diff --git a/flang/lib/Semantics/check-return.cpp b/flang/lib/Semantics/check-return.cpp
--- a/flang/lib/Semantics/check-return.cpp
+++ b/flang/lib/Semantics/check-return.cpp
@@ -36,7 +36,8 @@
             IsFunction(*subprogramScope->GetSymbol()))) {
       context_.Say(
           "RETURN with expression is only allowed in SUBROUTINE subprogram"_err_en_US);
-    } else if (context_.ShouldWarn(common::LanguageFeature::ProgramReturn)) {
+    } else if (subprogramScope->kind() == Scope::Kind::MainProgram &&
+        context_.ShouldWarn(common::LanguageFeature::ProgramReturn)) {
       context_.Say("RETURN should not appear in a main program"_port_en_US);
     }
   }
diff --git a/flang/test/Semantics/altreturn02.f90 b/flang/test/Semantics/altreturn02.f90
--- a/flang/test/Semantics/altreturn02.f90
+++ b/flang/test/Semantics/altreturn02.f90
@@ -1,4 +1,4 @@
-! RUN: %python %S/test_errors.py %s %flang_fc1
+! RUN: %flang_fc1 -fsyntax-only -pedantic %s  2>&1 | FileCheck %s --allow-empty
 ! Check subroutine with alt return
 
        SUBROUTINE TEST (N, *, *)
@@ -6,3 +6,5 @@
        IF ( N .EQ. 1 ) RETURN 1
        RETURN 2
        END
+! CHECK-NOT: error:
+! CHECK-NOT: portability:
diff --git a/flang/test/Semantics/altreturn07.f90 b/flang/test/Semantics/altreturn07.f90
new file mode 100644
--- /dev/null
+++ b/flang/test/Semantics/altreturn07.f90
@@ -0,0 +1,6 @@
+! RUN: %flang_fc1 -fsyntax-only -pedantic %s  2>&1 | FileCheck %s
+! Test extension: RETURN from main program
+
+return
+! CHECK: portability: RETURN should not appear in a main program
+end