[Mesa-dev] [PATCH 1/2] glcpp: Check version_resolved in the proper place.

[Matt Turner]

On Sun, Jan 26, 2014 at 8:15 PM, Jordan Justen <jljusten at gmail.com> wrote:
> On Sun, Jan 26, 2014 at 6:14 PM, Matt Turner <mattst88 at gmail.com> wrote:
>> The check was in the wrong place, such that if a shader incorrectly put
>> a preprocessor token before the #version declaration, the version would
>> be resolved twice, leading to a segmentation fault when attempting to
>> redefine the __VERSION__ macro.
>>
>>  #define GL_ARB_sample_shading
>>  #version 130
>>  void main() {}
>>
>> Also, rename glcpp_parser_resolve_version to
>>              glcpp_parser_resolve_implicit_version to avoid confusion.
>> ---
>> I couldn't come up with something better to clarify the naming. Feel free
>> to suggest something better.
>>
>>  src/glsl/glcpp/glcpp-parse.y | 22 +++++++++++-----------
>>  src/glsl/glcpp/glcpp.h       |  2 +-
>>  src/glsl/glcpp/pp.c          |  2 +-
>>  3 files changed, 13 insertions(+), 13 deletions(-)
>>
>> diff --git a/src/glsl/glcpp/glcpp-parse.y b/src/glsl/glcpp/glcpp-parse.y
>> index 184e5c2..efcf139 100644
>> --- a/src/glsl/glcpp/glcpp-parse.y
>> +++ b/src/glsl/glcpp/glcpp-parse.y
>> @@ -194,7 +194,7 @@ line:
>>                 ralloc_asprintf_rewrite_tail (&parser->output, &parser->output_length, "\n");
>>         }
>>  |      HASH_LINE {
>> -               glcpp_parser_resolve_version(parser);
>> +               glcpp_parser_resolve_implicit_version(parser);
>>         } pp_tokens NEWLINE {
>>
>>                 if (parser->skip_stack == NULL ||
>> @@ -254,10 +254,10 @@ define:
>>
>>  control_line:
>>         HASH_DEFINE {
>> -               glcpp_parser_resolve_version(parser);
>> +               glcpp_parser_resolve_implicit_version(parser);
>>         } define
>>  |      HASH_UNDEF {
>> -               glcpp_parser_resolve_version(parser);
>> +               glcpp_parser_resolve_implicit_version(parser);
>>         } IDENTIFIER NEWLINE {
>>                 macro_t *macro = hash_table_find (parser->defines, $3);
>>                 if (macro) {
>> @@ -267,7 +267,7 @@ control_line:
>>                 ralloc_free ($3);
>>         }
>>  |      HASH_IF {
>> -               glcpp_parser_resolve_version(parser);
>> +               glcpp_parser_resolve_implicit_version(parser);
>>         } conditional_tokens NEWLINE {
>>                 /* Be careful to only evaluate the 'if' expression if
>>                  * we are not skipping. When we are skipping, we
>> @@ -299,14 +299,14 @@ control_line:
>>                 _glcpp_parser_skip_stack_push_if (parser, & @1, 0);
>>         }
>>  |      HASH_IFDEF {
>> -               glcpp_parser_resolve_version(parser);
>> +               glcpp_parser_resolve_implicit_version(parser);
>>         } IDENTIFIER junk NEWLINE {
>>                 macro_t *macro = hash_table_find (parser->defines, $3);
>>                 ralloc_free ($3);
>>                 _glcpp_parser_skip_stack_push_if (parser, & @1, macro != NULL);
>>         }
>>  |      HASH_IFNDEF {
>> -               glcpp_parser_resolve_version(parser);
>> +               glcpp_parser_resolve_implicit_version(parser);
>>         } IDENTIFIER junk NEWLINE {
>>                 macro_t *macro = hash_table_find (parser->defines, $3);
>>                 ralloc_free ($3);
>> @@ -380,7 +380,7 @@ control_line:
>>                 _glcpp_parser_handle_version_declaration(parser, $2, $3, true);
>>         }
>>  |      HASH NEWLINE {
>> -               glcpp_parser_resolve_version(parser);
>> +               glcpp_parser_resolve_implicit_version(parser);
>>         }
>>  ;
>>
>> @@ -2024,6 +2024,9 @@ _glcpp_parser_handle_version_declaration(glcpp_parser_t *parser, intmax_t versio
>>  {
>>         const struct gl_extensions *extensions = parser->extensions;
>>
>> +       if (parser->version_resolved)
>> +               return;
>> +
>>         parser->version_resolved = true;
>
> Would this lead to the version being stuck at the implicit version
> since parser->version_resolved would be set in the implicit case too?
>
> It looks like something like:
> #define GL_ARB_sample_shading
> #version 150
>
> ...might not end up hitting this code:
>   if (version >= 150)
>     add_builtin_define(parser, "GL_core_profile", 1);
>
> -Jordan

That's intended. #version has to be the first non-comment token. If
it's not, the version is 1.10 (or 1.00 in ES).