Hi!
On Wed, Jan 27, 2016 at 11:17:18AM +0100, Richard Biener wrote:
> No, simply warn and set TREE_NO_WARNING so cgraph doesn't warn again.
This seems to work too, bootstrapped/regtested on x86_64-linux and
i686-linux, ok for trunk?
2016-01-25 Jakub Jelinek <ja...@redhat.com>
PR debug/66869
* c-decl.c (c_write_global_declarations_1): Warn with
warn_unused_function if static prototype without definition
is not C_DECL_USED.
* gcc.dg/pr66869.c: New test.
--- gcc/c/c-decl.c.jj 2016-01-25 22:33:11.813025064 +0100
+++ gcc/c/c-decl.c 2016-01-27 13:03:15.896068387 +0100
@@ -10741,11 +10741,22 @@ c_write_global_declarations_1 (tree glob
if (TREE_CODE (decl) == FUNCTION_DECL
&& DECL_INITIAL (decl) == 0
&& DECL_EXTERNAL (decl)
- && !TREE_PUBLIC (decl)
- && C_DECL_USED (decl))
+ && !TREE_PUBLIC (decl))
{
- pedwarn (input_location, 0, "%q+F used but never defined", decl);
- TREE_NO_WARNING (decl) = 1;
+ if (C_DECL_USED (decl))
+ {
+ pedwarn (input_location, 0, "%q+F used but never defined", decl);
+ TREE_NO_WARNING (decl) = 1;
+ }
+ /* For -Wunused-function warn about unused static prototypes. */
+ else if (warn_unused_function
+ && ! DECL_ARTIFICIAL (decl)
+ && ! TREE_NO_WARNING (decl))
+ {
+ warning (OPT_Wunused_function,
+ "%q+F declared %<static%> but never defined", decl);
+ TREE_NO_WARNING (decl) = 1;
+ }
}
wrapup_global_declaration_1 (decl);
--- gcc/testsuite/gcc.dg/pr66869.c.jj 2016-01-27 12:59:46.997929005 +0100
+++ gcc/testsuite/gcc.dg/pr66869.c 2016-01-27 12:59:46.997929005 +0100
@@ -0,0 +1,6 @@
+/* PR debug/66869 */
+/* { dg-do compile } */
+/* { dg-options "-Wunused-function" } */
+
+static void test (void); /* { dg-warning "'test' declared 'static' but never
defined" } */
+int i;
Jakub
