https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104583
Marek Polacek <mpolacek at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |mpolacek at gcc dot gnu.org
--- Comment #3 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
The attached 93280 test no longer ICEs but looks like it was never added to the
testsuite. The 104583 test, modified so that it closely resembles 93280, still
ICEs.
The problem is that in 104583 we have a value-init from {}, so this code in
convert_like_internal
7960 /* If we're initializing from {}, it's value-initialization. */
7961 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
7962 && CONSTRUCTOR_NELTS (expr) == 0
7963 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype)
7964 && !processing_template_decl)
7965 {
7966 bool direct = CONSTRUCTOR_IS_DIRECT_INIT (expr);
...
7974 TARGET_EXPR_DIRECT_INIT_P (expr) = direct;
sets TARGET_EXPR_DIRECT_INIT_P (line #1 in 104583). This does not happen in
93280.
When gimplifying, the #2 line, we have
d = {.a=TARGET_EXPR <D.2474, <<< Unknown tree: aggr_init_expr
4
__ct_comp
D.2474
(struct A *) <<< Unknown tree: void_cst >>> >>>>}
where the TARGET_EXPR is the one with TARGET_EXPR_DIRECT_INIT_P set. In
gimplify_init_ctor_preeval we do
4724 FOR_EACH_VEC_SAFE_ELT (v, ix, ce)
4725 gimplify_init_ctor_preeval (&ce->value, pre_p, post_p, data);
so we gimplify the TARGET_EXPR, crashing at
744 case TARGET_EXPR:
745 /* A TARGET_EXPR that expresses direct-initialization should have
been
746 elided by cp_gimplify_init_expr. */
747 gcc_checking_assert (!TARGET_EXPR_DIRECT_INIT_P (*expr_p));
but there is no INIT_EXPR so cp_gimplify_init_expr was never called!
// 93280.C
struct A {
template <typename T> A(T);
int c;
};
struct D {
A a{0};
};
void f() {
D d;
d = {};
}
// 104583.C
struct A {
A();
int c;
};
struct D {
A a{}; // #1
};
void g()
{
D d;
d = {}; // #2
}
