From e96d9a5b935fc7f5fef9c33e5829ed0a6dfd3178 Mon Sep 17 00:00:00 2001
From: Karol Herbst <kherbst@redhat.com>
Date: Wed, 28 May 2025 14:11:40 +0200
Subject: [PATCH 1/2] Rework anon union usage in cl.h

We already have helper macros in cl_platform.h we can use instead of the
current mess.
---
 CL/cl.h | 41 +++++++++++++----------------------------
 1 file changed, 13 insertions(+), 28 deletions(-)

diff --git a/CL/cl.h b/CL/cl.h
index 792e20cc..d5577201 100644
--- a/CL/cl.h
+++ b/CL/cl.h
@@ -24,6 +24,12 @@
 extern "C" {
 #endif
 
+#if defined(_WIN32) && defined(_MSC_VER) && __CL_HAS_ANON_STRUCT__
+   /* Disable warning C4201: nonstandard extension used : nameless struct/union */
+    #pragma warning( push )
+    #pragma warning( disable : 4201 )
+#endif
+
 /******************************************************************************/
 
 typedef struct _cl_platform_id *    cl_platform_id;
@@ -133,39 +139,14 @@ typedef struct _cl_image_desc {
     size_t                  image_slice_pitch;
     cl_uint                 num_mip_levels;
     cl_uint                 num_samples;
-#ifdef CL_VERSION_2_0
-#if defined(__GNUC__)
-    __extension__                   /* Prevents warnings about anonymous union in -pedantic builds */
-#endif
-#if defined(_MSC_VER) && !defined(__STDC__)
-#pragma warning( push )
-#pragma warning( disable : 4201 )   /* Prevents warning about nameless struct/union in /W4 builds */
-#endif
-#ifdef __clang__
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wc11-extensions" /* Prevents warning about nameless union being C11 extension*/
-#endif
-#if defined(_MSC_VER) && defined(__STDC__)
-    /* Anonymous unions are not supported in /Za builds */
-#else
-    union {
-#endif
+#if defined(CL_VERSION_2_0) && __CL_HAS_ANON_STRUCT__
+    __CL_ANON_STRUCT__ union {
 #endif
       cl_mem                  buffer;
-#ifdef CL_VERSION_2_0
-#if defined(_MSC_VER) && defined(__STDC__)
-    /* Anonymous unions are not supported in /Za builds */
-#else
+#if defined(CL_VERSION_2_0) && __CL_HAS_ANON_STRUCT__
       cl_mem                  mem_object;
     };
 #endif
-#if defined(_MSC_VER) && !defined(__STDC__)
-#pragma warning( pop )
-#endif
-#ifdef __clang__
-#pragma clang diagnostic pop
-#endif
-#endif
 } cl_image_desc;
 
 #endif
@@ -1932,4 +1913,8 @@ clEnqueueTask(cl_command_queue  command_queue,
 }
 #endif
 
+#if defined(_WIN32) && defined(_MSC_VER) && __CL_HAS_ANON_STRUCT__
+    #pragma warning( pop )
+#endif
+
 #endif  /* __OPENCL_CL_H */

From 66265a6fc8565561e841dde4314a809b825ddd50 Mon Sep 17 00:00:00 2001
From: Karol Herbst <kherbst@redhat.com>
Date: Tue, 27 May 2025 20:31:48 +0200
Subject: [PATCH 2/2] Add unions for ICD2 tags in cl_icd_dispatch

I need this, because otherwise rustc doesn't let me use a constant in
place of a function pointer. But I think being more explicit here would
make the code a bit cleaner for loader implementors.
---
 CL/cl_icd.h | 31 +++++++++++++++++++++++++++++--
 1 file changed, 29 insertions(+), 2 deletions(-)

diff --git a/CL/cl_icd.h b/CL/cl_icd.h
index 435ad483..bce60ea2 100644
--- a/CL/cl_icd.h
+++ b/CL/cl_icd.h
@@ -22,6 +22,7 @@
 #include <CL/cl_egl.h>
 #include <CL/cl_ext.h>
 #include <CL/cl_gl.h>
+#include <CL/cl_platform.h>
 
 #if defined(_WIN32)
 #include <CL/cl_d3d11.h>
@@ -29,6 +30,12 @@
 #include <CL/cl_dx9_media_sharing.h>
 #endif
 
+#if defined(_WIN32) && defined(_MSC_VER) && __CL_HAS_ANON_STRUCT__
+   /* Disable warning C4201: nonstandard extension used : nameless struct/union */
+    #pragma warning( push )
+    #pragma warning( disable : 4201 )
+#endif
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -37,7 +44,15 @@ extern "C" {
 
 typedef struct _cl_icd_dispatch {
   /* OpenCL 1.0 */
-  clGetPlatformIDs_t *clGetPlatformIDs;
+#if __CL_HAS_ANON_STRUCT__
+  __CL_ANON_STRUCT__ union {
+#endif
+    clGetPlatformIDs_t *clGetPlatformIDs;
+#if __CL_HAS_ANON_STRUCT__
+    /* Set to CL_ICD2_TAG_KHR for cl_khr_icd 2.0.0 */
+    intptr_t clGetPlatformIDs_icd2_tag;
+  };
+#endif
   clGetPlatformInfo_t *clGetPlatformInfo;
   clGetDeviceIDs_t *clGetDeviceIDs;
   clGetDeviceInfo_t *clGetDeviceInfo;
@@ -68,7 +83,15 @@ typedef struct _cl_icd_dispatch {
   clRetainProgram_t *clRetainProgram;
   clReleaseProgram_t *clReleaseProgram;
   clBuildProgram_t *clBuildProgram;
-  clUnloadCompiler_t *clUnloadCompiler;
+#if __CL_HAS_ANON_STRUCT__
+  __CL_ANON_STRUCT__ union {
+#endif
+    clUnloadCompiler_t *clUnloadCompiler;
+#if __CL_HAS_ANON_STRUCT__
+    /* Set to CL_ICD2_TAG_KHR for cl_khr_icd 2.0.0 */
+    intptr_t clUnloadCompiler_icd2_tag;
+  };
+#endif
   clGetProgramInfo_t *clGetProgramInfo;
   clGetProgramBuildInfo_t *clGetProgramBuildInfo;
   clCreateKernel_t *clCreateKernel;
@@ -312,4 +335,8 @@ typedef struct _cl_icd_dispatch {
 }
 #endif
 
+#if defined(_WIN32) && defined(_MSC_VER) && __CL_HAS_ANON_STRUCT__
+    #pragma warning( pop )
+#endif
+
 #endif /* #ifndef OPENCL_CL_ICD_H */