mesa: Add PrimitiveRestartFixedIndex to gl_constants
[mesa.git] / src / mesa / main / extensions.c
index 4ddf750dd6c3bcfec213e1b98ab6243fd0c2f8d0..6ded1bb426983fc1262405809f6f2c07d31d8ff1 100644 (file)
@@ -31,7 +31,7 @@
 
 
 #include "glheader.h"
-#include "imports.h"
+
 #include "context.h"
 #include "extensions.h"
 #include "macros.h"
 
 struct gl_extensions _mesa_extension_override_enables;
 struct gl_extensions _mesa_extension_override_disables;
-static char *extra_extensions = NULL;
-static char *cant_disable_extensions = NULL;
-
-enum {
-   DISABLE = 0,
-   GLL = 1 << API_OPENGL_COMPAT,       /* GL Legacy / Compatibility */
-   GLC = 1 << API_OPENGL_CORE,  /* GL Core */
-   GL  = (1 << API_OPENGL_COMPAT) | (1 << API_OPENGL_CORE),
-   ES1 = 1 << API_OPENGLES,
-   ES2 = 1 << API_OPENGLES2,
-   ES3 = 1 << (API_OPENGL_LAST + 1),
-   ES31 = 1 << (API_OPENGL_LAST + 2),
-};
-
-/**
- * \brief An element of the \c extension_table.
- */
-struct extension {
-   /** Name of extension, such as "GL_ARB_depth_clamp". */
-   const char *name;
-
-   /** Offset (in bytes) of the corresponding member in struct gl_extensions. */
-   size_t offset;
-
-   /** Set of API's in which the extension exists, as a bitset. */
-   uint8_t api_set;
-
-   /** Year the extension was proposed or approved.  Used to sort the 
-    * extension string chronologically. */
-   uint16_t year;
-};
 
+#define MAX_UNRECOGNIZED_EXTENSIONS 16
+static struct {
+   char *env;
+   const char *names[MAX_UNRECOGNIZED_EXTENSIONS];
+} unrecognized_extensions;
 
 /**
  * Given a member \c x of struct gl_extensions, return offset of
@@ -78,372 +52,46 @@ struct extension {
  */
 #define o(x) offsetof(struct gl_extensions, x)
 
