[flang-commits] [flang] [flang] Handle USE-associated symbols in module procedure interface b… (PR #93616)

[Peter Klausler via flang-commits]

https://github.com/klausler created https://github.com/llvm/llvm-project/pull/93616

…lock specification expressions

A subroutine or function interface block is of course allowed to USE-associate symbols into its scope and use them for specification expressions.  This usage works, but crashes the module file output generator.  Fix.

Fixes https://github.com/llvm/llvm-project/issues/93413.

>From f53c4b6b3ab41b238c75fd1e04bf4bab906818bb Mon Sep 17 00:00:00 2001
From: Peter Klausler <pklausler at nvidia.com>
Date: Tue, 28 May 2024 14:52:50 -0700
Subject: [PATCH] [flang] Handle USE-associated symbols in module procedure
 interface block specification expressions

A subroutine or function interface block is of course allowed to
USE-associate symbols into its scope and use them for specification
expressions.  This usage works, but crashes the module file output
generator.  Fix.

Fixes https://github.com/llvm/llvm-project/issues/93413.
---
 flang/lib/Semantics/resolve-names-utils.cpp | 12 ++++++-----
 flang/test/Semantics/resolve118.f90         | 23 +++++++++++++++++++++
 2 files changed, 30 insertions(+), 5 deletions(-)

diff --git a/flang/lib/Semantics/resolve-names-utils.cpp b/flang/lib/Semantics/resolve-names-utils.cpp
index e27a54361749f..39392257938d6 100644
--- a/flang/lib/Semantics/resolve-names-utils.cpp
+++ b/flang/lib/Semantics/resolve-names-utils.cpp
@@ -710,13 +710,15 @@ class SymbolMapper : public evaluate::AnyTraverse<SymbolMapper, bool> {
   SymbolMapper(Scope &scope, SymbolAndTypeMappings &map)
       : Base{*this}, scope_{scope}, map_{map} {}
   using Base::operator();
-  bool operator()(const SymbolRef &ref) const {
+  bool operator()(const SymbolRef &ref) {
     if (const Symbol *mapped{MapSymbol(*ref)}) {
       const_cast<SymbolRef &>(ref) = *mapped;
+    } else if (ref->has<UseDetails>()) {
+      CopySymbol(&*ref);
     }
     return false;
   }
-  bool operator()(const Symbol &x) const {
+  bool operator()(const Symbol &x) {
     if (MapSymbol(x)) {
       DIE("SymbolMapper hit symbol outside SymbolRef");
     }
@@ -726,9 +728,9 @@ class SymbolMapper : public evaluate::AnyTraverse<SymbolMapper, bool> {
   Symbol *CopySymbol(const Symbol *);
 
 private:
-  void MapParamValue(ParamValue &param) const { (*this)(param.GetExplicit()); }
-  void MapBound(Bound &bound) const { (*this)(bound.GetExplicit()); }
-  void MapShapeSpec(ShapeSpec &spec) const {
+  void MapParamValue(ParamValue &param) { (*this)(param.GetExplicit()); }
+  void MapBound(Bound &bound) { (*this)(bound.GetExplicit()); }
+  void MapShapeSpec(ShapeSpec &spec) {
     MapBound(spec.lbound());
     MapBound(spec.ubound());
   }
diff --git a/flang/test/Semantics/resolve118.f90 b/flang/test/Semantics/resolve118.f90
index 11fa18255f045..024b67b5a471b 100644
--- a/flang/test/Semantics/resolve118.f90
+++ b/flang/test/Semantics/resolve118.f90
@@ -57,3 +57,26 @@ subroutine s4(x)
   subroutine t
   end
 end module
+
+module m6a
+  integer :: i = 7
+end module
+
+module m6b
+  interface
+    module subroutine sub(arg)
+      interface
+        integer function arg(x)
+          use m6a, only: i
+          real :: x(i) ! ok
+        end
+      end interface
+    end
+  end interface
+end module
+
+submodule (m6b) m6bs1
+  contains
+    module procedure sub
+    end
+end submodule