On 05/08/2018 07:43 AM, Brian Paul wrote: > 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).
Is there a difference in the code quality on newer versions of GCC? This work-around seems fine, but I wonder if it should be restricted to the affected GCC versions. > 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-sta...@lists.freedesktop.org > --- > 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 a1ec0d5..9b88ff5 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 { _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