-
-/**
- * \brief Table of supported OpenGL extensions for all API's.
- */
-static const struct extension extension_table[] = {
-#define EXT(name_str, driver_cap, api_flags, yyyy) \
-        { .name = "GL_" #name_str, .offset = o(driver_cap), .api_set = api_flags, .year = yyyy},
-   EXT(ARB_ES2_compatibility                   , ARB_ES2_compatibility                  , GL                   , 2009)
-   EXT(ARB_ES3_compatibility                   , ARB_ES3_compatibility                  , GL                   , 2012)
-   EXT(ARB_arrays_of_arrays                    , ARB_arrays_of_arrays                   , GL                   , 2012)
-   EXT(ARB_base_instance                       , ARB_base_instance                      , GL                   , 2011)
-   EXT(ARB_blend_func_extended                 , ARB_blend_func_extended                , GL                   , 2009)
-   EXT(ARB_buffer_storage                      , ARB_buffer_storage                     , GL                   , 2013)
-   EXT(ARB_clear_buffer_object                 , dummy_true                             , GL                   , 2012)
-   EXT(ARB_clear_texture                       , ARB_clear_texture                      , GL                   , 2013)
-   EXT(ARB_clip_control                        , ARB_clip_control                       , GL                   , 2014)
-   EXT(ARB_color_buffer_float                  , ARB_color_buffer_float                 , GL                   , 2004)
-   EXT(ARB_compressed_texture_pixel_storage    , dummy_true                             , GL                   , 2011)
-   EXT(ARB_compute_shader                      , ARB_compute_shader                     , GL                   , 2012)
-   EXT(ARB_conditional_render_inverted         , ARB_conditional_render_inverted        , GL                   , 2014)
-   EXT(ARB_copy_buffer                         , dummy_true                             , GL                   , 2008)
-   EXT(ARB_copy_image                          , ARB_copy_image                         , GL                   , 2012)
-   EXT(ARB_conservative_depth                  , ARB_conservative_depth                 , GL                   , 2011)
-   EXT(ARB_debug_output                        , dummy_true                             , GL                   , 2009)
-   EXT(ARB_depth_buffer_float                  , ARB_depth_buffer_float                 , GL                   , 2008)
-   EXT(ARB_depth_clamp                         , ARB_depth_clamp                        , GL                   , 2003)
-   EXT(ARB_depth_texture                       , ARB_depth_texture                      , GLL                  , 2001)
-   EXT(ARB_derivative_control                  , ARB_derivative_control                 , GL                   , 2014)
-   EXT(ARB_direct_state_access                 , dummy_true                             , GLC                  , 2014)
-   EXT(ARB_draw_buffers                        , dummy_true                             , GL                   , 2002)
-   EXT(ARB_draw_buffers_blend                  , ARB_draw_buffers_blend                 , GL                   , 2009)
-   EXT(ARB_draw_elements_base_vertex           , ARB_draw_elements_base_vertex          , GL                   , 2009)
-   EXT(ARB_draw_indirect                       , ARB_draw_indirect                      , GLC                  , 2010)
-   EXT(ARB_draw_instanced                      , ARB_draw_instanced                     , GL                   , 2008)
-   EXT(ARB_enhanced_layouts                    , ARB_enhanced_layouts                   , GLC                  , 2013)
-   EXT(ARB_explicit_attrib_location            , ARB_explicit_attrib_location           , GL                   , 2009)
-   EXT(ARB_explicit_uniform_location           , ARB_explicit_uniform_location          , GL                   , 2012)
-   EXT(ARB_fragment_coord_conventions          , ARB_fragment_coord_conventions         , GL                   , 2009)
-   EXT(ARB_fragment_layer_viewport             , ARB_fragment_layer_viewport            , GLC                  , 2012)
-   EXT(ARB_fragment_program                    , ARB_fragment_program                   , GLL                  , 2002)
-   EXT(ARB_fragment_program_shadow             , ARB_fragment_program_shadow            , GLL                  , 2003)
-   EXT(ARB_fragment_shader                     , ARB_fragment_shader                    , GL                   , 2002)
-   EXT(ARB_framebuffer_no_attachments          , ARB_framebuffer_no_attachments         , GL                   , 2012)
-   EXT(ARB_framebuffer_object                  , ARB_framebuffer_object                 , GL                   , 2005)
-   EXT(ARB_framebuffer_sRGB                    , EXT_framebuffer_sRGB                   , GL                   , 1998)
-   EXT(ARB_get_program_binary                  , dummy_true                             , GL                   , 2010)
-   EXT(ARB_get_texture_sub_image               , dummy_true                             , GL                   , 2014)
-   EXT(ARB_gpu_shader5                         , ARB_gpu_shader5                        , GLC                  , 2010)
-   EXT(ARB_gpu_shader_fp64                     , ARB_gpu_shader_fp64                    , GLC                  , 2010)
-   EXT(ARB_half_float_pixel                    , dummy_true                             , GL                   , 2003)
-   EXT(ARB_half_float_vertex                   , ARB_half_float_vertex                  , GL                   , 2008)
-   EXT(ARB_instanced_arrays                    , ARB_instanced_arrays                   , GL                   , 2008)
-   EXT(ARB_internalformat_query                , ARB_internalformat_query               , GL                   , 2011)
-   EXT(ARB_invalidate_subdata                  , dummy_true                             , GL                   , 2012)
-   EXT(ARB_map_buffer_alignment                , dummy_true                             , GL                   , 2011)
-   EXT(ARB_map_buffer_range                    , ARB_map_buffer_range                   , GL                   , 2008)
-   EXT(ARB_multi_bind                          , dummy_true                             , GL                   , 2013)
-   EXT(ARB_multi_draw_indirect                 , ARB_draw_indirect                      , GLC                  , 2012)
-   EXT(ARB_multisample                         , dummy_true                             , GLL                  , 1994)
-   EXT(ARB_multitexture                        , dummy_true                             , GLL                  , 1998)
-   EXT(ARB_occlusion_query2                    , ARB_occlusion_query2                   , GL                   , 2003)
-   EXT(ARB_occlusion_query                     , ARB_occlusion_query                    , GLL                  , 2001)
-   EXT(ARB_pipeline_statistics_query           , ARB_pipeline_statistics_query          , GL                   , 2014)
-   EXT(ARB_pixel_buffer_object                 , EXT_pixel_buffer_object                , GL                   , 2004)
-   EXT(ARB_point_parameters                    , EXT_point_parameters                   , GLL                  , 1997)
-   EXT(ARB_point_sprite                        , ARB_point_sprite                       , GL                   , 2003)
-   EXT(ARB_program_interface_query             , dummy_true                             , GL                   , 2012)
-   EXT(ARB_provoking_vertex                    , EXT_provoking_vertex                   , GL                   , 2009)
-   EXT(ARB_robustness                          , dummy_true                             , GL                   , 2010)
-   EXT(ARB_sample_shading                      , ARB_sample_shading                     , GL                   , 2009)
-   EXT(ARB_sampler_objects                     , dummy_true                             , GL                   , 2009)
-   EXT(ARB_seamless_cube_map                   , ARB_seamless_cube_map                  , GL                   , 2009)
-   EXT(ARB_seamless_cubemap_per_texture        , AMD_seamless_cubemap_per_texture       , GL                   , 2013)
-   EXT(ARB_separate_shader_objects             , dummy_true                             , GL                   , 2010)
-   EXT(ARB_shader_atomic_counters              , ARB_shader_atomic_counters             , GL                   , 2011)
-   EXT(ARB_shader_bit_encoding                 , ARB_shader_bit_encoding                , GL                   , 2010)
-   EXT(ARB_shader_clock                        , ARB_shader_clock                       , GL                   , 2015)
-   EXT(ARB_shader_image_load_store             , ARB_shader_image_load_store            , GL                   , 2011)
-   EXT(ARB_shader_image_size                   , ARB_shader_image_size                  , GL                   , 2012)
-   EXT(ARB_shader_objects                      , dummy_true                             , GL                   , 2002)
-   EXT(ARB_shader_precision                    , ARB_shader_precision                   , GL                   , 2010)
-   EXT(ARB_shader_stencil_export               , ARB_shader_stencil_export              , GL                   , 2009)
-   EXT(ARB_shader_storage_buffer_object        , ARB_shader_storage_buffer_object       , GL                   , 2012)
-   EXT(ARB_shader_subroutine                   , ARB_shader_subroutine                  , GLC                  , 2010)
-   EXT(ARB_shader_texture_image_samples        , ARB_shader_texture_image_samples       , GL                   , 2014)
