[flang] [llvm] [flang][OpenMP] Parsing support for iterator modifiers in FROM and TO (PR #114593)

[Krzysztof Parzyszek via llvm-commits]

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@@ -1647,24 +1700,29 @@ void OmpStructureChecker::CheckOrderedDependClause(
 }
 
 void OmpStructureChecker::CheckTargetUpdate() {
-  const parser::OmpClause *toClause = FindClause(llvm::omp::Clause::OMPC_to);
-  const parser::OmpClause *fromClause =
-      FindClause(llvm::omp::Clause::OMPC_from);
-  if (!toClause && !fromClause) {
+  const parser::OmpClause *toWrapper{FindClause(llvm::omp::Clause::OMPC_to)};
+  const parser::OmpClause *fromWrapper{
+      FindClause(llvm::omp::Clause::OMPC_from)};
+  if (!toWrapper && !fromWrapper) {
     context_.Say(GetContext().directiveSource,
-        "At least one motion-clause (TO/FROM) must be specified on TARGET UPDATE construct."_err_en_US);
+        "At least one motion-clause (TO/FROM) must be specified on "
+        "TARGET UPDATE construct."_err_en_US);
   }
-  if (toClause && fromClause) {
+  if (toWrapper && fromWrapper) {
     SymbolSourceMap toSymbols, fromSymbols;
+    auto &fromClause{std::get<parser::OmpClause::From>(fromWrapper->u).v};
+    auto &toClause{std::get<parser::OmpClause::To>(toWrapper->u).v};
     GetSymbolsInObjectList(
-        std::get<parser::OmpClause::To>(toClause->u).v, toSymbols);
+        std::get<parser::OmpObjectList>(fromClause.t), fromSymbols);
     GetSymbolsInObjectList(
-        std::get<parser::OmpClause::From>(fromClause->u).v, fromSymbols);
+        std::get<parser::OmpObjectList>(toClause.t), toSymbols);
+
     for (auto &[symbol, source] : toSymbols) {
-      auto fromSymbol = fromSymbols.find(symbol);
+      auto fromSymbol{fromSymbols.find(symbol)};
       if (fromSymbol != fromSymbols.end()) {
         context_.Say(source,
-            "A list item ('%s') can only appear in a TO or FROM clause, but not in both."_err_en_US,
+            "A list item ('%s') can only appear in a TO or FROM clause, "
+            "but not in both."_err_en_US,
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kparzysz wrote:

Undone.

https://github.com/llvm/llvm-project/pull/114593