[flang] Address comments; allow "real,parameter::x=tiny(x)"

Original-commit: flang-compiler/f18@e865358871
Reviewed-on: https://github.com/flang-compiler/f18/pull/602

flang/lib/evaluate/fold.cc

@@ -445,14 +445,7 @@ Expr<Type<TypeCategory::Integer, KIND>> FoldIntrinsicFunction(
           return j.value;
         }));
   } else if (name == "bit_size") {
-    if (auto *sx{UnwrapExpr<Expr<SomeInteger>>(args[0])}) {
-      return std::visit(
-          [](const auto &x) {
-            using TR = typename std::decay_t<decltype(x)>::Result;
-            return Expr<T>{Scalar<TR>::bits};
-          },
-          sx->u);
-    }
+    return Expr<T>{Scalar<T>::bits};
   } else if (name == "dim") {
     return FoldElementalIntrinsic<T, T, T>(
         context, std::move(funcRef), &Scalar<T>::DIM);

flang/lib/evaluate/intrinsics.cc

@@ -296,7 +296,7 @@ static const IntrinsicInterface genericIntrinsicFunction[]{
         {{"i", AnyInt, Rank::elementalOrBOZ},
             {"j", AnyInt, Rank::elementalOrBOZ}},
         DefaultLogical},
-    {"bit_size", {{"i", AnyInt, Rank::anyOrAssumedRank}}, DefaultInt,
+    {"bit_size", {{"i", SameInt, Rank::anyOrAssumedRank}}, SameInt,
         Rank::scalar},
     {"ble",
         {{"i", AnyInt, Rank::elementalOrBOZ},

flang/lib/evaluate/shape.h

@@ -56,7 +56,8 @@ std::optional<ConstantSubscripts> AsConstantExtents(const Shape &);
 
 inline int GetRank(const Shape &s) { return static_cast<int>(s.size()); }
 
-// The dimension here is zero-based, unlike DIM= arguments to many intrinsics.
+// The dimension argument to these inquiries is zero-based,
+// unlike the DIM= arguments to many intrinsics.
 MaybeExtentExpr GetLowerBound(
     FoldingContext &, const NamedEntity &, int dimension);
 Shape GetLowerBounds(FoldingContext &, const NamedEntity &);

flang/lib/semantics/resolve-names.cc

@@ -658,6 +658,7 @@ public:
   using ScopeHandler::Post;
   using ScopeHandler::Pre;
 
+  bool Pre(const parser::Initialization &);
   void Post(const parser::EntityDecl &);
   void Post(const parser::ObjectDecl &);
   void Post(const parser::PointerDecl &);
@@ -2636,6 +2637,13 @@ void DeclarationVisitor::Post(const parser::CodimensionDecl &x) {
   DeclareObjectEntity(name, Attrs{});
 }
 
+bool DeclarationVisitor::Pre(const parser::Initialization &) {
+  // Defer inspection of initializers to Initialization() so that the
+  // symbol being initialized will be available within the initialization
+  // expression.
+  return false;
+}
+
 void DeclarationVisitor::Post(const parser::EntityDecl &x) {
   // TODO: may be under StructureStmt
   const auto &name{std::get<parser::ObjectName>(x.t)};
@@ -2677,8 +2685,8 @@ bool DeclarationVisitor::Pre(const parser::NamedConstantDef &x) {
     return false;
   }
   const auto &expr{std::get<parser::ConstantExpr>(x.t)};
-  Walk(expr);
   ApplyImplicitRules(symbol);
+  Walk(expr);
   if (auto converted{
           EvaluateConvertedExpr(symbol, expr, expr.thing.value().source)}) {
     symbol.get<ObjectEntityDetails>().set_init(std::move(*converted));
@@ -4773,6 +4781,10 @@ void DeclarationVisitor::Initialization(const parser::Name &name,
   if (name.symbol == nullptr) {
     return;
   }
+  // Traversal of the initializer was deferred to here so that the
+  // symbol being declared can be available for e.g.
+  //   real, parameter :: x = tiny(x)
+  Walk(init.u);
   Symbol &ultimate{name.symbol->GetUltimate()};
   if (auto *details{ultimate.detailsIf<ObjectEntityDetails>()}) {
     // TODO: check C762 - all bounds and type parameters of component