-   EXT(ARB_shader_texture_lod                  , ARB_shader_texture_lod                 , GL                   , 2009)
-   EXT(ARB_shading_language_100                , dummy_true                             , GLL                  , 2003)
-   EXT(ARB_shading_language_packing            , ARB_shading_language_packing           , GL                   , 2011)
-   EXT(ARB_shading_language_420pack            , ARB_shading_language_420pack           , GL                   , 2011)
-   EXT(ARB_shadow                              , ARB_shadow                             , GLL                  , 2001)
-   EXT(ARB_stencil_texturing                   , ARB_stencil_texturing                  , GL                   , 2012)
-   EXT(ARB_sync                                , ARB_sync                               , GL                   , 2003)
-   EXT(ARB_texture_barrier                     , NV_texture_barrier                     , GL                   , 2014)
-   EXT(ARB_tessellation_shader                 , ARB_tessellation_shader                , GLC                  , 2009)
-   EXT(ARB_texture_border_clamp                , ARB_texture_border_clamp               , GLL                  , 2000)
-   EXT(ARB_texture_buffer_object               , ARB_texture_buffer_object              , GLC                  , 2008)
-   EXT(ARB_texture_buffer_object_rgb32         , ARB_texture_buffer_object_rgb32        , GLC                  , 2009)
-   EXT(ARB_texture_buffer_range                , ARB_texture_buffer_range               , GLC                  , 2012)
-   EXT(ARB_texture_compression                 , dummy_true                             , GLL                  , 2000)
-   EXT(ARB_texture_compression_bptc            , ARB_texture_compression_bptc           , GL                   , 2010)
-   EXT(ARB_texture_compression_rgtc            , ARB_texture_compression_rgtc           , GL                   , 2004)
-   EXT(ARB_texture_cube_map                    , ARB_texture_cube_map                   , GLL                  , 1999)
-   EXT(ARB_texture_cube_map_array              , ARB_texture_cube_map_array             , GL                   , 2009)
-   EXT(ARB_texture_env_add                     , dummy_true                             , GLL                  , 1999)
-   EXT(ARB_texture_env_combine                 , ARB_texture_env_combine                , GLL                  , 2001)
-   EXT(ARB_texture_env_crossbar                , ARB_texture_env_crossbar               , GLL                  , 2001)
-   EXT(ARB_texture_env_dot3                    , ARB_texture_env_dot3                   , GLL                  , 2001)
-   EXT(ARB_texture_float                       , ARB_texture_float                      , GL                   , 2004)
-   EXT(ARB_texture_gather                      , ARB_texture_gather                     , GL                   , 2009)
-   EXT(ARB_texture_mirrored_repeat             , dummy_true                             , GLL                  , 2001)
-   EXT(ARB_texture_mirror_clamp_to_edge        , ARB_texture_mirror_clamp_to_edge       , GL                   , 2013)
-   EXT(ARB_texture_multisample                 , ARB_texture_multisample                , GL                   , 2009)
-   EXT(ARB_texture_non_power_of_two            , ARB_texture_non_power_of_two           , GL                   , 2003)
-   EXT(ARB_texture_query_levels                , ARB_texture_query_levels               , GL                   , 2012)
-   EXT(ARB_texture_query_lod                   , ARB_texture_query_lod                  , GL                   , 2009)
-   EXT(ARB_texture_rectangle                   , NV_texture_rectangle                   , GL                   , 2004)
-   EXT(ARB_texture_rgb10_a2ui                  , ARB_texture_rgb10_a2ui                 , GL                   , 2009)
-   EXT(ARB_texture_rg                          , ARB_texture_rg                         , GL                   , 2008)
-   EXT(ARB_texture_stencil8                    , ARB_texture_stencil8                   , GL                   , 2013)
-   EXT(ARB_texture_storage                     , dummy_true                             , GL                   , 2011)
-   EXT(ARB_texture_storage_multisample         , ARB_texture_multisample                , GL                   , 2012)
-   EXT(ARB_texture_view                        , ARB_texture_view                       , GL                   , 2012)
-   EXT(ARB_texture_swizzle                     , EXT_texture_swizzle                    , GL                   , 2008)
-   EXT(ARB_timer_query                         , ARB_timer_query                        , GL                   , 2010)
-   EXT(ARB_transform_feedback2                 , ARB_transform_feedback2                , GL                   , 2010)
-   EXT(ARB_transform_feedback3                 , ARB_transform_feedback3                , GL                   , 2010)
-   EXT(ARB_transform_feedback_instanced        , ARB_transform_feedback_instanced       , GL                   , 2011)
-   EXT(ARB_transpose_matrix                    , dummy_true                             , GLL                  , 1999)
-   EXT(ARB_uniform_buffer_object               , ARB_uniform_buffer_object              , GL                   , 2009)
-   EXT(ARB_vertex_array_bgra                   , EXT_vertex_array_bgra                  , GL                   , 2008)
-   EXT(ARB_vertex_array_object                 , dummy_true                             , GL                   , 2006)
-   EXT(ARB_vertex_attrib_binding               , dummy_true                             , GL                   , 2012)
-   EXT(ARB_vertex_buffer_object                , dummy_true                             , GLL                  , 2003)
-   EXT(ARB_vertex_program                      , ARB_vertex_program                     , GLL                  , 2002)
-   EXT(ARB_vertex_shader                       , ARB_vertex_shader                      , GL                   , 2002)
-   EXT(ARB_vertex_attrib_64bit                 , ARB_vertex_attrib_64bit                , GLC                  , 2010)
-   EXT(ARB_vertex_type_10f_11f_11f_rev         , ARB_vertex_type_10f_11f_11f_rev        , GL                   , 2013)
-   EXT(ARB_vertex_type_2_10_10_10_rev          , ARB_vertex_type_2_10_10_10_rev         , GL                   , 2009)
-   EXT(ARB_viewport_array                      , ARB_viewport_array                     , GLC                  , 2010)
-   EXT(ARB_window_pos                          , dummy_true                             , GLL                  , 2001)
-
-   EXT(EXT_abgr                                , dummy_true                             , GL                   , 1995)
-   EXT(EXT_bgra                                , dummy_true                             , GLL                  , 1995)
-   EXT(EXT_blend_color                         , EXT_blend_color                        , GLL                  , 1995)
-   EXT(EXT_blend_equation_separate             , EXT_blend_equation_separate            , GL                   , 2003)
-   EXT(EXT_blend_func_separate                 , EXT_blend_func_separate                , GLL                  , 1999)
-   EXT(EXT_buffer_storage                      , ARB_buffer_storage                     , ES31                 , 2015)
-   EXT(EXT_discard_framebuffer                 , dummy_true                             ,       ES1 | ES2      , 2009)
-   EXT(EXT_blend_minmax                        , EXT_blend_minmax                       , GLL | ES1 | ES2      , 1995)
-   EXT(EXT_blend_subtract                      , dummy_true                             , GLL                  , 1995)
-   EXT(EXT_compiled_vertex_array               , dummy_true                             , GLL                  , 1996)
-   EXT(EXT_copy_texture                        , dummy_true                             , GLL                  , 1995)
-   EXT(EXT_depth_bounds_test                   , EXT_depth_bounds_test                  , GL                   , 2002)
-   EXT(EXT_draw_buffers                        , dummy_true                             ,             ES2      , 2012)
-   EXT(EXT_draw_buffers2                       , EXT_draw_buffers2                      , GL                   , 2006)
-   EXT(EXT_draw_elements_base_vertex           , ARB_draw_elements_base_vertex          , ES2                  , 2014)
-   EXT(EXT_draw_instanced                      , ARB_draw_instanced                     , GL                   , 2006)
-   EXT(EXT_draw_range_elements                 , dummy_true                             , GLL                  , 1997)
-   EXT(EXT_fog_coord                           , dummy_true                             , GLL                  , 1999)
-   EXT(EXT_framebuffer_blit                    , dummy_true                             , GL                   , 2005)
-   EXT(EXT_framebuffer_multisample             , EXT_framebuffer_multisample            , GL                   , 2005)
-   EXT(EXT_framebuffer_multisample_blit_scaled , EXT_framebuffer_multisample_blit_scaled, GL                   , 2011)
-   EXT(EXT_framebuffer_object                  , dummy_true                             , GLL                  , 2000)
-   EXT(EXT_framebuffer_sRGB                    , EXT_framebuffer_sRGB                   , GL                   , 1998)
-   EXT(EXT_gpu_program_parameters              , EXT_gpu_program_parameters             , GLL                  , 2006)
-   EXT(EXT_gpu_shader4                         , EXT_gpu_shader4                        , GL                   , 2006)
-   EXT(EXT_map_buffer_range                    , ARB_map_buffer_range                   ,       ES1 | ES2      , 2012)
