[clang] [flang] [clang][OpenMP] Diagnose invalid allocator in `#pragma omp allocate`; avoid null deref (PR #158146)

[Shafik Yaghmour via cfe-commits]

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@@ -3408,8 +3418,7 @@ applyOMPAllocateAttribute(Sema &S, VarDecl *VD,
       (Alignment->isTypeDependent() || Alignment->isValueDependent() ||
        Alignment->isInstantiationDependent() ||
        Alignment->containsUnexpandedParameterPack()))
-    // Apply later when we have a usable value.
-    return;
+    return; // apply later
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shafik wrote:

The old comment seems more helpful, please remove this change.

https://github.com/llvm/llvm-project/pull/158146