Return gdbpy_ref<> from gdbpy_registry::lookup

This changes gdbpy_registry::lookup to return a gdbpy_ref<>, using the
type system to convey that a new reference is always returned.

Approved-By: Simon Marchi <simon.marchi@efficios.com>

4 files changed, 21 insertions, 23 deletions

diff --git a/gdb/python/py-symbol.c b/gdb/python/py-symbol.c
index 7b6164fb20d..e8ff2dfe28a 100644
--- a/gdb/python/py-symbol.c
+++ b/gdb/python/py-symbol.c
@@ -339,18 +339,17 @@ set_symbol (symbol_object *obj, struct symbol *symbol)
 gdbpy_ref<>
 symbol_to_symbol_object (struct symbol *sym)
 {
-  symbol_object *sym_obj;
-
   /* Look if there's already a gdb.Symbol object for given SYMBOL
      and if so, return it.  */
+  gdbpy_ref<> result;
   if (sym->is_objfile_owned ())
-    sym_obj = sympy_registry.lookup (sym->objfile (), sym);
+    result = sympy_registry.lookup (sym->objfile (), sym);
   else
-    sym_obj = sympy_registry.lookup (sym->arch (), sym);
-  if (sym_obj != nullptr)
-    return gdbpy_ref<> (sym_obj);
+    result = sympy_registry.lookup (sym->arch (), sym);
+  if (result != nullptr)
+    return result;
 
-  sym_obj = PyObject_New (symbol_object, &symbol_object_type);
+  symbol_object *sym_obj = PyObject_New (symbol_object, &symbol_object_type);
   if (sym_obj)
     set_symbol (sym_obj, sym);
 
diff --git a/gdb/python/py-symtab.c b/gdb/python/py-symtab.c
index ed5abac1372..27d6c4beba9 100644
--- a/gdb/python/py-symtab.c
+++ b/gdb/python/py-symtab.c
@@ -377,10 +377,10 @@ symtab_to_symtab_object (struct symtab *symtab)
      and if so, return it.  */
   if (symtab != nullptr)
     {
-      symtab_obj = stpy_registry.lookup (symtab->compunit ()->objfile (),
-					 symtab);
-      if (symtab_obj != nullptr)
-	return gdbpy_ref<> (symtab_obj);
+      gdbpy_ref<> result
+	= stpy_registry.lookup (symtab->compunit ()->objfile (), symtab);
+      if (result != nullptr)
+	return result;
     }
 
   symtab_obj = PyObject_New (symtab_object, &symtab_object_type);
diff --git a/gdb/python/py-type.c b/gdb/python/py-type.c
index 8f8f6e326a8..b6807801f7e 100644
--- a/gdb/python/py-type.c
+++ b/gdb/python/py-type.c
@@ -1426,8 +1426,6 @@ typy_iterator_dealloc (PyObject *obj)
 gdbpy_ref<>
 type_to_type_object (struct type *type)
 {
-  type_object *type_obj;
-
   try
     {
       /* Try not to let stub types leak out to Python.  */
@@ -1445,18 +1443,20 @@ type_to_type_object (struct type *type)
 
   /* Look if there's already a gdb.Type object for given TYPE
      and if so, return it.  */
+  gdbpy_ref<> result;
   if (type->is_objfile_owned ())
-    type_obj = typy_registry.lookup (type->objfile_owner (), type);
+    result = typy_registry.lookup (type->objfile_owner (), type);
   else
-    type_obj = typy_registry.lookup (type->arch_owner (), type);
+    result = typy_registry.lookup (type->arch_owner (), type);
 
-  if (type_obj == nullptr)
+  if (result == nullptr)
     {
-      type_obj = PyObject_New (type_object, &type_object_type);
-      if (type_obj)
+      type_object *type_obj = PyObject_New (type_object, &type_object_type);
+      if (type_obj != nullptr)
 	set_type (type_obj, type);
+      result = gdbpy_ref<> (type_obj);
     }
-  return gdbpy_ref<> (type_obj);
+  return result;
 }
 
 struct type *
diff --git a/gdb/python/python-internal.h b/gdb/python/python-internal.h
index 1f0964f24d3..fdd353ffbeb 100644
--- a/gdb/python/python-internal.h
+++ b/gdb/python/python-internal.h
@@ -1191,14 +1191,13 @@ public:
   }
 
   /* Lookup pre-existing Python object for given VAL.  Return such object
-     if found, otherwise return NULL.  This method always returns new
-     reference.  */
+     if found, otherwise return NULL.  */
   template <typename O>
-  obj_type *lookup (O *owner, val_type *val) const
+  gdbpy_ref<> lookup (O *owner, val_type *val) const
   {
     obj_type *obj = get_storage (owner)->lookup (val);
     Py_XINCREF (static_cast<PyObject *> (obj));
-    return obj;
+    return gdbpy_ref<> (obj);
   }
 
 private: