diff --git a/api/opencl_architecture.asciidoc b/api/opencl_architecture.asciidoc
index 2e559530..57cc2c17 100644
--- a/api/opencl_architecture.asciidoc
+++ b/api/opencl_architecture.asciidoc
@@ -2263,6 +2263,25 @@ typedef cl_uint cl_version;
     ((patch) & CL_VERSION_PATCH_MASK))
 ----
 
+[NOTE]
+--
+The available version of an extension is exposed to the user via a macro
+defined by the OpenCL Headers. This macro takes the format of the uppercase
+extension name followed by the `_EXTENSION_VERSION` suffix. For example,
+`CL_KHR_SEMAPHORE_EXTENSION_VERSION` is the macro defining the version of the
+{cl_khr_semaphore_EXT} extension.
+
+The value of this macro is set to the {cl_version_TYPE} of the extension using
+the semantic version of the extension. If no semantic version is defined for
+the extension, then the value of the macro is set to `0` to represent semantic
+version `0.0.0`.
+
+Applications can use these version macros along with the convience macros
+defined in this section to guard their code against breaking changes to the API
+of extensions, in particular provisional KHR extensions which have yet to
+finalize an API.
+--
+
 [[version-name-pairing]]
 ==== Version-Name Pairing
 
diff --git a/xml/cl.xml b/xml/cl.xml
index 7700355a..bca2621d 100644
--- a/xml/cl.xml
+++ b/xml/cl.xml
@@ -5389,7 +5389,7 @@ server's OpenCL/api-docs repository.
 
     <!-- SECTION: OpenCL extension interface definitions -->
     <extensions>
-        <extension name="cl_khr_d3d10_sharing" supported="opencl" ratified="opencl">
+        <extension name="cl_khr_d3d10_sharing" revision="1.0.0" supported="opencl" ratified="opencl">
             <require>
                 <type name="d3d10.h"/>
                 <type name="CL/cl.h"/>
@@ -5436,7 +5436,7 @@ server's OpenCL/api-docs repository.
                 <command name="clEnqueueReleaseD3D10ObjectsKHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_d3d11_sharing" supported="opencl" ratified="opencl">
+        <extension name="cl_khr_d3d11_sharing" revision="1.0.0" supported="opencl" ratified="opencl">
             <require>
                 <type name="d3d11.h"/>
                 <type name="CL/cl.h"/>
@@ -5483,7 +5483,7 @@ server's OpenCL/api-docs repository.
                 <command name="clEnqueueReleaseD3D11ObjectsKHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_dx9_media_sharing" supported="opencl" ratified="opencl">
+        <extension name="cl_khr_dx9_media_sharing" revision="1.0.0" supported="opencl" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5532,7 +5532,7 @@ server's OpenCL/api-docs repository.
                 <command name="clEnqueueReleaseDX9MediaSurfacesKHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_egl_image" supported="opencl" ratified="opencl">
+        <extension name="cl_khr_egl_image" revision="1.0.0" supported="opencl" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5560,7 +5560,7 @@ server's OpenCL/api-docs repository.
                 <command name="clEnqueueReleaseEGLObjectsKHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_egl_event" supported="opencl" ratified="opencl">
+        <extension name="cl_khr_egl_event" revision="1.0.0" supported="opencl" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5574,7 +5574,7 @@ server's OpenCL/api-docs repository.
                 <command name="clCreateEventFromEGLSyncKHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_fp64" supported="opencl" promotedto="CL_VERSION_1_2" ratified="opencl">
+        <extension name="cl_khr_fp64" revision="1.0.0" supported="opencl" promotedto="CL_VERSION_1_2" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5582,7 +5582,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_DEVICE_DOUBLE_FP_CONFIG"/>
             </require>
         </extension>
-        <extension name="cl_khr_fp16" supported="opencl" ratified="opencl">
+        <extension name="cl_khr_fp16" revision="1.0.0" supported="opencl" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5590,7 +5590,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_DEVICE_HALF_FP_CONFIG"/>
             </require>
         </extension>
-        <extension name="cl_APPLE_SetMemObjectDestructor" comment="not registered" supported="opencl">
+        <extension name="cl_APPLE_SetMemObjectDestructor" revision="0.0.0" comment="not registered" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5598,7 +5598,7 @@ server's OpenCL/api-docs repository.
                 <command name="clSetMemObjectDestructorAPPLE"/>
             </require>
         </extension>
-        <extension name="cl_APPLE_ContextLoggingFunctions" comment="not registered" supported="opencl">
+        <extension name="cl_APPLE_ContextLoggingFunctions" revision="0.0.0" comment="not registered" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5608,7 +5608,7 @@ server's OpenCL/api-docs repository.
                 <command name="clLogMessagesToStderrAPPLE"/>
             </require>
         </extension>
-        <extension name="cl_khr_icd" supported="opencl" ratified="opencl">
+        <extension name="cl_khr_icd" revision="1.0.0" supported="opencl" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5622,7 +5622,7 @@ server's OpenCL/api-docs repository.
                 <command name="clIcdGetPlatformIDsKHR"/>
             </require>
         </extension>
-        <extension name="cl_loader_layers" supported="opencl">
+        <extension name="cl_loader_layers" revision="1.0.0" supported="opencl">
             <require>
                 <type name="CL/cl_icd.h"/>
             </require>
@@ -5642,7 +5642,7 @@ server's OpenCL/api-docs repository.
                 <command name="clInitLayer"/>
             </require>
         </extension>
-        <extension name="cl_loader_info" supported="opencl">
+        <extension name="cl_loader_info" revision="1.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5659,7 +5659,7 @@ server's OpenCL/api-docs repository.
