This patch is the first part of a correction for issues in the compiler
whereby finalization of a heap-allocated class-wide type may cause an
invalid memory read at runtime when the type in question contains a
component whose type has alignment specified.
Tested on x86_64-pc-linux-gnu, committed on trunk
gcc/ada/
* gcc-interface/decl.c (gnat_to_gnu_entity): Skip normal
processing for Itypes that are E_Class_Wide_Subtype with
Equivalent_Type set.diff --git a/gcc/ada/gcc-interface/decl.c b/gcc/ada/gcc-interface/decl.c
--- a/gcc/ada/gcc-interface/decl.c
+++ b/gcc/ada/gcc-interface/decl.c
@@ -335,11 +335,14 @@ gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr, bool definition)
/* Since a use of an itype is a definition, process it as such if it is in
the main unit, except for E_Access_Subtype because it's actually a use
- of its base type, see below. */
+ of its base type, and for E_Class_Wide_Subtype with an Equivalent_Type
+ because it's actually a use of the latter type. */
if (!definition
&& is_type
&& Is_Itype (gnat_entity)
&& Ekind (gnat_entity) != E_Access_Subtype
+ && !(Ekind (gnat_entity) == E_Class_Wide_Subtype
+ && Present (Equivalent_Type (gnat_entity)))
&& !present_gnu_tree (gnat_entity)
&& In_Extended_Main_Code_Unit (gnat_entity))
{
