[flang] Catch non-CONTIGUOUS assumed-rank with ASYNCHRONOUS/VOLATILE …

[klausler]

…forwarded to CONTIGUOUS dummy

No object with the ASYNCHRONOUS or VOLATILE attribute can go through the copy-in/copy-out protocol necessary for argument association with a contiguous dummy array argument. The check for this constraint missed the case of an assumed-rank array without an explicit CONTIGUOUS attribute being forwarded on to a CONTIGUOUS dummy argument.

[llvmbot]

@llvm/pr-subscribers-flang-semantics

Author: Peter Klausler (klausler)

Changes

…forwarded to CONTIGUOUS dummy

No object with the ASYNCHRONOUS or VOLATILE attribute can go through the copy-in/copy-out protocol necessary for argument association with a contiguous dummy array argument. The check for this constraint missed the case of an assumed-rank array without an explicit CONTIGUOUS attribute being forwarded on to a CONTIGUOUS dummy argument.

---

Full diff: https://github.com/llvm/llvm-project/pull/71243.diff

2 Files Affected:

• (modified) flang/lib/Semantics/check-call.cpp (+6-4)
• (modified) flang/test/Semantics/call03.f90 (+4-1)

diff --git a/flang/lib/Semantics/check-call.cpp b/flang/lib/Semantics/check-call.cpp
index bf80dbecab009d9..e095518a60266a7 100644
--- a/flang/lib/Semantics/check-call.cpp
+++ b/flang/lib/Semantics/check-call.cpp
@@ -463,6 +463,7 @@ static void CheckExplicitDataArg(const characteristics::DummyDataObject &dummy,
           : nullptr};
   int actualRank{actualType.Rank()};
   bool actualIsPointer{evaluate::IsObjectPointer(actual)};
+  bool actualIsAssumedRank{evaluate::IsAssumedRank(actual)};
   if (dummy.type.attrs().test(
           characteristics::TypeAndShape::Attr::AssumedShape)) {
     // 15.5.2.4(16)
@@ -478,7 +479,8 @@ static void CheckExplicitDataArg(const characteristics::DummyDataObject &dummy,
     }
   } else if (dummyRank > 0) {
     bool basicError{false};
-    if (actualRank == 0 && !dummyIsAllocatableOrPointer) {
+    if (actualRank == 0 && !actualIsAssumedRank &&
+        !dummyIsAllocatableOrPointer) {
       // Actual is scalar, dummy is an array.  F'2023 15.5.2.5p14
       if (actualIsCoindexed) {
         basicError = true;
@@ -531,7 +533,7 @@ static void CheckExplicitDataArg(const characteristics::DummyDataObject &dummy,
             characteristics::DummyDataObject::Attr::DeducedFromActual)) {
       if (auto dummySize{evaluate::ToInt64(evaluate::Fold(foldingContext,
               evaluate::GetSize(evaluate::Shape{dummy.type.shape()})))}) {
-        if (actualRank == 0) {
+        if (actualRank == 0 && !actualIsAssumedRank) {
           if (evaluate::IsArrayElement(actual)) {
             // Actual argument is a scalar array element
             evaluate::DesignatorFolder folder{
@@ -568,7 +570,7 @@ static void CheckExplicitDataArg(const characteristics::DummyDataObject &dummy,
               }
             }
           }
-        } else { // actualRank > 0
+        } else { // actualRank > 0 || actualIsAssumedRank
           if (auto actualSize{evaluate::ToInt64(evaluate::Fold(foldingContext,
                   evaluate::GetSize(evaluate::Shape(actualType.shape()))))};
               actualSize && *actualSize < *dummySize) {
@@ -644,7 +646,7 @@ static void CheckExplicitDataArg(const characteristics::DummyDataObject &dummy,
           "Coindexed ASYNCHRONOUS or VOLATILE actual argument may not be associated with %s with ASYNCHRONOUS or VOLATILE attributes unless VALUE"_err_en_US,
           dummyName);
     }
-    if (actualRank > 0 && !actualIsContiguous) {
+    if ((actualRank > 0 || actualIsAssumedRank) && !actualIsContiguous) {
       if (dummyIsContiguous ||
           !(dummyIsAssumedShape || dummyIsAssumedRank ||
               (actualIsPointer && dummyIsPointer))) { // C1539 & C1540
diff --git a/flang/test/Semantics/call03.f90 b/flang/test/Semantics/call03.f90
index c31f2cc3eb8db79..2aca8de93acb05f 100644
--- a/flang/test/Semantics/call03.f90
+++ b/flang/test/Semantics/call03.f90
@@ -345,11 +345,12 @@ subroutine test14(a,b,c,d) ! C1538
     call volatile(d[1])
   end subroutine
 
-  subroutine test15() ! C1539
+  subroutine test15(assumedrank) ! C1539
     real, pointer :: a(:)
     real, asynchronous :: b(10)
     real, volatile :: c(10)
     real, asynchronous, volatile :: d(10)
+    real, asynchronous, volatile :: assumedrank(..)
     call assumedsize(a(::2)) ! ok
     call contiguous(a(::2)) ! ok
     call valueassumedsize(a(::2)) ! ok
@@ -368,6 +369,8 @@ subroutine test15() ! C1539
     call volatileassumedsize(d(::2))
     !ERROR: ASYNCHRONOUS or VOLATILE actual argument that is not simply contiguous may not be associated with a contiguous dummy argument 'x='
     call volatilecontiguous(d(::2))
+    !ERROR: ASYNCHRONOUS or VOLATILE actual argument that is not simply contiguous may not be associated with a contiguous dummy argument 'x='
+    call volatilecontiguous(assumedrank)
   end subroutine
 
   subroutine test16() ! C1540

[clementval]

LGTM