                 <command name="clGetICDLoaderInfoOCLICD"/>
             </require>
         </extension>
-        <extension name="cl_khr_il_program" supported="opencl" promotedto="CL_VERSION_2_1" ratified="opencl">
+        <extension name="cl_khr_il_program" revision="1.0.0" supported="opencl" promotedto="CL_VERSION_2_1" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5673,13 +5673,13 @@ server's OpenCL/api-docs repository.
                 <command name="clCreateProgramWithILKHR" comment="No EXT_SUFFIX?"/>
             </require>
         </extension>
-        <extension name="cl_khr_image2d_from_buffer" supported="opencl" promotedto="CL_VERSION_2_0" ratified="opencl">
+        <extension name="cl_khr_image2d_from_buffer" revision="1.0.0" supported="opencl" promotedto="CL_VERSION_2_0" ratified="opencl">
             <require comment="cl_device_info">
                 <enum name="CL_DEVICE_IMAGE_PITCH_ALIGNMENT_KHR"/>
                 <enum name="CL_DEVICE_IMAGE_BASE_ADDRESS_ALIGNMENT_KHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_initialize_memory" supported="opencl" ratified="opencl">
+        <extension name="cl_khr_initialize_memory" revision="1.0.0" supported="opencl" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5694,7 +5694,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_CONTEXT_MEMORY_INITIALIZE_PRIVATE_KHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_terminate_context" supported="opencl" ratified="opencl">
+        <extension name="cl_khr_terminate_context" revision="1.0.0" supported="opencl" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5717,7 +5717,7 @@ server's OpenCL/api-docs repository.
                 <command name="clTerminateContextKHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_spir" supported="opencl" obsoletedby="cl_khr_il_program" ratified="opencl">
+        <extension name="cl_khr_spir" revision="1.0.0" supported="opencl" obsoletedby="cl_khr_il_program" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5728,7 +5728,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_PROGRAM_BINARY_TYPE_INTERMEDIATE"/>
             </require>
         </extension>
-        <extension name="cl_khr_create_command_queue" supported="opencl" promotedto="CL_VERSION_2_0" ratified="opencl">
+        <extension name="cl_khr_create_command_queue" revision="1.0.0" supported="opencl" promotedto="CL_VERSION_2_0" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5739,7 +5739,7 @@ server's OpenCL/api-docs repository.
                 <command name="clCreateCommandQueueWithPropertiesKHR"/>
             </require>
         </extension>
-        <extension name="cl_nv_device_attribute_query" supported="opencl">
+        <extension name="cl_nv_device_attribute_query" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5753,7 +5753,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_DEVICE_INTEGRATED_MEMORY_NV"/>
             </require>
         </extension>
-        <extension name="cl_amd_device_attribute_query" supported="opencl">
+        <extension name="cl_amd_device_attribute_query" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5781,7 +5781,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_DEVICE_PCIE_ID_AMD"/>
             </require>
         </extension>
-        <extension name="cl_arm_printf" supported="opencl">
+        <extension name="cl_arm_printf" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5790,7 +5790,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_PRINTF_BUFFERSIZE_ARM"/>
             </require>
         </extension>
-        <extension name="cl_ext_device_fission" supported="opencl">
+        <extension name="cl_ext_device_fission" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5834,7 +5834,7 @@ server's OpenCL/api-docs repository.
                 <command name="clCreateSubDevicesEXT"/>
             </require>
         </extension>
-        <extension name="cl_ext_migrate_memobject" supported="opencl">
+        <extension name="cl_ext_migrate_memobject" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5851,7 +5851,7 @@ server's OpenCL/api-docs repository.
                 <command name="clEnqueueMigrateMemObjectEXT"/>
             </require>
         </extension>
-        <extension name="cl_qcom_ext_host_ptr" supported="opencl">
+        <extension name="cl_qcom_ext_host_ptr" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5880,7 +5880,7 @@ server's OpenCL/api-docs repository.
                 <command name="clGetDeviceImageInfoQCOM"/>
             </require>
         </extension>
-        <extension name="cl_qcom_ext_host_ptr_iocoherent" supported="opencl">
+        <extension name="cl_qcom_ext_host_ptr_iocoherent" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5888,7 +5888,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_MEM_HOST_IOCOHERENT_QCOM"/>
             </require>
         </extension>
-        <extension name="cl_qcom_ion_host_ptr" supported="opencl">
+        <extension name="cl_qcom_ion_host_ptr" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5900,7 +5900,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_MEM_ION_HOST_PTR_QCOM"/>
             </require>
         </extension>
-        <extension name="cl_qcom_android_native_buffer_host_ptr" supported="opencl">
+        <extension name="cl_qcom_android_native_buffer_host_ptr" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5912,7 +5912,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_MEM_ANDROID_NATIVE_BUFFER_HOST_PTR_QCOM"/>
             </require>
         </extension>
-        <extension name="cl_img_yuv_image" supported="opencl">
+        <extension name="cl_img_yuv_image" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5921,7 +5921,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_YV12_IMG"/>
             </require>
         </extension>
-        <extension name="cl_img_cached_allocations" supported="opencl">
+        <extension name="cl_img_cached_allocations" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5930,7 +5930,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_MEM_USE_CACHED_CPU_MEMORY_IMG"/>
             </require>
         </extension>
-        <extension name="cl_khr_mipmap_image" supported="opencl" ratified="opencl">
+        <extension name="cl_khr_mipmap_image" revision="1.0.0" supported="opencl" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5940,7 +5940,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_SAMPLER_LOD_MAX_KHR"/>
             </require>
         </extension>
-        <extension name="cl_img_use_gralloc_ptr" supported="opencl">
+        <extension name="cl_img_use_gralloc_ptr" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5960,7 +5960,7 @@ server's OpenCL/api-docs repository.