-   EXT(EXT_multi_draw_arrays                   , dummy_true                             , GLL | ES1 | ES2      , 1999)
-   EXT(EXT_packed_depth_stencil                , dummy_true                             , GL                   , 2005)
-   EXT(EXT_packed_float                        , EXT_packed_float                       , GL                   , 2004)
-   EXT(EXT_packed_pixels                       , dummy_true                             , GLL                  , 1997)
-   EXT(EXT_pixel_buffer_object                 , EXT_pixel_buffer_object                , GL                   , 2004)
-   EXT(EXT_point_parameters                    , EXT_point_parameters                   , GLL                  , 1997)
-   EXT(EXT_polygon_offset                      , dummy_true                             , GLL                  , 1995)
-   EXT(EXT_polygon_offset_clamp                , EXT_polygon_offset_clamp               , GL                   , 2014)
-   EXT(EXT_provoking_vertex                    , EXT_provoking_vertex                   , GL                   , 2009)
-   EXT(EXT_rescale_normal                      , dummy_true                             , GLL                  , 1997)
-   EXT(EXT_secondary_color                     , dummy_true                             , GLL                  , 1999)
-   EXT(EXT_separate_shader_objects             , dummy_true                             ,            ES2       , 2013)
-   EXT(EXT_separate_specular_color             , dummy_true                             , GLL                  , 1997)
-   EXT(EXT_shader_integer_mix                  , EXT_shader_integer_mix                 , GL       | ES3       , 2013)
-   EXT(EXT_shadow_funcs                        , ARB_shadow                             , GLL                  , 2002)
-   EXT(EXT_stencil_two_side                    , EXT_stencil_two_side                   , GLL                  , 2001)
-   EXT(EXT_stencil_wrap                        , dummy_true                             , GLL                  , 2002)
-   EXT(EXT_subtexture                          , dummy_true                             , GLL                  , 1995)
-   EXT(EXT_texture3D                           , EXT_texture3D                          , GLL                  , 1996)
-   EXT(EXT_texture_array                       , EXT_texture_array                      , GL                   , 2006)
-   EXT(EXT_texture_compression_dxt1            , ANGLE_texture_compression_dxt          , GL | ES1 | ES2       , 2004)
-   EXT(ANGLE_texture_compression_dxt3          , ANGLE_texture_compression_dxt          , GL | ES1 | ES2       , 2011)
-   EXT(ANGLE_texture_compression_dxt5          , ANGLE_texture_compression_dxt          , GL | ES1 | ES2       , 2011)
-   EXT(EXT_texture_compression_latc            , EXT_texture_compression_latc           , GLL                  , 2006)
-   EXT(EXT_texture_compression_rgtc            , ARB_texture_compression_rgtc           , GL                   , 2004)
-   EXT(EXT_texture_compression_s3tc            , EXT_texture_compression_s3tc           , GL                   , 2000)
-   EXT(EXT_texture_cube_map                    , ARB_texture_cube_map                   , GLL                  , 2001)
-   EXT(EXT_texture_edge_clamp                  , dummy_true                             , GLL                  , 1997)
-   EXT(EXT_texture_env_add                     , dummy_true                             , GLL                  , 1999)
-   EXT(EXT_texture_env_combine                 , dummy_true                             , GLL                  , 2000)
-   EXT(EXT_texture_env_dot3                    , EXT_texture_env_dot3                   , GLL                  , 2000)
-   EXT(EXT_texture_filter_anisotropic          , EXT_texture_filter_anisotropic         , GL | ES1 | ES2       , 1999)
-   EXT(EXT_texture_format_BGRA8888             , dummy_true                             ,      ES1 | ES2       , 2005)
-   EXT(EXT_texture_rg                          , ARB_texture_rg                         ,            ES2       , 2011)
-   EXT(EXT_read_format_bgra                    , dummy_true                             ,      ES1 | ES2       , 2009)
-   EXT(EXT_texture_integer                     , EXT_texture_integer                    , GL                   , 2006)
-   EXT(EXT_texture_lod_bias                    , dummy_true                             , GLL | ES1            , 1999)
-   EXT(EXT_texture_mirror_clamp                , EXT_texture_mirror_clamp               , GL                   , 2004)
-   EXT(EXT_texture_object                      , dummy_true                             , GLL                  , 1995)
-   EXT(EXT_texture                             , dummy_true                             , GLL                  , 1996)
-   EXT(EXT_texture_rectangle                   , NV_texture_rectangle                   , GLL                  , 2004)
-   EXT(EXT_texture_shared_exponent             , EXT_texture_shared_exponent            , GL                   , 2004)
-   EXT(EXT_texture_snorm                       , EXT_texture_snorm                      , GL                   , 2009)
-   EXT(EXT_texture_sRGB                        , EXT_texture_sRGB                       , GL                   , 2004)
-   EXT(EXT_texture_sRGB_decode                 , EXT_texture_sRGB_decode                , GL                   , 2006)
-   EXT(EXT_texture_swizzle                     , EXT_texture_swizzle                    , GL                   , 2008)
-   EXT(EXT_texture_type_2_10_10_10_REV         , dummy_true                             ,            ES2       , 2008)
-   EXT(EXT_timer_query                         , EXT_timer_query                        , GL                   , 2006)
-   EXT(EXT_transform_feedback                  , EXT_transform_feedback                 , GL                   , 2011)
-   EXT(EXT_unpack_subimage                     , dummy_true                             ,            ES2       , 2011)
-   EXT(EXT_vertex_array_bgra                   , EXT_vertex_array_bgra                  , GL                   , 2008)
-   EXT(EXT_vertex_array                        , dummy_true                             , GLL                  , 1995)
-   EXT(EXT_color_buffer_float                  , dummy_true                             ,                  ES3 , 2013)
-
-
-   EXT(OES_blend_equation_separate             , EXT_blend_equation_separate            ,      ES1             , 2009)
-   EXT(OES_blend_func_separate                 , EXT_blend_func_separate                ,      ES1             , 2009)
-   EXT(OES_blend_subtract                      , dummy_true                             ,      ES1             , 2009)
-   EXT(OES_byte_coordinates                    , dummy_true                             ,      ES1             , 2002)
-   EXT(OES_compressed_ETC1_RGB8_texture        , OES_compressed_ETC1_RGB8_texture       ,      ES1 | ES2       , 2005)
-   EXT(OES_compressed_paletted_texture         , dummy_true                             ,      ES1             , 2003)
-   EXT(OES_depth24                             , dummy_true                             ,      ES1 | ES2       , 2005)
-   EXT(OES_depth32                             , dummy_false                            ,       DISABLE        , 2005)
-   EXT(OES_depth_texture                       , ARB_depth_texture                      ,            ES2       , 2006)
-   EXT(OES_depth_texture_cube_map              , OES_depth_texture_cube_map             ,            ES2       , 2012)
-   EXT(OES_draw_elements_base_vertex           , ARB_draw_elements_base_vertex          , ES2                  , 2014)
-   EXT(OES_draw_texture                        , OES_draw_texture                       ,      ES1             , 2004)
-   EXT(OES_EGL_sync                            , dummy_true                             ,      ES1 | ES2       , 2010)
-   EXT(OES_EGL_image                           , OES_EGL_image                          , GL | ES1 | ES2       , 2006) /* FIXME: Mesa expects GL_OES_EGL_image to be available in OpenGL contexts. */
-   EXT(OES_EGL_image_external                  , OES_EGL_image_external                 ,      ES1 | ES2       , 2010)
-   EXT(OES_element_index_uint                  , dummy_true                             ,      ES1 | ES2       , 2005)
-   EXT(OES_fbo_render_mipmap                   , dummy_true                             ,      ES1 | ES2       , 2005)
-   EXT(OES_fixed_point                         , dummy_true                             ,      ES1             , 2002)
-   EXT(OES_framebuffer_object                  , dummy_true                             ,      ES1             , 2005)
-   EXT(OES_get_program_binary                  , dummy_true                             ,            ES2       , 2008)
-   EXT(OES_mapbuffer                           , dummy_true                             ,      ES1 | ES2       , 2005)
-   EXT(OES_packed_depth_stencil                , dummy_true                             ,      ES1 | ES2       , 2007)
-   EXT(OES_point_size_array                    , dummy_true                             ,      ES1             , 2004)
-   EXT(OES_point_sprite                        , ARB_point_sprite                       ,      ES1             , 2004)
-   EXT(OES_query_matrix                        , dummy_true                             ,      ES1             , 2003)
-   EXT(OES_read_format                         , dummy_true                             , GL | ES1             , 2003)
-   EXT(OES_rgb8_rgba8                          , dummy_true                             ,      ES1 | ES2       , 2005)
