[flang] Allow non-definable actual arguments to volatile/asynchronous dummy arguments

[klausler]

Summary

Semantic checking for calls was requiring an actual argument that corresponds
to an ASYNCHRONOUS or VOLATILE dummy argument to be definable, but this is not
a constraint or requirement in the standard and doesn't even make sense
as a warning; these two attributes are "scopable" in the context of BLOCK
constructs. Remove the checks and adjust the tests.

flang/lib/Semantics/check-call.cpp

static void CheckExplicitDataArg(const characteristics::DummyDataObject &dummy,
   }
 
   // Definability
   const char *reason{nullptr};
   if (dummy.intent == common::Intent::Out) {
     reason = "INTENT(OUT)";
   } else if (dummy.intent == common::Intent::InOut) {
     reason = "INTENT(IN OUT)";
-  } else if (dummyIsAsynchronous) {
-    reason = "ASYNCHRONOUS";
-  } else if (dummyIsVolatile) {
-    reason = "VOLATILE";
   }
   if (reason && scope) {
     bool vectorSubscriptIsOk{isElemental || dummyIsValue}; // 15.5.2.4(21)
     if (auto why{WhyNotModifiable(
             messages.at(), actual, *scope, vectorSubscriptIsOk)}) {
       if (auto *msg{messages.Say(
-              "Actual argument associated with %s %s must be definable"_err_en_US, // C1158
+              "Actual argument associated with %s %s must be definable"_err_en_US,
               reason, dummyName)}) {
         msg->Attach(*why);
       }
     }
   }
 
   // Cases when temporaries might be needed but must not be permitted.
   bool actualIsContiguous{IsSimplyContiguous(actual, context)};

flang/test/Semantics/call03.f90

contains
   subroutine test12 ! 15.5.2.4(21)
     real :: a(1)
     integer :: j(1)
     j(1) = 1
     !ERROR: Actual argument associated with INTENT(OUT) dummy argument 'x=' must be definable
     call intentout_arr(a(j))
     !ERROR: Actual argument associated with INTENT(IN OUT) dummy argument 'x=' must be definable
     call intentinout_arr(a(j))
-    !ERROR: Actual argument associated with ASYNCHRONOUS dummy argument 'x=' must be definable
-    call asynchronous_arr(a(j))
-    !ERROR: Actual argument associated with VOLATILE dummy argument 'x=' must be definable
-    call volatile_arr(a(j))
+    call asynchronous_arr(a(j)) ! ok
+    call volatile_arr(a(j)) ! ok
   end subroutine
 
   subroutine coarr(x)
     type(ultimateCoarray):: x
   end subroutine
   subroutine volcoarr(x)
     type(ultimateCoarray), volatile :: x
   end subroutine