[clang] [clang] Introduce `SemaOpenMP` (PR #88642)

[Alexey Bataev via cfe-commits]

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@@ -997,6 +987,11 @@ class Sema final : public SemaBase {
     return *OpenACCPtr;
   }
 
+  SemaOpenMP &OpenMP() {
+    assert(OpenMPPtr);
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alexey-bataev wrote:

Add assertion message

https://github.com/llvm/llvm-project/pull/88642