From 9a798383691c4e5d6ce38dbff91897dccaa339da Mon Sep 17 00:00:00 2001
From: Matthias Koefferlein <matthias@klayout.de>
Date: Sat, 20 Jul 2024 18:58:29 +0200
Subject: [PATCH] Bugfix for issue-1793: using the heap to properly store the
 default values

---
 src/gsi/gsi/gsiExpression.cc | 8 ++++----
 src/pya/pya/pyaCallables.cc  | 8 ++++----
 src/rba/rba/rba.cc           | 8 ++++----
 3 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/src/gsi/gsi/gsiExpression.cc b/src/gsi/gsi/gsiExpression.cc
index 3d77ddada..46ca33374 100644
--- a/src/gsi/gsi/gsiExpression.cc
+++ b/src/gsi/gsi/gsiExpression.cc
@@ -1036,10 +1036,10 @@ VariantUserClassImpl::execute_gsi (const tl::ExpressionParserContext & /*context
               //  leave it to the consumer to establish the default values (that is faster)
               break;
             }
-            const tl::Variant &def_value = a->spec ()->default_value ();
-            //  NOTE: this const_cast means we need to take care that we do not use default values on "out" parameters.
-            //  Otherwise there is a chance we will modify the default value.
-            gsi::push_arg (arglist, *a, const_cast<tl::Variant &> (def_value), &heap);
+            //  Note: we will use the default value variant for longer, so push it to the heap (#1793)
+            tl::Variant *def_value = new tl::Variant (a->spec ()->default_value ());
+            heap.push (def_value);
+            gsi::push_arg (arglist, *a, *def_value, &heap);
           } else {
             throw tl::Exception (tl::to_string ("No argument provided (positional or keyword) and no default value available"));
           }
diff --git a/src/pya/pya/pyaCallables.cc b/src/pya/pya/pyaCallables.cc
index 05b463f40..5422c9968 100644
--- a/src/pya/pya/pyaCallables.cc
+++ b/src/pya/pya/pyaCallables.cc
@@ -764,10 +764,10 @@ push_args (gsi::SerialArgs &arglist, const gsi::MethodBase *meth, PyObject *args
             //  leave it to the consumer to establish the default values (that is faster)
             break;
           }
-          const tl::Variant &def_value = a->spec ()->default_value ();
-          //  NOTE: this const_cast means we need to take care that we do not use default values on "out" parameters.
-          //  Otherwise there is a chance we will modify the default value.
-          gsi::push_arg (arglist, *a, const_cast<tl::Variant &> (def_value), &heap);
+          //  Note: we will use the default value variant for longer, so push it to the heap (#1793)
+          tl::Variant *def_value = new tl::Variant (a->spec ()->default_value ());
+          heap.push (def_value);
+          gsi::push_arg (arglist, *a, *def_value, &heap);
         } else {
           throw tl::Exception (tl::to_string (tr ("No argument provided (positional or keyword) and no default value available")));
         }
diff --git a/src/rba/rba/rba.cc b/src/rba/rba/rba.cc
index e51abfeb4..21743409b 100644
--- a/src/rba/rba/rba.cc
+++ b/src/rba/rba/rba.cc
@@ -1125,10 +1125,10 @@ push_args (gsi::SerialArgs &arglist, const gsi::MethodBase *meth, VALUE *argv, i
             //  leave it to the consumer to establish the default values (that is faster)
             break;
           }
-          const tl::Variant &def_value = a->spec ()->default_value ();
-          //  NOTE: this const_cast means we need to take care that we do not use default values on "out" parameters.
-          //  Otherwise there is a chance we will modify the default value.
-          gsi::push_arg (arglist, *a, const_cast<tl::Variant &> (def_value), &heap);
+          //  Note: we will use the default value variant for longer, so push it to the heap (#1793)
+          tl::Variant *def_value = new tl::Variant (a->spec ()->default_value ());
+          heap.push (def_value);
+          gsi::push_arg (arglist, *a, *def_value, &heap);
         } else {
           throw tl::Exception (tl::to_string (tr ("No argument provided (positional or keyword) and no default value available")));
         }