                 <command name="clEnqueueReleaseGrallocObjectsIMG"/>
             </require>
         </extension>
-        <extension name="cl_khr_subgroups" supported="opencl" promotedto="CL_VERSION_2_1" ratified="opencl">
+        <extension name="cl_khr_subgroups" revision="1.0.0" supported="opencl" promotedto="CL_VERSION_2_1" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5975,7 +5975,7 @@ server's OpenCL/api-docs repository.
                 <command name="clGetKernelSubGroupInfoKHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_priority_hints" supported="opencl" ratified="opencl">
+        <extension name="cl_khr_priority_hints" revision="1.0.0" supported="opencl" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -5991,7 +5991,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_QUEUE_PRIORITY_LOW_KHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_throttle_hints" supported="opencl" ratified="opencl">
+        <extension name="cl_khr_throttle_hints" revision="1.0.0" supported="opencl" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -6007,7 +6007,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_QUEUE_THROTTLE_LOW_KHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_subgroup_named_barrier" supported="opencl" ratified="opencl">
+        <extension name="cl_khr_subgroup_named_barrier" revision="1.0.0" supported="opencl" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -6015,7 +6015,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_DEVICE_MAX_NAMED_BARRIER_COUNT_KHR"/>
             </require>
         </extension>
-        <extension name="cl_arm_import_memory" supported="opencl">
+        <extension name="cl_arm_import_memory" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -6053,7 +6053,7 @@ server's OpenCL/api-docs repository.
                 <command name="clImportMemoryARM"/>
             </require>
         </extension>
-        <extension name="cl_arm_shared_virtual_memory" supported="opencl">
+        <extension name="cl_arm_shared_virtual_memory" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -6101,7 +6101,7 @@ server's OpenCL/api-docs repository.
                 <command name="clSetKernelExecInfoARM"/>
             </require>
         </extension>
-        <extension name="cl_arm_get_core_id" condition="defined(CL_VERSION_1_2)" supported="opencl">
+        <extension name="cl_arm_get_core_id" revision="0.0.0" condition="defined(CL_VERSION_1_2)" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -6109,7 +6109,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_DEVICE_COMPUTE_UNITS_BITFIELD_ARM"/>
             </require>
         </extension>
-        <extension name="cl_intel_exec_by_local_thread" supported="opencl">
+        <extension name="cl_intel_exec_by_local_thread" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
                 <type name="CL/cl_platform.h"/>
@@ -6118,13 +6118,13 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_QUEUE_THREAD_LOCAL_EXEC_ENABLE_INTEL"/>
             </require>
         </extension>
-        <extension name="cl_intel_device_partition_by_names" supported="opencl">
+        <extension name="cl_intel_device_partition_by_names" revision="0.0.0" supported="opencl">
             <require>
                 <enum name="CL_DEVICE_PARTITION_BY_NAMES_INTEL"/>
                 <enum name="CL_PARTITION_BY_NAMES_LIST_END_INTEL"/>
             </require>
         </extension>
-        <extension name="cl_intel_accelerator" supported="opencl">
+        <extension name="cl_intel_accelerator" revision="0.0.0" supported="opencl">
             <require>
                 <type name="cl_accelerator_intel"/>
                 <type name="cl_accelerator_type_intel"/>
@@ -6149,7 +6149,7 @@ server's OpenCL/api-docs repository.
                 <command name="clReleaseAcceleratorINTEL"/>
             </require>
         </extension>
-        <extension name="cl_intel_motion_estimation" supported="opencl">
+        <extension name="cl_intel_motion_estimation" revision="0.0.0" supported="opencl">
             <require>
                 <type name="cl_motion_estimation_desc_intel"/>
             </require>
@@ -6176,7 +6176,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_ME_SEARCH_PATH_RADIUS_16_12_INTEL"/>
             </require>
         </extension>
-        <extension name="cl_intel_advanced_motion_estimation" supported="opencl">
+        <extension name="cl_intel_advanced_motion_estimation" revision="0.0.0" supported="opencl">
             <require comment="cl_device_info">
                 <enum name="CL_DEVICE_ME_VERSION_INTEL"/>
             </require>
@@ -6236,18 +6236,18 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_ME_BIDIR_WEIGHT_THREE_QUARTER_INTEL"/>
             </require>
         </extension>
-        <extension name="cl_intel_simultaneous_sharing" supported="opencl">
+        <extension name="cl_intel_simultaneous_sharing" revision="0.0.0" supported="opencl">
             <require comment="cl_device_info">
                 <enum name="CL_DEVICE_SIMULTANEOUS_INTEROPS_INTEL"/>
                 <enum name="CL_DEVICE_NUM_SIMULTANEOUS_INTEROPS_INTEL"/>
             </require>
         </extension>
-        <extension name="cl_intel_egl_image_yuv" supported="opencl">
+        <extension name="cl_intel_egl_image_yuv" revision="0.0.0" supported="opencl">
             <require comment="cl_egl_image_properties_khr">
                 <enum name="CL_EGL_YUV_PLANE_INTEL"/>
             </require>
         </extension>
-        <extension name="cl_intel_packed_yuv" supported="opencl">
+        <extension name="cl_intel_packed_yuv" revision="0.0.0" supported="opencl">
             <require comment="cl_channel_order">
                 <enum name="CL_YUYV_INTEL"/>
                 <enum name="CL_UYVY_INTEL"/>
@@ -6255,7 +6255,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_VYUY_INTEL"/>
             </require>