-   EXT(OES_single_precision                    , dummy_true                             ,      ES1             , 2003)
-   EXT(OES_standard_derivatives                , OES_standard_derivatives               ,            ES2       , 2005)
-   EXT(OES_stencil1                            , dummy_false                            ,       DISABLE        , 2005)
-   EXT(OES_stencil4                            , dummy_false                            ,       DISABLE        , 2005)
-   EXT(OES_stencil8                            , dummy_true                             ,      ES1 | ES2       , 2005)
-   EXT(OES_stencil_wrap                        , dummy_true                             ,      ES1             , 2002)
-   EXT(OES_surfaceless_context                 , dummy_true                             ,      ES1 | ES2       , 2012)
-   EXT(OES_texture_3D                          , EXT_texture3D                          ,            ES2       , 2005)
-   EXT(OES_texture_cube_map                    , ARB_texture_cube_map                   ,      ES1             , 2007)
-   EXT(OES_texture_env_crossbar                , ARB_texture_env_crossbar               ,      ES1             , 2005)
-   EXT(OES_texture_float                       , OES_texture_float                      ,            ES2       , 2005)
-   EXT(OES_texture_float_linear                , OES_texture_float_linear               ,            ES2       , 2005)
-   EXT(OES_texture_half_float                  , OES_texture_half_float                 ,            ES2       , 2005)
-   EXT(OES_texture_half_float_linear           , OES_texture_half_float_linear          ,            ES2       , 2005)
-   EXT(OES_texture_mirrored_repeat             , dummy_true                             ,      ES1             , 2005)
-   EXT(OES_texture_storage_multisample_2d_array, ARB_texture_multisample                ,           ES31       , 2014)
-   EXT(OES_texture_npot                        , ARB_texture_non_power_of_two           ,      ES1 | ES2       , 2005)
-   EXT(OES_vertex_array_object                 , dummy_true                             ,      ES1 | ES2       , 2010)
-
-
-   EXT(KHR_debug                               , dummy_true                             , GL                   , 2012)
-   EXT(KHR_context_flush_control               , dummy_true                             , GL       | ES2       , 2014)
-   EXT(KHR_texture_compression_astc_hdr        , KHR_texture_compression_astc_hdr       , GL       | ES2       , 2012)
-   EXT(KHR_texture_compression_astc_ldr        , KHR_texture_compression_astc_ldr       , GL       | ES2       , 2012)
-
-
-   EXT(3DFX_texture_compression_FXT1           , TDFX_texture_compression_FXT1          , GL                   , 1999)
-   EXT(AMD_conservative_depth                  , ARB_conservative_depth                 , GL                   , 2009)
-   EXT(AMD_draw_buffers_blend                  , ARB_draw_buffers_blend                 , GL                   , 2009)
-   EXT(AMD_performance_monitor                 , AMD_performance_monitor                , GL                   , 2007)
-   EXT(AMD_pinned_memory                       , AMD_pinned_memory                      , GL                   , 2013)
-   EXT(AMD_seamless_cubemap_per_texture        , AMD_seamless_cubemap_per_texture       , GL                   , 2009)
-   EXT(AMD_shader_stencil_export               , ARB_shader_stencil_export              , GL                   , 2009)
-   EXT(AMD_shader_trinary_minmax               , dummy_true                             , GL                   , 2012)
-   EXT(AMD_vertex_shader_layer                 , AMD_vertex_shader_layer                , GLC                  , 2012)
-   EXT(AMD_vertex_shader_viewport_index        , AMD_vertex_shader_viewport_index       , GLC                  , 2012)
-   EXT(APPLE_object_purgeable                  , APPLE_object_purgeable                 , GL                   , 2006)
-   EXT(APPLE_packed_pixels                     , dummy_true                             , GLL                  , 2002)
-   EXT(APPLE_texture_max_level                 , dummy_true                             ,      ES1 | ES2       , 2009)
-   EXT(APPLE_vertex_array_object               , dummy_true                             , GLL                  , 2002)
-   EXT(ATI_blend_equation_separate             , EXT_blend_equation_separate            , GL                   , 2003)
-   EXT(ATI_draw_buffers                        , dummy_true                             , GLL                  , 2002)
-   EXT(ATI_fragment_shader                     , ATI_fragment_shader                    , GLL                  , 2001)
-   EXT(ATI_separate_stencil                    , ATI_separate_stencil                   , GLL                  , 2006)
-   EXT(ATI_texture_compression_3dc             , ATI_texture_compression_3dc            , GLL                  , 2004)
-   EXT(ATI_texture_env_combine3                , ATI_texture_env_combine3               , GLL                  , 2002)
-   EXT(ATI_texture_float                       , ARB_texture_float                      , GL                   , 2002)
-   EXT(ATI_texture_mirror_once                 , ATI_texture_mirror_once                , GL                   , 2006)
-   EXT(IBM_multimode_draw_arrays               , dummy_true                             , GL                   , 1998)
-   EXT(IBM_rasterpos_clip                      , dummy_true                             , GLL                  , 1996)
-   EXT(IBM_texture_mirrored_repeat             , dummy_true                             , GLL                  , 1998)
-   EXT(INGR_blend_func_separate                , EXT_blend_func_separate                , GLL                  , 1999)
-   EXT(INTEL_performance_query                 , INTEL_performance_query                , GL       | ES2       , 2013)
-   EXT(MESA_pack_invert                        , MESA_pack_invert                       , GL                   , 2002)
-   EXT(MESA_texture_signed_rgba                , EXT_texture_snorm                      , GL                   , 2009)
-   EXT(MESA_window_pos                         , dummy_true                             , GLL                  , 2000)
-   EXT(MESA_ycbcr_texture                      , MESA_ycbcr_texture                     , GL                   , 2002)
-   EXT(NV_blend_square                         , dummy_true                             , GLL                  , 1999)
-   EXT(NV_conditional_render                   , NV_conditional_render                  , GL                   , 2008)
-   EXT(NV_depth_clamp                          , ARB_depth_clamp                        , GL                   , 2001)
-   EXT(NV_draw_buffers                         , dummy_true                             ,            ES2       , 2011)
-   EXT(NV_fbo_color_attachments                , dummy_true                             ,            ES2       , 2010)
-   EXT(NV_fog_distance                         , NV_fog_distance                        , GLL                  , 2001)
-   EXT(NV_fragment_program_option              , NV_fragment_program_option             , GLL                  , 2005)
-   EXT(NV_light_max_exponent                   , dummy_true                             , GLL                  , 1999)
-   EXT(NV_packed_depth_stencil                 , dummy_true                             , GL                   , 2000)
-   EXT(NV_point_sprite                         , NV_point_sprite                        , GL                   , 2001)
-   EXT(NV_primitive_restart                    , NV_primitive_restart                   , GLL                  , 2002)
-   EXT(NV_read_buffer                          , dummy_true                             ,            ES2       , 2011)
-   EXT(NV_read_depth                           , dummy_true                             ,            ES2       , 2011)
-   EXT(NV_read_depth_stencil                   , dummy_true                             ,            ES2       , 2011)
-   EXT(NV_read_stencil                         , dummy_true                             ,            ES2       , 2011)
-   EXT(NV_texgen_reflection                    , dummy_true                             , GLL                  , 1999)
-   EXT(NV_texture_barrier                      , NV_texture_barrier                     , GL                   , 2009)
-   EXT(NV_texture_env_combine4                 , NV_texture_env_combine4                , GLL                  , 1999)
-   EXT(NV_texture_rectangle                    , NV_texture_rectangle                   , GLL                  , 2000)
-   EXT(NV_vdpau_interop                        , NV_vdpau_interop                       , GL                   , 2010)
-   EXT(S3_s3tc                                 , ANGLE_texture_compression_dxt          , GL                   , 1999)
-   EXT(SGIS_generate_mipmap                    , dummy_true                             , GLL                  , 1997)
-   EXT(SGIS_texture_border_clamp               , ARB_texture_border_clamp               , GLL                  , 1997)
-   EXT(SGIS_texture_edge_clamp                 , dummy_true                             , GLL                  , 1997)
-   EXT(SGIS_texture_lod                        , dummy_true                             , GLL                  , 1997)
-   EXT(SUN_multi_draw_arrays                   , dummy_true                             , GLL                  , 1999)
-#undef EXT
-};
-
+static int
+extension_name_compare(const void *name, const void *elem)
+{
+   const struct mesa_extension *entry = elem;
+   return strcmp(name, entry->name);
+}
 
