On Mon, 8 Jun 2015, Marek Polacek wrote:
> This PR is about a bogus -Wunused-variable warning about an internal
> structure (*.Lubsan_data*), exposed by the debug-early merge.
>
> I think the "defined but not used" warning should not be allowed for
> the compiler-generated entities.
>
> Bootstrapped/regtested on x86_64-linux, ok for trunk?
Ok.
Thanks,
Richard.
> 2015-06-08 Marek Polacek
>
> PR sanitizer/66452
> * toplev.c (check_global_declaration): Don't warn about artificial
> decls.
>
> * g++.dg/ubsan/pr66452.C: New test.
>
> diff --git gcc/testsuite/g++.dg/ubsan/pr66452.C
> gcc/testsuite/g++.dg/ubsan/pr66452.C
> index e69de29..473543c 100644
> --- gcc/testsuite/g++.dg/ubsan/pr66452.C
> +++ gcc/testsuite/g++.dg/ubsan/pr66452.C
> @@ -0,0 +1,16 @@
> +// PR sanitizer/66452
> +// { dg-do compile }
> +// { dg-options "-Wall -fsanitize=undefined" }
> +
> +class A {
> +public:
> + A(int);
> +};
> +class B {
> + A m_fn1() const;
> +};
> +A B::m_fn1() const {
> + for (int i = 0;i;)
> +;
> + return 0;
> +}
> diff --git gcc/toplev.c gcc/toplev.c
> index fd2ac4e..eb8b8ac 100644
> --- gcc/toplev.c
> +++ gcc/toplev.c
> @@ -534,6 +534,7 @@ check_global_declaration (tree decl)
>to handle multiple external decls in different scopes. */
>&& ! (DECL_NAME (decl) && TREE_USED (DECL_NAME (decl)))
>&& ! DECL_EXTERNAL (decl)
> + && ! DECL_ARTIFICIAL (decl)
>&& ! TREE_PUBLIC (decl)
>/* A volatile variable might be used in some non-obvious way. */
>&& ! TREE_THIS_VOLATILE (decl)
>
> Marek
>
>
--
Richard Biener
SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Dilip Upmanyu, Graham
Norton, HRB 21284 (AG Nuernberg)