         </extension>
-        <extension name="cl_intel_required_subgroup_size" supported="opencl">
+        <extension name="cl_intel_required_subgroup_size" revision="0.0.0" supported="opencl">
             <require comment="cl_device_info">
                 <enum name="CL_DEVICE_SUB_GROUP_SIZES_INTEL"/>
             </require>
@@ -6266,7 +6266,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_KERNEL_COMPILE_SUB_GROUP_SIZE_INTEL"/>
             </require>
         </extension>
-        <extension name="cl_intel_driver_diagnostics" supported="opencl">
+        <extension name="cl_intel_driver_diagnostics" revision="0.0.0" supported="opencl">
             <require>
                 <type name="cl_diagnostics_verbose_level"/>
             </require>
@@ -6278,7 +6278,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_CONTEXT_DIAGNOSTICS_LEVEL_NEUTRAL_INTEL"/>
             </require>
         </extension>
-        <extension name="cl_intel_planar_yuv" supported="opencl">
+        <extension name="cl_intel_planar_yuv" revision="0.0.0" supported="opencl">
             <require comment="cl_channel_order">
                 <enum name="CL_NV12_INTEL"/>
             </require>
@@ -6291,7 +6291,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_DEVICE_PLANAR_YUV_MAX_HEIGHT_INTEL"/>
             </require>
         </extension>
-        <extension name="cl_intel_device_side_avc_motion_estimation" supported="opencl">
+        <extension name="cl_intel_device_side_avc_motion_estimation" revision="0.0.0" supported="opencl">
             <require comment="cl_device_info">
                 <enum name="CL_DEVICE_AVC_ME_VERSION_INTEL"/>
                 <enum name="CL_DEVICE_AVC_ME_SUPPORTS_TEXTURE_SAMPLER_USE_INTEL"/>
@@ -6443,7 +6443,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_AVC_ME_INTERLACED_SCAN_BOTTOM_FIELD_INTEL"/>
             </require>
         </extension>
-        <extension name="cl_khr_gl_event" supported="opencl" depends="cl_khr_gl_sharing" ratified="opencl">
+        <extension name="cl_khr_gl_event" revision="1.0.0" supported="opencl" depends="cl_khr_gl_sharing" ratified="opencl">
             <require>
                 <type name="cl_GLsync"/>
             </require>
@@ -6454,7 +6454,7 @@ server's OpenCL/api-docs repository.
                 <command name="clCreateEventFromGLsyncKHR"/>
             </require>
         </extension>
-        <extension name="cl_intel_va_api_media_sharing" supported="opencl">
+        <extension name="cl_intel_va_api_media_sharing" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -6495,7 +6495,7 @@ server's OpenCL/api-docs repository.
                 <command name="clEnqueueReleaseVA_APIMediaSurfacesINTEL"/>
             </require>
         </extension>
-        <extension name="cl_intel_dx9_media_sharing" supported="opencl">
+        <extension name="cl_intel_dx9_media_sharing" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -6541,7 +6541,7 @@ server's OpenCL/api-docs repository.
                 <command name="clEnqueueReleaseDX9ObjectsINTEL"/>
             </require>
         </extension>
-        <extension name="cl_khr_gl_depth_images" depends="cl_khr_gl_sharing" comment="no API - reuses tokens from core API" supported="opencl" ratified="opencl">
+        <extension name="cl_khr_gl_depth_images" revision="1.0.0" depends="cl_khr_gl_sharing" comment="no API - reuses tokens from core API" supported="opencl" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -6552,7 +6552,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_UNORM_INT24"/>
             </require>
         </extension>
-        <extension name="cl_khr_gl_msaa_sharing" depends="cl_khr_gl_depth_images+cl_khr_gl_sharing" comment="no API - reuses tokens from core API" supported="opencl" ratified="opencl">
+        <extension name="cl_khr_gl_msaa_sharing" revision="1.0.0" depends="cl_khr_gl_depth_images+cl_khr_gl_sharing" comment="no API - reuses tokens from core API" supported="opencl" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -6562,7 +6562,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_GL_NUM_SAMPLES"/>
             </require>
         </extension>
-        <extension name="cl_khr_gl_sharing" supported="opencl" ratified="opencl">
+        <extension name="cl_khr_gl_sharing" revision="1.0.0" supported="opencl" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -6623,7 +6623,7 @@ server's OpenCL/api-docs repository.
                 <command name="clCreateFromGLTexture3D"/>
             </require>
         </extension>
-        <extension name="cl_intel_unified_shared_memory" comment="in sync with rev 1.0.0" supported="opencl">
+        <extension name="cl_intel_unified_shared_memory" revision="0.0.0" comment="in sync with rev 1.0.0" supported="opencl">
             <require>
                 <type name="cl_device_unified_shared_memory_capabilities_intel"/>
                 <type name="cl_mem_properties_intel"/>
@@ -6696,7 +6696,7 @@ server's OpenCL/api-docs repository.
                 <command name="clEnqueueMemsetINTEL"/>
             </require>
         </extension>
-        <extension name="cl_khr_device_uuid" supported="opencl" ratified="opencl">
+        <extension name="cl_khr_device_uuid" revision="1.0.0" supported="opencl" ratified="opencl">
             <require comment="Size Constants">
                 <enum name="CL_UUID_SIZE_KHR"/>
                 <enum name="CL_LUID_SIZE_KHR"/>
@@ -6709,7 +6709,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_DEVICE_NODE_MASK_KHR"/>
             </require>
         </extension>
-        <extension name="cl_intel_create_buffer_with_properties" supported="opencl">
+        <extension name="cl_intel_create_buffer_with_properties" revision="0.0.0" supported="opencl">
             <require>
                 <type name="cl_mem_properties_intel"/>
             </require>
@@ -6717,12 +6717,12 @@ server's OpenCL/api-docs repository.