 /**
  * Given an extension name, lookup up the corresponding member of struct
- * gl_extensions and return that member's offset (in bytes).  If the name is
- * not found in the \c extension_table, return 0.
+ * gl_extensions and return that member's index.  If the name is
+ * not found in the \c _mesa_extension_table, return -1.
  *
  * \param name Name of extension.
- * \return Offset of member in struct gl_extensions.
+ * \return Index of member in struct gl_extensions.
  */
-static size_t
-name_to_offset(const char* name)
+static int
+name_to_index(const char* name)
 {
-   unsigned i;
+   const struct mesa_extension *entry;
 
-   if (name == 0)
-      return 0;
+   if (!name)
+      return -1;
 
-   for (i = 0; i < ARRAY_SIZE(extension_table); ++i) {
-      if (strcmp(name, extension_table[i].name) == 0)
-        return extension_table[i].offset;
-   }
+   entry = bsearch(name,
+                   _mesa_extension_table, MESA_EXTENSION_COUNT,
+                   sizeof(_mesa_extension_table[0]),
+                   extension_name_compare);
+
+   if (entry)
+      return entry - _mesa_extension_table;
 
-   return 0;
+   return -1;
 }
 
 /**
  * Overrides extensions in \c ctx based on the values in
  * _mesa_extension_override_enables and _mesa_extension_override_disables.
  */
-static void
-override_extensions_in_context(struct gl_context *ctx)
+void
+_mesa_override_extensions(struct gl_context *ctx)
 {
    unsigned i;
    const GLboolean *enables =
@@ -452,8 +100,8 @@ override_extensions_in_context(struct gl_context *ctx)
       (GLboolean*) &_mesa_extension_override_disables;
    GLboolean *ctx_ext = (GLboolean*)&ctx->Extensions;
 
-   for (i = 0; i < ARRAY_SIZE(extension_table); ++i) {
-      size_t offset = extension_table[i].offset;
+   for (i = 0; i < MESA_EXTENSION_COUNT; ++i) {
+      size_t offset = _mesa_extension_table[i].offset;
 
       assert(!enables[offset] || !disables[offset]);
       if (enables[offset]) {
@@ -494,9 +142,8 @@ _mesa_enable_sw_extensions(struct gl_context *ctx)
    ctx->Extensions.ARB_texture_env_combine = GL_TRUE;
    ctx->Extensions.ARB_texture_env_crossbar = GL_TRUE;
    ctx->Extensions.ARB_texture_env_dot3 = GL_TRUE;
-#ifdef TEXTURE_FLOAT_ENABLED
+   ctx->Extensions.ARB_texture_filter_anisotropic = GL_TRUE;
    ctx->Extensions.ARB_texture_float = GL_TRUE;
-#endif
    ctx->Extensions.ARB_texture_mirror_clamp_to_edge = GL_TRUE;
    ctx->Extensions.ARB_texture_non_power_of_two = GL_TRUE;
    ctx->Extensions.ARB_texture_rg = GL_TRUE;
@@ -509,7 +156,6 @@ _mesa_enable_sw_extensions(struct gl_context *ctx)
    ctx->Extensions.ATI_texture_compression_3dc = GL_TRUE;
    ctx->Extensions.ATI_texture_env_combine3 = GL_TRUE;
    ctx->Extensions.ATI_texture_mirror_once = GL_TRUE;
-   ctx->Extensions.ATI_separate_stencil = GL_TRUE;
    ctx->Extensions.EXT_blend_color = GL_TRUE;
    ctx->Extensions.EXT_blend_equation_separate = GL_TRUE;
    ctx->Extensions.EXT_blend_func_separate = GL_TRUE;
@@ -540,10 +186,8 @@ _mesa_enable_sw_extensions(struct gl_context *ctx)
    ctx->Extensions.EXT_gpu_program_parameters = GL_TRUE;
    ctx->Extensions.OES_standard_derivatives = GL_TRUE;
    ctx->Extensions.TDFX_texture_compression_FXT1 = GL_TRUE;
-   if (ctx->Mesa_DXTn) {
-      ctx->Extensions.ANGLE_texture_compression_dxt = GL_TRUE;
-      ctx->Extensions.EXT_texture_compression_s3tc = GL_TRUE;
-   }
+   ctx->Extensions.ANGLE_texture_compression_dxt = GL_TRUE;
+   ctx->Extensions.EXT_texture_compression_s3tc = GL_TRUE;
 }
 
 /**
@@ -551,11 +195,11 @@ _mesa_enable_sw_extensions(struct gl_context *ctx)
  * \return offset of extensions withint `ext' or 0 if extension is not known
  */
 static size_t
-set_extension(struct gl_extensions *ext, const char *name, GLboolean state)
+set_extension(struct gl_extensions *ext, int i, GLboolean state)
 {
    size_t offset;
 
-   offset = name_to_offset(name);
+   offset = i < 0 ? 0 : _mesa_extension_table[i].offset;
    if (offset != 0 && (offset != o(dummy_true) || state != GL_FALSE)) {
       ((GLboolean *) ext)[offset] = state;
    }
@@ -563,62 +207,33 @@ set_extension(struct gl_extensions *ext, const char *name, GLboolean state)
    return offset;
 }
 
-/**
- * \brief Apply the \c MESA_EXTENSION_OVERRIDE environment variable.
- *
- * \c MESA_EXTENSION_OVERRIDE is a space-separated list of extensions to
- * enable or disable. The list is processed thus:
- *    - Enable recognized extension names that are prefixed with '+'.
- *    - Disable recognized extension names that are prefixed with '-'.
- *    - Enable recognized extension names that are not prefixed.
- *    - Collect unrecognized extension names in a new string.
- *
- * \c MESA_EXTENSION_OVERRIDE was previously parsed during
- * _mesa_one_time_init_extension_overrides. We just use the results of that
- * parsing in this function.
- *
- * \return Space-separated list of unrecognized extension names (which must
- *    be freed). Does not return \c NULL.
- */
-static char *
-get_extension_override( struct gl_context *ctx )
-{
-   override_extensions_in_context(ctx);
-
-   if (cant_disable_extensions != NULL) {
-      _mesa_problem(ctx,
-                    "Trying to disable permanently enabled extensions: %s",
-                   cant_disable_extensions);
-   }
-
-   if (extra_extensions == NULL) {
-      return calloc(1, sizeof(char));
-   } else {
-      _mesa_problem(ctx, "Trying to enable unknown extensions: %s",
-                    extra_extensions);
-      return strdup(extra_extensions);
-   }
-}
-
 
