From f7741985be0234c3fe71e1f97740579e35726b92 Mon Sep 17 00:00:00 2001 From: Iago Toral Quiroga Date: Tue, 30 May 2017 13:25:35 +0200 Subject: [PATCH] glcpp: fix #undef to match latest spec update and GLSLang implementation MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit GLSL ES spec includes the following: "It is an error to undefine or to redefine a built-in (pre-defined) macro name." But desktop GLSL doesn't. This has sparked some discussion in Khronos, and the final conclusion was to update the GLSL 4.50 spec to include the following: "By convention, all macro names containing two consecutive underscores ( __ ) are reserved for use by underlying software layers. Defining or undefining such a name in a shader does not itself result in an error, but may result in unintended behaviors that stem from having multiple definitions of the same name. All macro names prefixed with “GL_” (“GL” followed by a single underscore) are also reserved, and defining or undefining such a name results in a compile-time error." In other words, undefining GL_* names should be an error, but undefining other names with a double underscore in them is not strictly prohibited in desktop GLSL. This patch fixes the preprocessor to apply these rules, following exactly the implementation already present in GLSLang. This fixes some tests in CTS. Khronos bug: https://cvs.khronos.org/bugzilla/show_bug.cgi?id=16003 Fixes: KHR-GL45.shaders.preprocessor.definitions.undefine_core_profile_vertex KHR-GL45.shaders.preprocessor.definitions.undefine_core_profile_fragment Reviewed-by: Samuel Pitoiset --- src/compiler/glsl/glcpp/glcpp-parse.y | 45 ++++++++++++++++++--------- 1 file changed, 31 insertions(+), 14 deletions(-) diff --git a/src/compiler/glsl/glcpp/glcpp-parse.y b/src/compiler/glsl/glcpp/glcpp-parse.y index fe211a0f0bd..f1719f90b11 100644 --- a/src/compiler/glsl/glcpp/glcpp-parse.y +++ b/src/compiler/glsl/glcpp/glcpp-parse.y @@ -287,24 +287,41 @@ control_line_success: * The GLSL ES 1.00 spec does not contain this text, but * dEQP's preprocess test in GLES2 checks for it. * - * Section 3.3 (Preprocessor) of the GLSL 1.30 spec says: + * Section 3.3 (Preprocessor) revision 7, of the GLSL 4.50 + * spec says: * - * #define and #undef functionality are defined as is - * standard for C++ preprocessors for macro definitions - * both with and without macro parameters. + * By convention, all macro names containing two consecutive + * underscores ( __ ) are reserved for use by underlying + * software layers. Defining or undefining such a name + * in a shader does not itself result in an error, but may + * result in unintended behaviors that stem from having + * multiple definitions of the same name. All macro names + * prefixed with "GL_" (...) are also reseved, and defining + * such a name results in a compile-time error. * - * At least as far as I can tell GCC allow '#undef __FILE__'. - * Furthermore, there are desktop OpenGL conformance tests - * that expect '#undef __VERSION__' and '#undef - * GL_core_profile' to work. + * The code below implements the same checks as GLSLang. */ - if (parser->is_gles && - (strcmp("__LINE__", $3) == 0 - || strcmp("__FILE__", $3) == 0 - || strcmp("__VERSION__", $3) == 0 - || strncmp("GL_", $3, 3) == 0)) + if (strncmp("GL_", $3, 3) == 0) glcpp_error(& @1, parser, "Built-in (pre-defined)" - " macro names cannot be undefined."); + " names beginning with GL_ cannot be undefined."); + else if (strstr($3, "__") != NULL) { + if (parser->is_gles + && parser->version >= 300 + && (strcmp("__LINE__", $3) == 0 + || strcmp("__FILE__", $3) == 0 + || strcmp("__VERSION__", $3) == 0)) { + glcpp_error(& @1, parser, "Built-in (pre-defined)" + " names cannot be undefined."); + } else if (parser->is_gles && parser->version <= 300) { + glcpp_error(& @1, parser, + " names containing consecutive underscores" + " are reserved."); + } else { + glcpp_warning(& @1, parser, + " names containing consecutive underscores" + " are reserved."); + } + } entry = _mesa_hash_table_search (parser->defines, $3); if (entry) { -- 2.30.2