                 <command name="clCreateBufferWithPropertiesINTEL"/>
             </require>
         </extension>
-        <extension name="cl_intel_mem_channel_property" supported="opencl">
+        <extension name="cl_intel_mem_channel_property" revision="0.0.0" supported="opencl">
             <require comment="cl_mem_properties_intel">
                 <enum name="CL_MEM_CHANNEL_INTEL"/>
             </require>
         </extension>
-        <extension name="cl_intel_mem_alloc_buffer_location" supported="opencl">
+        <extension name="cl_intel_mem_alloc_buffer_location" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -6733,7 +6733,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_MEM_ALLOC_BUFFER_LOCATION_INTEL"/>
             </require>
         </extension>
-        <extension name="cl_arm_scheduling_controls" supported="opencl">
+        <extension name="cl_arm_scheduling_controls" revision="0.0.0" supported="opencl">
             <require comment="Types">
                 <type name="cl_device_scheduling_controls_capabilities_arm"/>
             </require>
@@ -6767,17 +6767,17 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_QUEUE_COMPUTE_UNIT_LIMIT_ARM"/>
             </require>
         </extension>
-        <extension name="cl_ext_cxx_for_opencl" supported="opencl">
+        <extension name="cl_ext_cxx_for_opencl" revision="0.0.0" supported="opencl">
             <require comment="cl_device_info">
                 <enum name="CL_DEVICE_CXX_FOR_OPENCL_NUMERIC_VERSION_EXT"/>
             </require>
         </extension>
-        <extension name="cl_intel_mem_force_host_memory" supported="opencl">
+        <extension name="cl_intel_mem_force_host_memory" revision="0.0.0" supported="opencl">
             <require comment="cl_mem_flags">
                 <enum name="CL_MEM_FORCE_HOST_MEMORY_INTEL"/>
             </require>
         </extension>
-        <extension name="cl_khr_depth_images" supported="opencl" promotedto="CL_VERSION_2_0" ratified="opencl">
+        <extension name="cl_khr_depth_images" revision="1.0.0" supported="opencl" promotedto="CL_VERSION_2_0" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -6785,7 +6785,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_DEPTH"/>
             </require>
         </extension>
-        <extension name="cl_khr_extended_versioning" supported="opencl" promotedto="CL_VERSION_3_0" ratified="opencl">
+        <extension name="cl_khr_extended_versioning" revision="1.0.0" supported="opencl" promotedto="CL_VERSION_3_0" ratified="opencl">
             <require>
                 <enum name="CL_VERSION_MAJOR_BITS_KHR"/>
                 <enum name="CL_VERSION_MINOR_BITS_KHR"/>
@@ -6823,7 +6823,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_DEVICE_BUILT_IN_KERNELS_WITH_VERSION_KHR"/>
             </require>
         </extension>
-        <extension name="cl_img_generate_mipmap" supported="opencl">
+        <extension name="cl_img_generate_mipmap" revision="0.0.0" supported="opencl">
             <require>
                 <type name="cl_mipmap_filter_mode_img"/>
             </require>
@@ -6838,7 +6838,7 @@ server's OpenCL/api-docs repository.
                 <command name="clEnqueueGenerateMipmapIMG"/>
             </require>
         </extension>
-        <extension name="cl_img_mem_properties" supported="opencl">
+        <extension name="cl_img_mem_properties" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -6857,7 +6857,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_DEVICE_MEMORY_CAPABILITIES_IMG"/>
             </require>
         </extension>
-        <extension name="cl_arm_controlled_kernel_termination" supported="opencl">
+        <extension name="cl_arm_controlled_kernel_termination" revision="0.0.0" supported="opencl">
             <require comment="Types">
                 <type name="cl_device_controlled_termination_capabilities_arm"/>
             </require>
@@ -6882,7 +6882,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_COMMAND_TERMINATION_ERROR_ARM"/>
             </require>
         </extension>
-        <extension name="cl_intel_command_queue_families" supported="opencl">
+        <extension name="cl_intel_command_queue_families" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -6922,7 +6922,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_QUEUE_CAPABILITY_KERNEL_INTEL"/>
             </require>
         </extension>
-        <extension name="cl_khr_pci_bus_info" supported="opencl" ratified="opencl">
+        <extension name="cl_khr_pci_bus_info" revision="1.0.0" supported="opencl" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -6933,7 +6933,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_DEVICE_PCI_BUS_INFO_KHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_suggested_local_work_size" supported="opencl" ratified="opencl">
+        <extension name="cl_khr_suggested_local_work_size" revision="1.0.0" supported="opencl" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -6941,7 +6941,7 @@ server's OpenCL/api-docs repository.
                 <command name="clGetKernelSuggestedLocalWorkSizeKHR"/>
             </require>
         </extension>
-        <extension name="cl_intel_device_attribute_query" supported="opencl">
+        <extension name="cl_intel_device_attribute_query" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -6980,7 +6980,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_DEVICE_INTEGER_DOT_PRODUCT_ACCELERATION_PROPERTIES_4x8BIT_PACKED_KHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_semaphore" revision="0.9.1" supported="opencl" depends="CL_VERSION_1_2" ratified="opencl">
+        <extension name="cl_khr_semaphore" revision="1.0.0" supported="opencl" depends="CL_VERSION_1_2" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -7027,7 +7027,7 @@ server's OpenCL/api-docs repository.
                 <command name="clRetainSemaphoreKHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_external_semaphore" revision="0.9.0" supported="opencl" depends="CL_VERSION_1_2+cl_khr_semaphore" ratified="opencl">
+        <extension name="cl_khr_external_semaphore" revision="1.0.0" supported="opencl" depends="CL_VERSION_1_2+cl_khr_semaphore" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -7054,7 +7054,7 @@ server's OpenCL/api-docs repository.
