[flang] [llvm] [Flang][OpenMP][Sema] Adding parsing and semantic support for scan directive. (PR #102792)

[Anchu Rajendran S via llvm-commits]

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@@ -198,6 +198,10 @@ class DirectiveStructureChecker : public virtual BaseChecker {
     ClauseMapTy clauseInfo;
     std::list<C> actualClauses;
     std::list<C> crtGroup;
+    std::set<std::string> usedInScanDirective;
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anchuraj wrote:

Hi Sergio, I think it is better to get represented in directive context stack . So once the control goes out of the reduction (directive context), the symbol is no longer marked. Otherwise, some of the semantic checks may be invalid. 

https://github.com/llvm/llvm-project/pull/102792