------- Comment #3 from matz at gcc dot gnu dot org 2008-01-22 18:28 -------
The problem is, that gen_type_die() generates a DIE only for the main variant
of the given type. But lookup_type_die looks in the type itself. In the
example the type in question is "const A", for which no DIE exists already.
So force_type_die() goes into the if(), calls gen_type_die which generated
a DIE for "A" (in fact that already exists, so it just returns). But
a DIE for "const A" still doesn't exist of course. The example can be made to
compile to force such existence, e.g. by adding a member to "A":
struct A {
...
void cmem() const;
};
There are two ways of fixing this:
1) making sure, that "const A" (the tree node) refers to the DIE for "A", i.e.
losing the qualifiers. One could ensure this in either force_type_die
or even gen_type_die by calling equate_type_number_to_die.
2) ensure that force_type_die() really creates a DIE which reflects type
(and not just the main variant).
With the above test one can see, that the intention was, that the AT_import
decl really comes inside the DIE for "const A". So, that speaks for option 2.
This is also the natural choice as a function named "force_type_die" surely
should generate a DIE for that very type and not some other variant of it.
The below patch would implement this.
Index: dwarf2out.c
===================================================================
--- dwarf2out.c (revision 131712)
+++ dwarf2out.c (working copy)
@@ -13736,11 +13736,8 @@ force_type_die (tree type)
else
context_die = comp_unit_die;
- type_die = lookup_type_die (type);
- if (type_die)
- return type_die;
- gen_type_die (type, context_die);
- type_die = lookup_type_die (type);
+ type_die = modified_type_die (type, TYPE_READONLY (type),
+ TYPE_VOLATILE (type), context_die);
gcc_assert (type_die);
}
return type_die;
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34895
