &var)     /* { dg-warning "the comparison will always evaluate as 'false'" } */
+    return 1;
+  if (0 != &var)     /* { dg-warning "the comparison will always evaluate as 'true'" } */
+    return 1;
+  if (0 == weak_func)
+    return 1;
+  if (0 != weak_func)
+    return 1;
+  if (0 == &weak_var)
+    return 1;
+  if (0 != &weak_var)
+    return 1;
+  return 0;
+}