[flang] Fix bogus errors about CONTIGUOUS attribute

Incorrect error messages were issuing for symbol table entries
with the CONTIGUOUS attribute that didn't deserve them, like
host association symbols.  Put the CONTIGUOUS check into
CheckObjectEntity().

Differential Revision: https://reviews.llvm.org/D150712

Author: klausler

flang/lib/Semantics/check-declarations.cpp

@@ -261,19 +261,6 @@ void CheckHelper::Check(const Symbol &symbol) {
     CheckExplicitSave(symbol);
   }
   const auto *object{symbol.detailsIf<ObjectEntityDetails>()};
-  if (symbol.attrs().test(Attr::CONTIGUOUS)) {
-    if ((!object && !symbol.has<UseDetails>()) ||
-        !((IsPointer(symbol) && symbol.Rank() > 0) || IsAssumedShape(symbol) ||
-            evaluate::IsAssumedRank(symbol))) {
-      if (symbol.owner().IsDerivedType()) { // C752
-        messages_.Say(
-            "A CONTIGUOUS component must be an array with the POINTER attribute"_err_en_US);
-      } else { // C830
-        messages_.Say(
-            "CONTIGUOUS entity must be an array pointer, assumed-shape, or assumed-rank"_err_en_US);
-      }
-    }
-  }
   CheckGlobalName(symbol);
   if (isDone) {
     return; // following checks do not apply
@@ -848,6 +835,17 @@ void CheckHelper::CheckObjectEntity(
         "'%s' is a data object and may not be EXTERNAL"_err_en_US,
         symbol.name());
   }
+  if (symbol.attrs().test(Attr::CONTIGUOUS)) {
+    if ((IsPointer(symbol) && symbol.Rank() > 0) || IsAssumedShape(symbol) ||
+        evaluate::IsAssumedRank(symbol)) {
+    } else if (symbol.owner().IsDerivedType()) { // C752
+      messages_.Say(
+          "A CONTIGUOUS component must be an array with the POINTER attribute"_err_en_US);
+    } else { // C830
+      messages_.Say(
+          "CONTIGUOUS entity must be an array pointer, assumed-shape, or assumed-rank"_err_en_US);
+    }
+  }
 }
 
 void CheckHelper::CheckPointerInitialization(const Symbol &symbol) {

flang/test/Semantics/resolve14.f90

@@ -27,6 +27,12 @@ program p2
   contiguous w
   !ERROR: 'z' is use-associated from module 'm2' and cannot be re-declared
   integer z
+  real, target :: a(10)
+  real, contiguous, pointer :: p(:) => a
   !ERROR: Reference to 'y' is ambiguous
   y = 1
+ contains
+  subroutine inner
+    p(1) = 0. ! ok - check for regression on contiguous host assoc.
+  end subroutine
 end