On Tue, 16 May 2017, Marek Polacek wrote:
> Martin L. asked me to have a look at this ICE with ASAN. This is an ICE with
> a
> compound literal in a switch. A hash map gimplify_ctxp->live_switch_vars is
> filled when processing DECL_EXPRs with their DECL_EXPR_DECLs. Such decls
> should
> then be removed from the hash map when gimplifying a BIND_EXPR.
>
> In C, non-static compound literals aren't pushed into any scope, so they were
> never found by gimplify_bind_expr, so they stayed in the hash map resulting in
> a crash on
> 2299 if (gimplify_ctxp->live_switch_vars)
> 2300 {
> 2301 gcc_assert (gimplify_ctxp->live_switch_vars->elements () ==
> 0);
> 2302 delete gimplify_ctxp->live_switch_vars;
> 2303 }
>
> We don't add artificial decls to the hash map:
> 1647 if (!DECL_ARTIFICIAL (decl) &&
> gimplify_ctxp->live_switch_vars)
> 1648 gimplify_ctxp->live_switch_vars->add (decl);
>
> build_compound_literal only marks a decl of a compound literal as artificial
> when the compound literal is static. I think there's no harm in marking
> decls of non-static compound literals as artificial, too (provided it's fine
> to
> skip asan instrumentation of compound literals).
But probably DECL_IGNORED_P as well at the same time?
> Bootstrapped/regtested on x86_64-linux, ok for trunk?
Ok with moving that as well (and re-testing).
Thanks,
Richard.
> 2017-05-16 Marek Polacek <pola...@redhat.com>
>
> PR sanitizer/80659
> * c-decl.c (build_compound_literal): Set DECL_ARTIFICIAL even for
> non-static compound literals.
>
> * gcc.dg/asan/pr80659.c: New test.
>
> diff --git gcc/c/c-decl.c gcc/c/c-decl.c
> index b779d37..887e95d 100644
> --- gcc/c/c-decl.c
> +++ gcc/c/c-decl.c
> @@ -5261,6 +5261,7 @@ build_compound_literal (location_t loc, tree type, tree
> init, bool non_const)
> DECL_CONTEXT (decl) = current_function_decl;
> TREE_USED (decl) = 1;
> DECL_READ_P (decl) = 1;
> + DECL_ARTIFICIAL (decl) = 1;
> TREE_TYPE (decl) = type;
> TREE_READONLY (decl) = (TYPE_READONLY (type)
> || (TREE_CODE (type) == ARRAY_TYPE
> @@ -5297,7 +5298,6 @@ build_compound_literal (location_t loc, tree type, tree
> init, bool non_const)
> set_compound_literal_name (decl);
> DECL_DEFER_OUTPUT (decl) = 1;
> DECL_COMDAT (decl) = 1;
> - DECL_ARTIFICIAL (decl) = 1;
> DECL_IGNORED_P (decl) = 1;
> pushdecl (decl);
> rest_of_decl_compilation (decl, 1, 0);
> diff --git gcc/testsuite/gcc.dg/asan/pr80659.c
> gcc/testsuite/gcc.dg/asan/pr80659.c
> index e69de29..0cbf2e4 100644
> --- gcc/testsuite/gcc.dg/asan/pr80659.c
> +++ gcc/testsuite/gcc.dg/asan/pr80659.c
> @@ -0,0 +1,13 @@
> +/* PR sanitizer/80659 */
> +/* { dg-do compile } */
> +
> +void
> +foo (int a)
> +{
> + switch (a)
> + {
> + case 0:
> + (int[3]) { };
> + int h;
> + }
> +}
>
> Marek
>
>
--
Richard Biener <rguent...@suse.de>
SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB
21284 (AG Nuernberg)
