[Mesa-dev] [PATCH] glsl: Guard against NULL dereference

[Matt Turner]

On Fri, May 20, 2016 at 8:58 AM, Mark Janes <mark.a.janes at intel.com> wrote:
> This trivially corrects mesa 3ca1c221, which introduced a check that
> crashes when a match is not found.
>
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=95005
> Fixes: piglit.spec.glsl-1_50.compiler.interface-blocks-name-reused-globally-4.vert
> ---
>  src/compiler/glsl/ast_to_hir.cpp | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/src/compiler/glsl/ast_to_hir.cpp b/src/compiler/glsl/ast_to_hir.cpp
> index ecfe684..a524fbd 100644
> --- a/src/compiler/glsl/ast_to_hir.cpp
> +++ b/src/compiler/glsl/ast_to_hir.cpp
> @@ -6920,7 +6920,7 @@ ast_struct_specifier::hir(exec_list *instructions,
>     if (!state->symbols->add_type(name, t)) {
>        const glsl_type *match = state->symbols->get_type(name);
>        /* allow struct matching for desktop GL - older UE4 does this */
> -      if (state->is_version(130, 0) && match->record_compare(t, false))
> +      if (match != NULL && state->is_version(130, 0) && match->record_compare(t, false))

For clarity I'd put the match != NULL check immediately before the '&&
match->...'