[clang] [OpenMP] Basic BumpAllocator for (AMD)GPUs (PR #69806)

[Joseph Huber via cfe-commits]

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@@ -15,9 +15,19 @@
 #endif
 
 #ifdef __cplusplus
+#include <cstddef>
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jhuber6 wrote:

I'm unsure if there's ever a reason to include the C++ wrappers in a freestanding environment. Without C++, these go straight to the `clang` resource directly. With the C++ versions they go through the system which hopefully ends up at the resource directory intact.

https://github.com/llvm/llvm-project/pull/69806