                 <command name="clGetSemaphoreHandleForTypeKHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_external_semaphore_opaque_fd" revision="0.9.0" supported="opencl" depends="CL_VERSION_1_2+cl_khr_semaphore+cl_khr_external_semaphore" ratified="opencl">
+        <extension name="cl_khr_external_semaphore_opaque_fd" revision="1.0.0" supported="opencl" depends="CL_VERSION_1_2+cl_khr_semaphore+cl_khr_external_semaphore" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -7062,7 +7062,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_SEMAPHORE_HANDLE_OPAQUE_FD_KHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_external_semaphore_sync_fd" revision="0.9.0" supported="opencl" depends="CL_VERSION_1_2+cl_khr_semaphore+cl_khr_external_semaphore" ratified="opencl">
+        <extension name="cl_khr_external_semaphore_sync_fd" revision="1.0.0" supported="opencl" depends="CL_VERSION_1_2+cl_khr_semaphore+cl_khr_external_semaphore" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -7085,7 +7085,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_SEMAPHORE_HANDLE_OPAQUE_WIN32_KMT_KHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_external_memory" revision="0.9.3" supported="opencl" depends="CL_VERSION_3_0" ratified="opencl">
+        <extension name="cl_khr_external_memory" revision="1.0.0" supported="opencl" depends="CL_VERSION_3_0" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -7112,7 +7112,7 @@ server's OpenCL/api-docs repository.
                 <command name="clEnqueueReleaseExternalMemObjectsKHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_external_memory_dma_buf" revision="0.9.3" supported="opencl" depends="CL_VERSION_3_0+cl_khr_external_memory" ratified="opencl">
+        <extension name="cl_khr_external_memory_dma_buf" revision="1.0.0" supported="opencl" depends="CL_VERSION_3_0+cl_khr_external_memory" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -7120,7 +7120,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_EXTERNAL_MEMORY_HANDLE_DMA_BUF_KHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_external_memory_opaque_fd" revision="0.9.3" supported="opencl" depends="CL_VERSION_3_0+cl_khr_external_memory" ratified="opencl">
+        <extension name="cl_khr_external_memory_opaque_fd" revision="1.0.0" supported="opencl" depends="CL_VERSION_3_0+cl_khr_external_memory" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -7128,7 +7128,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_EXTERNAL_MEMORY_HANDLE_OPAQUE_FD_KHR"/>
             </require>
         </extension>
-        <extension name="cl_khr_external_memory_win32" revision="0.9.3" supported="opencl" depends="CL_VERSION_3_0+cl_khr_external_memory" ratified="opencl">
+        <extension name="cl_khr_external_memory_win32" revision="1.0.0" supported="opencl" depends="CL_VERSION_3_0+cl_khr_external_memory" ratified="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -7137,37 +7137,37 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_EXTERNAL_MEMORY_HANDLE_OPAQUE_WIN32_KMT_KHR"/>
             </require>
         </extension>
-        <extension name="cl_intel_sharing_format_query" supported="opencl">
+        <extension name="cl_intel_sharing_format_query" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
         </extension>
-        <extension name="cl_intel_sharing_format_query_gl" supported="opencl" comment="GL API for cl_intel_sharing_format_query">
+        <extension name="cl_intel_sharing_format_query_gl" revision="0.0.0" supported="opencl" comment="GL API for cl_intel_sharing_format_query">
             <require comment="when cl_khr_gl_sharing is supported">
                 <command name="clGetSupportedGLTextureFormatsINTEL"/>
             </require>
         </extension>
-        <extension name="cl_intel_sharing_format_query_dx9" supported="opencl" comment="DX9 API for cl_intel_sharing_format_query">
+        <extension name="cl_intel_sharing_format_query_dx9" revision="0.0.0" supported="opencl" comment="DX9 API for cl_intel_sharing_format_query">
             <require comment="when cl_khr_dx9_media_sharing or cl_intel_dx9_media_sharing is supported">
                 <command name="clGetSupportedDX9MediaSurfaceFormatsINTEL"/>
             </require>
         </extension>
-        <extension name="cl_intel_sharing_format_query_d3d10" supported="opencl" comment="D3D10 API for cl_intel_sharing_format_query">
+        <extension name="cl_intel_sharing_format_query_d3d10" revision="0.0.0" supported="opencl" comment="D3D10 API for cl_intel_sharing_format_query">
             <require comment="when cl_khr_d3d10_sharing is supported">
                 <command name="clGetSupportedD3D10TextureFormatsINTEL"/>
             </require>
         </extension>
-        <extension name="cl_intel_sharing_format_query_d3d11" supported="opencl" comment="D3D11 API for cl_intel_sharing_format_query">
+        <extension name="cl_intel_sharing_format_query_d3d11" revision="0.0.0" supported="opencl" comment="D3D11 API for cl_intel_sharing_format_query">
             <require comment="when cl_khr_d3d11_sharing is supported">
                 <command name="clGetSupportedD3D11TextureFormatsINTEL"/>
             </require>
         </extension>
-        <extension name="cl_intel_sharing_format_query_va_api" supported="opencl" comment="VA_API API for cl_intel_sharing_format_query">
+        <extension name="cl_intel_sharing_format_query_va_api" revision="0.0.0" supported="opencl" comment="VA_API API for cl_intel_sharing_format_query">
             <require comment="when cl_intel_va_api_media_sharing is supported">
                 <command name="clGetSupportedVA_APIMediaSurfaceFormatsINTEL"/>
             </require>
         </extension>
-        <extension name="cl_pocl_content_size" supported="opencl">
+        <extension name="cl_pocl_content_size" revision="0.0.0" supported="opencl">
             <require>
                 <command name="clSetContentSizeBufferPoCL"/>
             </require>
@@ -7246,12 +7246,12 @@ server's OpenCL/api-docs repository.