 /**
- * \brief Free extra_extensions and cant_disable_extensions strings
+ * \brief Free string pointed by unrecognized_extensions
  *
- * These strings are allocated early during the first context creation by
+ * This string is allocated early during the first context creation by
  * _mesa_one_time_init_extension_overrides.
  */
 static void
 free_unknown_extensions_strings(void)
 {
-   free(extra_extensions);
-   free(cant_disable_extensions);
+   free(unrecognized_extensions.env);
+   for (int i = 0; i < MAX_UNRECOGNIZED_EXTENSIONS; ++i)
+      unrecognized_extensions.names[i] = NULL;
 }
 
 
 /**
- * \brief Initialize extension override tables.
+ * \brief Initialize extension override tables based on \c MESA_EXTENSION_OVERRIDE
  *
  * This should be called one time early during first context initialization.
+
+ * \c MESA_EXTENSION_OVERRIDE is a space-separated list of extensions to
+ * enable or disable. The list is processed thus:
+ *    - Enable recognized extension names that are prefixed with '+'.
+ *    - Disable recognized extension names that are prefixed with '-'.
+ *    - Enable recognized extension names that are not prefixed.
+ *    - Collect unrecognized extension names in a new string.
  */
 void
 _mesa_one_time_init_extension_overrides(void)
@@ -626,10 +241,8 @@ _mesa_one_time_init_extension_overrides(void)
    const char *env_const = getenv("MESA_EXTENSION_OVERRIDE");
    char *env;
    char *ext;
-   int len;
    size_t offset;
-
-   atexit(free_unknown_extensions_strings);
+   unsigned unknown_ext = 0;
 
    memset(&_mesa_extension_override_enables, 0, sizeof(struct gl_extensions));
    memset(&_mesa_extension_override_disables, 0, sizeof(struct gl_extensions));
@@ -638,23 +251,15 @@ _mesa_one_time_init_extension_overrides(void)
       return;
    }
 
-   /* extra_exts: List of unrecognized extensions. */
-   extra_extensions = calloc(ALIGN(strlen(env_const) + 2, 4), sizeof(char));
-   cant_disable_extensions = calloc(ALIGN(strlen(env_const) + 2, 4), sizeof(char));
-
    /* Copy env_const because strtok() is destructive. */
    env = strdup(env_const);
 
-   if (env == NULL || extra_extensions == NULL ||
-           cant_disable_extensions == NULL) {
-       free(env);
-       free(extra_extensions);
-       free(cant_disable_extensions);
-       return;
-   }
+   if (env == NULL)
+      return;
 
    for (ext = strtok(env, " "); ext != NULL; ext = strtok(NULL, " ")) {
       int enable;
+      int i;
       bool recognized;
       switch (ext[0]) {
       case '+':
@@ -670,41 +275,37 @@ _mesa_one_time_init_extension_overrides(void)
          break;
       }
 
-      offset = set_extension(&_mesa_extension_override_enables, ext, enable);
-      if (offset != 0 && (offset != o(dummy_true) || enable != GL_FALSE)) {
-         ((GLboolean *) &_mesa_extension_override_disables)[offset] = !enable;
+      i = name_to_index(ext);
+      offset = set_extension(&_mesa_extension_override_enables, i, enable);
+      offset = set_extension(&_mesa_extension_override_disables, i, !enable);
+      if (offset != 0)
          recognized = true;
-      } else {
+      else
          recognized = false;
-      }
 
-      if (!recognized) {
-         if (enable) {
-            strcat(extra_extensions, ext);
-            strcat(extra_extensions, " ");
-         } else if (offset == o(dummy_true)) {
-            strcat(cant_disable_extensions, ext);
-            strcat(cant_disable_extensions, " ");
+      if (!recognized && enable) {
+         if (unknown_ext >= MAX_UNRECOGNIZED_EXTENSIONS) {
+            static bool warned;
+
+            if (!warned) {
+               warned = true;
+               _mesa_problem(NULL, "Trying to enable too many unknown extension. "
+                                   "Only the first %d will be honoured",
+                                   MAX_UNRECOGNIZED_EXTENSIONS);
+            }
+         } else {
+            unrecognized_extensions.names[unknown_ext] = ext;
+            unknown_ext++;
+            _mesa_problem(NULL, "Trying to enable unknown extension: %s", ext);
          }
       }
    }
 
-   free(env);
-
-   /* Remove trailing space, and free if unused. */
-   len = strlen(extra_extensions);
-   if (len == 0) {
-      free(extra_extensions);
-      extra_extensions = NULL;
-   } else if (extra_extensions[len - 1] == ' ') {
-      extra_extensions[len - 1] = '\0';
-   }
-   len = strlen(cant_disable_extensions);
-   if (len == 0) {
-      free(cant_disable_extensions);
-      cant_disable_extensions = NULL;
-   } else if (cant_disable_extensions[len - 1] == ' ') {
-      cant_disable_extensions[len - 1] = '\0';
+   if (!unknown_ext) {
+      free(env);
+   } else {
+      unrecognized_extensions.env = env;
+      atexit(free_unknown_extensions_strings);
    }
 }
 
@@ -728,26 +329,40 @@ _mesa_init_extensions(struct gl_extensions *extensions)
 
    /* Then, selectively turn default extensions on. */
    extensions->dummy_true = GL_TRUE;
-   extensions->EXT_texture3D = GL_TRUE;
 }
 
 
 typedef unsigned short extension_index;
 
 
+/**
+ * Given an extension enum, return whether or not the extension is supported
+ * dependent on the following factors:
+ * There's driver support and the OpenGL/ES version is at least that
+ * specified in the _mesa_extension_table.
+ */
+static inline bool
+_mesa_extension_supported(const struct gl_context *ctx, extension_index i)
+{
+   const bool *base = (bool *) &ctx->Extensions;
+   const struct mesa_extension *ext = _mesa_extension_table + i;
+
+   return (ctx->Version >= ext->version[ctx->API]) && base[ext->offset];
+}
+
 /**
  * Compare two entries of the extensions table.  Sorts first by year,
  * then by name.
  *
- * Arguments are indices into extension_table.
+ * Arguments are indices into _mesa_extension_table.
  */
 static int
 extension_compare(const void *p1, const void *p2)
 {
    extension_index i1 = * (const extension_index *) p1;
    extension_index i2 = * (const extension_index *) p2;
-   const struct extension *e1 = &extension_table[i1];
-   const struct extension *e2 = &extension_table[i2];
+   const struct mesa_extension *e1 = &_mesa_extension_table[i1];
+   const struct mesa_extension *e2 = &_mesa_extension_table[i2];
    int res;
 
    res = (int)e1->year - (int)e2->year;
@@ -774,18 +389,10 @@ _mesa_make_extension_string(struct gl_context *ctx)
    /* Number of extensions */
    unsigned count;
    /* Indices of the extensions sorted by year */
-   extension_index *extension_indices;
-   /* String of extra extensions. */
-   char *extra_extensions = get_extension_override(ctx);
-   GLboolean *base = (GLboolean *) &ctx->Extensions;
+   extension_index extension_indices[MESA_EXTENSION_COUNT];
    unsigned k;
    unsigned j;
    unsigned maxYear = ~0;
-   unsigned api_set = (1 << ctx->API);
-   if (_mesa_is_gles3(ctx))
-      api_set |= ES3;
-   if (_mesa_is_gles31(ctx))
-      api_set |= ES31;
 
