[flang-commits] [flang] [flang] Enumeration Type: (PR 2/5) Name Resolution + Expression + Relational + SELECT CASE (PR #193028)

[via flang-commits]

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@@ -6011,14 +6014,90 @@ bool DeclarationVisitor::Pre(const parser::Enumerator &enumerator) {
   return false;
 }
 
+void DeclarationVisitor::Post(const parser::EnumDef &) {
+  enumerationState_ = EnumeratorState{};
+}
+
+// F2023 R766 EnumerationTypeDef — scope is pushed in Post(EnumerationTypeStmt)
+// and popped in Post(EndEnumerationTypeStmt).
 bool DeclarationVisitor::Pre(const parser::EnumerationTypeDef &x) {
-  Say(std::get<parser::Statement<parser::EnumerationTypeStmt>>(x.t).source,
-      "F2023 ENUMERATION TYPEs are not yet implemented"_err_en_US);
+  BeginAttrs();
+  return true;
+}
+
+// F2023 R767 EnumerationTypeStmt — create the enumeration type symbol
+// in the enclosing scope and push a DerivedType scope for it.
+void DeclarationVisitor::Post(const parser::EnumerationTypeStmt &x) {
+  const auto &name{std::get<parser::Name>(x.t)};
+  Attrs attrs{EndAttrs()};
+  if (const auto &optAccessSpec{
+          std::get<std::optional<parser::AccessSpec>>(x.t)};
+      optAccessSpec) {
+    if (!NonDerivedTypeScope().IsModule()) { // F2023 C7114
+      Say(currStmtSource().value(),
+          "Access specifier on ENUMERATION TYPE may only appear in the specification part of a module"_err_en_US);
+    }
+  }
+  DerivedTypeDetails details;
+  details.set_isEnumerationType(true);
+  auto &symbol{MakeSymbol(name, attrs, std::move(details))};
+  symbol.ReplaceName(name.source);
+  PushScope(Scope::Kind::DerivedType, &symbol);
+  // Add a hidden __ordinal component to hold the 1-based enumerator position.
+  // This is a compiler-created INTEGER(4) component that preserves ordinal
+  // identity through constant folding and enables enumerator comparison.
+  SourceName ordinalName{context().SaveTempName(std::string{"__ordinal"})};
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kwyatt-ext wrote:

Done.

https://github.com/llvm/llvm-project/pull/193028