[flang] Fix spurious error messages due to INTRINSIC nested in BLOCK (#115889)

When skimmming executable parts to collect names used in procedure
calls, it is important to exclude names that have local declarations in
nested BLOCK constructs. The mechanism for handling these nested
declarations was catching only names whose declarations include an
"entity-decl", and so names appearing in other declaration statements
(like INTRINSIC and EXTERNAL statements) were not hidden from the scan,
leading to absurd error messages when such names turn out to be
procedures in the nested BLOCK construct but to not be procedures
outside it.

This patch fixes the code that detects local declarations in BLOCK for
all of the missed cases that don't use entity-decls; only INTRINSIC and
EXTERNAL could affect the procedures whose names are of interest to the
executable part skimmer, but perhaps future work will want to collect
non-procedures as well, so I plugged all of the holes that I could find.

Fixes https://github.com/llvm/llvm-project/issues/115674.

flang/lib/Semantics/resolve-names.cpp

@@ -4821,10 +4821,13 @@ void DeclarationVisitor::Post(const parser::EntityDecl &x) {
   } else if (attrs.test(Attr::PARAMETER)) { // C882, C883
     Say(name, "Missing initialization for parameter '%s'"_err_en_US);
   }
-  if (auto *scopeSymbol{currScope().symbol()})
-    if (auto *details{scopeSymbol->detailsIf<DerivedTypeDetails>()})
-      if (details->isDECStructure())
+  if (auto *scopeSymbol{currScope().symbol()}) {
+    if (auto *details{scopeSymbol->detailsIf<DerivedTypeDetails>()}) {
+      if (details->isDECStructure()) {
         details->add_component(symbol);
+      }
+    }
+  }
 }
 
 void DeclarationVisitor::Post(const parser::PointerDecl &x) {
@@ -7694,10 +7697,54 @@ public:
     --blockDepth_;
     PopScope();
   }
+  // Note declarations of local names in BLOCK constructs.
+  // Don't have to worry about INTENT(), VALUE, or OPTIONAL
+  // (pertinent only to dummy arguments), ASYNCHRONOUS/VOLATILE,
+  // or accessibility attributes,
   bool Pre(const parser::EntityDecl &x) {
     Hide(std::get<parser::ObjectName>(x.t));
     return true;
   }
+  bool Pre(const parser::ObjectDecl &x) {
+    Hide(std::get<parser::ObjectName>(x.t));
+    return true;
+  }
+  bool Pre(const parser::PointerDecl &x) {
+    Hide(std::get<parser::Name>(x.t));
+    return true;
+  }
+  bool Pre(const parser::BindEntity &x) {
+    Hide(std::get<parser::Name>(x.t));
+    return true;
+  }
+  bool Pre(const parser::ContiguousStmt &x) {
+    for (const parser::Name &name : x.v) {
+      Hide(name);
+    }
+    return true;
+  }
+  bool Pre(const parser::DimensionStmt::Declaration &x) {
+    Hide(std::get<parser::Name>(x.t));
+    return true;
+  }
+  bool Pre(const parser::ExternalStmt &x) {
+    for (const parser::Name &name : x.v) {
+      Hide(name);
+    }
+    return true;
+  }
+  bool Pre(const parser::IntrinsicStmt &x) {
+    for (const parser::Name &name : x.v) {
+      Hide(name);
+    }
+    return true;
+  }
+  bool Pre(const parser::CodimensionStmt &x) {
+    for (const parser::CodimensionDecl &decl : x.v) {
+      Hide(std::get<parser::Name>(decl.t));
+    }
+    return true;
+  }
   void Post(const parser::ImportStmt &x) {
     if (x.kind == common::ImportKind::None ||
         x.kind == common::ImportKind::Only) {

flang/test/Semantics/bug115674.f90

@@ -0,0 +1,9 @@
+!RUN: %flang_fc1 -fsyntax-only %s 2>&1 | FileCheck --allow-empty %s
+!CHECK-NOT: error:
+program main
+  sin = 1
+  block
+    intrinsic sin
+    print *, sin(0.)
+  end block
+end