    /* Check if the MESA_EXTENSION_MAX_YEAR env var is set */
    {
@@ -799,44 +406,35 @@ _mesa_make_extension_string(struct gl_context *ctx)
 
    /* Compute length of the extension string. */
    count = 0;
-   for (k = 0; k < ARRAY_SIZE(extension_table); ++k) {
-      const struct extension *i = extension_table + k;
+   for (k = 0; k < MESA_EXTENSION_COUNT; ++k) {
+      const struct mesa_extension *i = _mesa_extension_table + k;
 
-      if (base[i->offset] &&
-          i->year <= maxYear &&
-          (i->api_set & api_set)) {
+      if (i->year <= maxYear &&
+          _mesa_extension_supported(ctx, k)) {
         length += strlen(i->name) + 1; /* +1 for space */
         ++count;
       }
    }
-   if (extra_extensions != NULL)
-      length += 1 + strlen(extra_extensions); /* +1 for space */
+   for (k = 0; k < MAX_UNRECOGNIZED_EXTENSIONS; k++)
+      if (unrecognized_extensions.names[k])
+         length += 1 + strlen(unrecognized_extensions.names[k]); /* +1 for space */
 
    exts = calloc(ALIGN(length + 1, 4), sizeof(char));
    if (exts == NULL) {
-      free(extra_extensions);
-      return NULL;
-   }
-
-   extension_indices = malloc(count * sizeof(extension_index));
-   if (extension_indices == NULL) {
-      free(exts);
-      free(extra_extensions);
       return NULL;
    }
 
-   /* Sort extensions in chronological order because certain old applications
-    * (e.g., Quake3 demo) store the extension list in a static size buffer so
-    * chronologically order ensure that the extensions that such applications
-    * expect will fit into that buffer.
+   /* Sort extensions in chronological order because idTech 2/3 games
+    * (e.g., Quake3 demo) store the extension list in a fixed size buffer.
+    * Some cases truncate, while others overflow the buffer. Resulting in
+    * misrendering and crashes, respectively.
+    * Address the former here, while the latter will be addressed by setting
+    * the MESA_EXTENSION_MAX_YEAR environment variable.
     */
    j = 0;
-   for (k = 0; k < ARRAY_SIZE(extension_table); ++k) {
-      const struct extension *i = extension_table + k;
-
-      if (base[i->offset] &&
-          i->year <= maxYear &&
-          (i->api_set & api_set)) {
+   for (k = 0; k < MESA_EXTENSION_COUNT; ++k) {
+      if (_mesa_extension_table[k].year <= maxYear &&
+         _mesa_extension_supported(ctx, k)) {
          extension_indices[j++] = k;
       }
    }
@@ -846,15 +444,16 @@ _mesa_make_extension_string(struct gl_context *ctx)
 
    /* Build the extension string.*/
    for (j = 0; j < count; ++j) {
-      const struct extension *i = &extension_table[extension_indices[j]];
-      assert(base[i->offset] && (i->api_set & api_set));
+      const struct mesa_extension *i = &_mesa_extension_table[extension_indices[j]];
+      assert(_mesa_extension_supported(ctx, extension_indices[j]));
       strcat(exts, i->name);
       strcat(exts, " ");
    }
-   free(extension_indices);
-   if (extra_extensions != 0) {
-      strcat(exts, extra_extensions);
-      free(extra_extensions);
+   for (j = 0; j < MAX_UNRECOGNIZED_EXTENSIONS; j++) {
+      if (unrecognized_extensions.names[j]) {
+         strcat(exts, unrecognized_extensions.names[j]);
+         strcat(exts, " ");
+      }
    }
 
    return (GLubyte *) exts;
@@ -866,25 +465,20 @@ _mesa_make_extension_string(struct gl_context *ctx)
 GLuint
 _mesa_get_extension_count(struct gl_context *ctx)
 {
-   GLboolean *base;
    unsigned k;
-   unsigned api_set = (1 << ctx->API);
-   if (_mesa_is_gles3(ctx))
-      api_set |= ES3;
-   if (_mesa_is_gles31(ctx))
-      api_set |= ES31;
 
    /* only count once */
    if (ctx->Extensions.Count != 0)
       return ctx->Extensions.Count;
 
-   base = (GLboolean *) &ctx->Extensions;
-   for (k = 0; k < ARRAY_SIZE(extension_table); ++k) {
-      const struct extension *i = extension_table + k;
-
-      if (base[i->offset] && (i->api_set & api_set)) {
+   for (k = 0; k < MESA_EXTENSION_COUNT; ++k) {
+      if (_mesa_extension_supported(ctx, k))
         ctx->Extensions.Count++;
-      }
+   }
+
+   for (k = 0; k < MAX_UNRECOGNIZED_EXTENSIONS; ++k) {
+      if (unrecognized_extensions.names[k])
+         ctx->Extensions.Count++;
    }
    return ctx->Extensions.Count;
 }
@@ -895,27 +489,25 @@ _mesa_get_extension_count(struct gl_context *ctx)
 const GLubyte *
 _mesa_get_enabled_extension(struct gl_context *ctx, GLuint index)
 {
-   const GLboolean *base;
-   size_t n;
-   unsigned k;
-   unsigned api_set = (1 << ctx->API);
-   if (_mesa_is_gles3(ctx))
-      api_set |= ES3;
-   if (_mesa_is_gles31(ctx))
-      api_set |= ES31;
-
-   base = (GLboolean*) &ctx->Extensions;
-   n = 0;
-   for (k = 0; k < ARRAY_SIZE(extension_table); ++k) {
-      const struct extension *i = extension_table + k;
-
-      if (base[i->offset] && (i->api_set & api_set)) {
+   size_t n = 0;
+   unsigned i;
+
+   for (i = 0; i < MESA_EXTENSION_COUNT; ++i) {
+      if (_mesa_extension_supported(ctx, i)) {
          if (n == index)
-            return (const GLubyte*) i->name;
+            return (const GLubyte*) _mesa_extension_table[i].name;
          else
             ++n;
       }
    }
 
+   for (i = 0; i < MAX_UNRECOGNIZED_EXTENSIONS; ++i) {
+      if (unrecognized_extensions.names[i]) {
+         if (n == index)
+            return (const GLubyte*) unrecognized_extensions.names[i];
+         else
+            ++n;
+      }
+   }
    return NULL;
 }