                 <command name="clCommandSVMMemFillKHR"/>
             </require>
         </extension>
-        <extension name="cl_arm_protected_memory_allocation" supported="opencl">
+        <extension name="cl_arm_protected_memory_allocation" revision="0.0.0" supported="opencl">
             <require>
                 <enum name="CL_MEM_PROTECTED_ALLOC_ARM"/>
             </require>
         </extension>
-        <extension name="cl_ext_float_atomics" supported="opencl">
+        <extension name="cl_ext_float_atomics" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -7272,7 +7272,7 @@ server's OpenCL/api-docs repository.
                 <enum name="CL_DEVICE_HALF_FP_ATOMIC_CAPABILITIES_EXT"/>
             </require>
         </extension>
-        <extension name="cl_intel_program_scope_host_pipe" supported="opencl">
+        <extension name="cl_intel_program_scope_host_pipe" revision="0.0.0" supported="opencl">
             <require>
                 <type name="CL/cl.h"/>
             </require>
@@ -7289,7 +7289,7 @@ server's OpenCL/api-docs repository.
                 <command name="clEnqueueWriteHostPipeINTEL"/>
             </require>
         </extension>
-        <extension name="cl_ext_image_requirements_info" condition="defined(CL_VERSION_3_0)" supported="opencl">
+        <extension name="cl_ext_image_requirements_info" revision="0.0.0" condition="defined(CL_VERSION_3_0)" supported="opencl">
             <require comment="Types">
                 <type name="cl_image_requirements_info_ext"/>
             </require>
@@ -7306,12 +7306,12 @@ server's OpenCL/api-docs repository.
                 <command name="clGetImageRequirementsInfoEXT"/>
             </require>
         </extension>
-        <extension name="cl_intel_queue_no_sync_operations" supported="opencl">
+        <extension name="cl_intel_queue_no_sync_operations" revision="0.0.0" supported="opencl">
             <require comment="cl_command_queue_properties">
                 <enum name="CL_QUEUE_NO_SYNC_OPERATIONS_INTEL"/>
             </require>
         </extension>
-        <extension name="cl_arm_job_slot_selection" supported="opencl">
+        <extension name="cl_arm_job_slot_selection" revision="0.0.0" supported="opencl">
             <require comment="cl_device_info">
                 <enum name="CL_DEVICE_JOB_SLOTS_ARM"/>
             </require>
@@ -7382,12 +7382,12 @@ server's OpenCL/api-docs repository.
                 <command name="clGetMutableCommandInfoKHR"/>
             </require>
         </extension>
-        <extension name="cl_ext_image_from_buffer" condition="defined(CL_VERSION_3_0)" supported="opencl">
+        <extension name="cl_ext_image_from_buffer" revision="0.0.0" condition="defined(CL_VERSION_3_0)" supported="opencl">
             <require comment="cl_image_requirements_info_ext">
                 <enum name="CL_IMAGE_REQUIREMENTS_SLICE_PITCH_ALIGNMENT_EXT"/>
             </require>
         </extension>
-        <extension name="cl_intel_create_mem_object_properties" supported="opencl">
+        <extension name="cl_intel_create_mem_object_properties" revision="0.0.0" supported="opencl">
             <require comment="cl_mem_properties">
                 <enum name="CL_MEM_LOCALLY_UNCACHED_RESOURCE_INTEL"/>
                 <enum name="CL_MEM_DEVICE_ID_INTEL"/>
@@ -7422,41 +7422,41 @@ server's OpenCL/api-docs repository.
                 <command name="clRemapCommandBufferKHR"/>
             </require>
         </extension>
-        <extension name="cl_ext_image_raw10_raw12" supported="opencl">
+        <extension name="cl_ext_image_raw10_raw12" revision="0.0.0" supported="opencl">
             <require comment="cl_channel_type">
                 <enum name="CL_UNSIGNED_INT_RAW10_EXT"/>
                 <enum name="CL_UNSIGNED_INT_RAW12_EXT"/>
             </require>
         </extension>
-        <extension name="cl_khr_3d_image_writes" supported="opencl" promotedto="CL_VERSION_2_0" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_async_work_group_copy_fence" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_byte_addressable_store" supported="opencl" promotedto="CL_VERSION_1_1" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_device_enqueue_local_arg_types" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_expect_assume" supported="opencl" ratified="opencl" comment="OpenCL C only - not exactly an extension, but a compiler directive?"/>
-        <extension name="cl_khr_extended_async_copies" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_extended_bit_ops" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_global_int32_base_atomics" supported="opencl" promotedto="CL_VERSION_1_1" ratified="opencl" comment="OpenCL C only, promotion with name changes"/>
-        <extension name="cl_khr_global_int32_extended_atomics" supported="opencl" promotedto="CL_VERSION_1_1" ratified="opencl" comment="OpenCL C only, promotion with name changes"/>
-        <extension name="cl_khr_local_int32_base_atomics" supported="opencl" promotedto="CL_VERSION_1_1" ratified="opencl" comment="OpenCL C only, promotion with name changes"/>
-        <extension name="cl_khr_local_int32_extended_atomics" supported="opencl" promotedto="CL_VERSION_1_1" ratified="opencl" comment="OpenCL C only, promotion with name changes"/>
-        <extension name="cl_khr_int64_base_atomics" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_int64_extended_atomics" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_mipmap_image_writes" supported="opencl" depends="cl_khr_mipmap_image" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_select_fprounding_mode" supported="opencl" obsoletedby="CL_VERSION_1_1" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_srgb_image_writes" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_subgroup_extended_types" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_subgroup_non_uniform_vote" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_subgroup_ballot" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_subgroup_non_uniform_arithmetic" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_subgroup_shuffle" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_subgroup_shuffle_relative" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_subgroup_clustered_reduce" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_subgroup_rotate" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_work_group_uniform_arithmetic" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
