[flang] Fix bogus error on statement function

[klausler]

When a statement function in a nested scope has a name that clashes with a name that exists in the host scope, the compiler can handle it correctly (with a portability warning)... unless the host scope acquired the name via USE association. Fix.

Fixes #88678.

[llvmbot]

@llvm/pr-subscribers-flang-semantics

Author: Peter Klausler (klausler)

Changes

When a statement function in a nested scope has a name that clashes with a name that exists in the host scope, the compiler can handle it correctly (with a portability warning)... unless the host scope acquired the name via USE association. Fix.

Fixes #88678.

---

Full diff: https://github.com/llvm/llvm-project/pull/89402.diff

2 Files Affected:

• (modified) flang/lib/Semantics/resolve-names.cpp (+1-1)
• (modified) flang/test/Semantics/stmt-func02.f90 (+13-2)

diff --git a/flang/lib/Semantics/resolve-names.cpp b/flang/lib/Semantics/resolve-names.cpp
index f0198cb792280a..d0b2deccc7f179 100644
--- a/flang/lib/Semantics/resolve-names.cpp
+++ b/flang/lib/Semantics/resolve-names.cpp
@@ -3650,7 +3650,7 @@ bool SubprogramVisitor::HandleStmtFunction(const parser::StmtFunctionStmt &x) {
       misparsedStmtFuncFound_ = true;
       return false;
     }
-    if (DoesScopeContain(&ultimate.owner(), currScope())) {
+    if (IsHostAssociated(*symbol, currScope())) {
       if (context().ShouldWarn(
               common::LanguageFeature::StatementFunctionExtensions)) {
         Say(name,
diff --git a/flang/test/Semantics/stmt-func02.f90 b/flang/test/Semantics/stmt-func02.f90
index 0f4e8c034f659a..bfed280ded58d1 100644
--- a/flang/test/Semantics/stmt-func02.f90
+++ b/flang/test/Semantics/stmt-func02.f90
@@ -1,5 +1,12 @@
 ! RUN: %python %S/test_errors.py %s %flang_fc1 -pedantic
-module m
+module m1
+ contains
+  real function rf2(x)
+    rf2 = x
+  end
+end
+module m2
+  use m1
   real, target :: x = 1.
  contains
   function rpf(x)
@@ -18,7 +25,11 @@ subroutine test1
   end
   subroutine test2
     !PORTABILITY: Name 'rf' from host scope should have a type declaration before its local statement function definition
-    rf(x) = 3.
+    rf(x) = 1.
+  end
+  subroutine test2b
+    !PORTABILITY: Name 'rf2' from host scope should have a type declaration before its local statement function definition
+    rf2(x) = 1.
   end
   subroutine test3
     external sf