From 901db25d5b7cd2ac2dd648b370c4bddf23dd5c44 Mon Sep 17 00:00:00 2001 From: Brian Paul Date: Tue, 8 May 2018 08:24:21 -0600 Subject: [PATCH] glsl: change ast_type_qualifier bitset size to work around GCC 5.4 bug Change the size of the bitset from 128 bits to 96. This works around an apparent GCC 5.4 bug in which bad SSE code is generated, leading to a crash in ast_type_qualifier::validate_in_qualifier() (ast_type.cpp:654). This can be repro'd with the Piglit test tests/spec/glsl-1.50/execution/ varying-struct-basic-gs-fs.shader_test Bugzilla:https://bugs.freedesktop.org/show_bug.cgi?id=105497 Cc: mesa-stable@lists.freedesktop.org Reviewed-by: Charmaine Lee Tested-by: Charmaine Lee Reviewed-by: Ian Romanick --- src/compiler/glsl/ast.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/src/compiler/glsl/ast.h b/src/compiler/glsl/ast.h index a1ec0d566f4..9b88ff51d48 100644 --- a/src/compiler/glsl/ast.h +++ b/src/compiler/glsl/ast.h @@ -474,7 +474,13 @@ enum { struct ast_type_qualifier { DECLARE_RALLOC_CXX_OPERATORS(ast_type_qualifier); - DECLARE_BITSET_T(bitset_t, 128); + /* Note: this bitset needs to have at least as many bits as the 'q' + * struct has flags, below. Previously, the size was 128 instead of 96. + * But an apparent bug in GCC 5.4.0 causes bad SSE code generation + * elsewhere, leading to a crash. 96 bits works around the issue. + * See https://bugs.freedesktop.org/show_bug.cgi?id=105497 + */ + DECLARE_BITSET_T(bitset_t, 96); union flags { struct { -- 2.30.2