-        <extension name="cl_khr_spirv_no_integer_wrap_decoration" supported="opencl" ratified="opencl" comment="SPIR-V only"/>
-        <extension name="cl_khr_spirv_extended_debug_info" supported="opencl" ratified="opencl" comment="SPIR-V only"/>
-        <extension name="cl_khr_spirv_linkonce_odr" supported="opencl" ratified="opencl" comment="SPIR-V only"/>
-        <extension name="cl_img_cancel_command" supported="opencl">
+        <extension name="cl_khr_3d_image_writes" revision="1.0.0" supported="opencl" promotedto="CL_VERSION_2_0" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_async_work_group_copy_fence" revision="1.0.0" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_byte_addressable_store" revision="1.0.0" supported="opencl" promotedto="CL_VERSION_1_1" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_device_enqueue_local_arg_types" revision="1.0.0" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_expect_assume" revision="1.0.0" supported="opencl" ratified="opencl" comment="OpenCL C only - not exactly an extension, but a compiler directive?"/>
+        <extension name="cl_khr_extended_async_copies" revision="1.0.0" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_extended_bit_ops" revision="1.0.0" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_global_int32_base_atomics" revision="1.0.0" supported="opencl" promotedto="CL_VERSION_1_1" ratified="opencl" comment="OpenCL C only, promotion with name changes"/>
+        <extension name="cl_khr_global_int32_extended_atomics" revision="1.0.0" supported="opencl" promotedto="CL_VERSION_1_1" ratified="opencl" comment="OpenCL C only, promotion with name changes"/>
+        <extension name="cl_khr_local_int32_base_atomics" revision="1.0.0" supported="opencl" promotedto="CL_VERSION_1_1" ratified="opencl" comment="OpenCL C only, promotion with name changes"/>
+        <extension name="cl_khr_local_int32_extended_atomics" revision="1.0.0" supported="opencl" promotedto="CL_VERSION_1_1" ratified="opencl" comment="OpenCL C only, promotion with name changes"/>
+        <extension name="cl_khr_int64_base_atomics" revision="1.0.0" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_int64_extended_atomics" revision="1.0.0" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_mipmap_image_writes" revision="1.0.0" supported="opencl" depends="cl_khr_mipmap_image" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_select_fprounding_mode" revision="1.0.0" supported="opencl" obsoletedby="CL_VERSION_1_1" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_srgb_image_writes" revision="1.0.0" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_subgroup_extended_types" revision="1.0.0" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_subgroup_non_uniform_vote" revision="1.0.0" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_subgroup_ballot" revision="1.0.0" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_subgroup_non_uniform_arithmetic" revision="1.0.0" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_subgroup_shuffle" revision="1.0.0" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_subgroup_shuffle_relative" revision="1.0.0" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_subgroup_clustered_reduce" revision="1.0.0" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_subgroup_rotate" revision="1.0.0" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_work_group_uniform_arithmetic" revision="1.0.0" supported="opencl" ratified="opencl" comment="OpenCL C only"/>
+        <extension name="cl_khr_spirv_no_integer_wrap_decoration" revision="1.0.0" supported="opencl" ratified="opencl" comment="SPIR-V only"/>
+        <extension name="cl_khr_spirv_extended_debug_info" revision="1.0.0" supported="opencl" ratified="opencl" comment="SPIR-V only"/>
+        <extension name="cl_khr_spirv_linkonce_odr" revision="1.0.0" supported="opencl" ratified="opencl" comment="SPIR-V only"/>
+        <extension name="cl_img_cancel_command" revision="0.0.0" supported="opencl">
             <require comment="Error codes">
                 <enum name="CL_CANCELLED_IMG"/>
             </require>
@@ -7464,7 +7464,7 @@ server's OpenCL/api-docs repository.
                 <command name="clCancelCommandsIMG"/>
             </require>
         </extension>
-        <extension name="cl_khr_kernel_clock" supported="opencl" ratified="opencl" provisional="true">
+        <extension name="cl_khr_kernel_clock" revision="0.9.0" supported="opencl" ratified="opencl" provisional="true">
             <require>
                 <type name="CL/cl.h"/>
             </require>
diff --git a/xml/registry.rnc b/xml/registry.rnc
index 210073c2..ff85c0d1 100644
--- a/xml/registry.rnc
+++ b/xml/registry.rnc
@@ -445,7 +445,7 @@ Extensions = element extensions {
 #     exactly match an API being generated (implicit ^$ surrounding).
 #   name - extension name string
 #   number - extension number (positive integer, should be unique)
-#   revision - extension spec revision (text, usually numeric major.minor.patch)
+#   revision - extension spec revision, must be numeric 'major.minor.patch'
 #   sortorder - order relative to other extensions, default 0
 #   protect - C preprocessor symbol to conditionally define the interface
 #   platform - should be one of the platform names defined in the
@@ -479,8 +479,8 @@ Extensions = element extensions {
 #       Not a regular expression.
 Extension = element extension {
     Name ,
+    attribute revision { text },
     attribute number { Integer } ? ,
-    attribute revision { text } ? ,
     attribute sortorder { xsd:integer } ?,
     attribute protect { text } ? ,
     attribute platform { text } ? ,