[PATCH] D39505: [OpenMP] Show error if VLAs are not supported

[Jonas Hahnfeld via Phabricator via cfe-commits]

Hahnfeld added inline comments.


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Comment at: include/clang/Basic/TargetInfo.h:944
+  /// \brief Whether target supports variable-length arrays.
+  bool isVLASupported() const { return VLASupported; }
+
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rjmccall wrote:
> The way you've written this makes it sound like "does the target support VLAs?", but the actual semantic checks treat it as "do OpenMP devices on this target support VLAs?"  Maybe there should be a more specific way to query things about OpenMP devices instead of setting a global flag for the target?
Actually, the NVPTX and SPIR targets never support VLAs. So I felt like it would be more correct to make this a global property of the target.

The difference is that the other programming models (OpenCL and CUDA) error out immediatelyand regardless of the target because this limitation is reflected in the standards that disallow VLAs (see SemaType.cpp). For OpenMP we might have target devices that support VLA so we shouldn't error out for those.


https://reviews.llvm.org/D39505