Hi!
The following two functions assume that all types (in the latter case only
the TYPE_MAIN_VARIANT of it) have non-NULL TYPE_CANONICAL. That is
generally not something the FEs guarantee, if TYPE_CANONICAL is NULL, that
is TYPE_STRUCTURAL_EQUALITY_P and generally the middle-end either punts on
those, or does use more careful type comparison etc. In the testcase
we have a FUNCTION_TYPE for which TYPE_STRUCTURAL_EQUALITY_P is true and
the C++ FE sets template types where any of the template parameters requires
structural equality also to require structural equality.
In the following functions, we already have a type (TYPE_MAIN_VARIANT),
using its TYPE_CANONICAL instead when it is NULL means a certain ICE, but I
don't see why we couldn't just use those types.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk and
later for 9.2?
2019-05-03 Jakub Jelinek <ja...@redhat.com>
PR tree-optimization/90303
* ipa-devirt.c (obj_type_ref_class, get_odr_type): Don't use
TYPE_CANONICAL for TYPE_STRUCTURAL_EQUALITY_P types in !in_lto_p mode.
* g++.target/i386/pr90303.C: New test.
--- gcc/ipa-devirt.c.jj 2019-04-15 19:45:28.796340266 +0200
+++ gcc/ipa-devirt.c 2019-05-02 10:46:03.077896176 +0200
@@ -2020,7 +2020,7 @@ obj_type_ref_class (const_tree ref)
ref = TREE_VALUE (TYPE_ARG_TYPES (ref));
gcc_checking_assert (TREE_CODE (ref) == POINTER_TYPE);
tree ret = TREE_TYPE (ref);
- if (!in_lto_p)
+ if (!in_lto_p && !TYPE_STRUCTURAL_EQUALITY_P (ret))
ret = TYPE_CANONICAL (ret);
else
ret = get_odr_type (ret)->type;
@@ -2042,7 +2042,7 @@ get_odr_type (tree type, bool insert)
int base_id = -1;
type = TYPE_MAIN_VARIANT (type);
- if (!in_lto_p)
+ if (!in_lto_p && !TYPE_STRUCTURAL_EQUALITY_P (type))
type = TYPE_CANONICAL (type);
gcc_checking_assert (can_be_name_hashed_p (type)
--- gcc/testsuite/g++.target/i386/pr90303.C.jj 2019-05-02 10:51:42.208456515
+0200
+++ gcc/testsuite/g++.target/i386/pr90303.C 2019-05-02 10:52:15.300925960
+0200
@@ -0,0 +1,8 @@
+// PR tree-optimization/90303
+// { dg-do compile { target ia32 } }
+// { dg-additional-options "-O2" }
+
+struct A { virtual void foo (); };
+template <class> class B : A {};
+typedef void (__attribute__((fastcall)) F) ();
+B<F> e;
Jakub
