[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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@@ -3430,9 +3439,6 @@ SemaOpenMP::DeclGroupPtrTy SemaOpenMP::ActOnOpenMPAllocateDirective(
   Expr *Allocator = nullptr;
   if (Clauses.empty()) {
     // OpenMP 5.0, 2.11.3 allocate Directive, Restrictions.
-    // allocate directives that appear in a target region must specify an
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shafik wrote:

Why did you remove these comments?

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