[flang][NFC] Verify C781 from - Clause 7 constraint checks for f18.

Reviewed By: PeteSteinfeld

Differential Revision: https://reviews.llvm.org/D84503

flang/lib/Semantics/resolve-names.cpp

@@ -1547,7 +1547,7 @@ bool AttrsVisitor::IsConflictingAttr(Attr attrName) {
   return HaveAttrConflict(attrName, Attr::INTENT_IN, Attr::INTENT_INOUT) ||
       HaveAttrConflict(attrName, Attr::INTENT_IN, Attr::INTENT_OUT) ||
       HaveAttrConflict(attrName, Attr::INTENT_INOUT, Attr::INTENT_OUT) ||
-      HaveAttrConflict(attrName, Attr::PASS, Attr::NOPASS) ||
+      HaveAttrConflict(attrName, Attr::PASS, Attr::NOPASS) || // C781
       HaveAttrConflict(attrName, Attr::PURE, Attr::IMPURE) ||
       HaveAttrConflict(attrName, Attr::PUBLIC, Attr::PRIVATE) ||
       HaveAttrConflict(attrName, Attr::RECURSIVE, Attr::NON_RECURSIVE);

flang/test/Semantics/bindings01.f90

@@ -1,6 +1,6 @@
 ! RUN: %S/test_errors.sh %s %t %f18
 ! Confirm enforcement of constraints and restrictions in 7.5.7.3
-! and C733, C734 and C779, C780, C781, C782, C783, C784, and C785.
+! and C733, C734 and C779, C780, C782, C783, C784, and C785.
 
 module m
   !ERROR: An ABSTRACT derived type must be extensible

flang/test/Semantics/resolve80.f90

@@ -26,7 +26,7 @@ module m
     !WARNING: Attribute 'PASS' cannot be used more than once
     procedure(subPass), pass, deferred, pass :: passBinding
     !ERROR: Attributes 'PASS' and 'NOPASS' conflict with each other
-    procedure(subPassNopass), pass, deferred, nopass :: passNopassBinding
+    procedure(subPassNopass), pass, deferred, nopass :: passNopassBinding  ! C781
   end type boundProcType
 
 contains