https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82514
Bug ID: 82514
Summary: [8 Regression] ICE: in operator[], at vec.h:749
Product: gcc
Version: 8.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: trippels at gcc dot gnu.org
CC: jason at gcc dot gnu.org
Target Milestone: ---
% cat minimal_product.ii
template <typename _Iftrue> struct A { typedef _Iftrue type; };
template <int, typename _Iftrue, typename>
using conditional_t = typename A<_Iftrue>::type;
struct B;
template <typename> struct ebo {};
template <bool> struct C;
template <typename, typename = void> struct tag_of;
template <typename> struct D;
struct unpack_t {
template <typename Xs, typename F>
constexpr decltype(auto) operator()(Xs &&, F &&) const;
} a;
template <typename _Tp, _Tp...> struct F;
template <typename _Tp, _Tp> using make_integer_sequence = F<_Tp>;
template <long... _Idx> using index_sequence = F<unsigned long, _Idx...>;
template <int>
using make_index_sequence = make_integer_sequence<unsigned long, 0>;
template <typename...> struct G;
template <long... n, typename... Xn>
struct G<index_sequence<n...>, Xn...> : ebo<Xn>... {};
template <typename... Xn>
struct M : G<make_index_sequence<sizeof...(Xn)>, Xn...> {};
template <typename... Xn> struct tag_of<M<Xn...>> { using type = B; };
template <> struct D<B> {
template <typename... Xn, typename F>
static auto apply(G<index_sequence<>, Xn...> p1, F p2) {
p2(static_cast<ebo<Xn>>(p1)...);
}
};
template <typename T, typename> struct tag_of : tag_of<T, C<0>> {};
template <typename T, bool condition> struct tag_of<T, C<condition>> {
using type = typename T::hana_tag;
};
template <typename T> struct tag_of<T &> : tag_of<T> {};
template <typename> struct H {
template <typename X> constexpr decltype(auto) operator()(X &&) const;
};
struct {
H<int> to;
} b;
template <typename Xs, typename F>
constexpr decltype(auto) unpack_t::operator()(Xs &&p1, F &&p2) const {
using S = typename tag_of<Xs>::type;
using Unpack = conditional_t<0, D<S>, int>;
Unpack::apply(p1, p2);
}
template <typename... Xn> struct I {
M<Xn...> storage_;
using hana_tag = int;
};
template <> struct D<int> {
template <typename Xs, typename F> static auto apply(Xs p1, F p2) {
a(p1.storage_, p2);
}
};
template <typename Algorithm>
template <typename X>
constexpr decltype(auto) H<Algorithm>::operator()(X &&) const {}
template <typename T, typename = void> struct N : N<T, C<0>> {};
struct for_each_t {
template <typename Xs, typename F>
constexpr void operator()(Xs &&, F &&) const;
} c;
template <typename Xs, typename F>
constexpr void for_each_t::operator()(Xs &&p1, F &&p2) const {
using S = typename tag_of<Xs>::type;
using ForEach = conditional_t<0, N<S>, int>;
ForEach::apply(p1, p2);
}
template <typename F> struct J {
F f;
template <typename... Xs> void operator()(Xs... p1) {
using Swallow = int;
Swallow{((*f)(p1), 0)...};
}
};
template <typename T, bool condition> struct N<T, C<condition>> {
template <typename Xs, typename F> static void apply(Xs p1, F p2) {
a(p1, J<decltype(&p2)>{});
}
};
struct K {
template <typename Foldables> K(Foldables p1) {
c(p1, [](auto) {
struct L {};
b.to(L{});
});
}
};
I<int> d;
int main() { K{d}; }
% g++ -c minimal_product.ii
minimal_product.ii: In instantiation of ‘constexpr decltype(auto) H<
<template-parameter-1-1> >::operator()(X&&) const [with X =
K::K(Foldables)::<lambda(auto:1)> [with auto:1 = ebo<int>; Foldables =
I<int>]::L; <template-parameter-1-1> = int]’:
minimal_product.ii:58:26: required from here
minimal_product.ii:58:26: internal compiler error: in operator[], at vec.h:749
constexpr decltype(auto) H<Algorithm>::operator()(X &&) const {}
^~~~~~~~~~~~
0x10362fa3 vec<tree_node*, va_gc, vl_embed>::operator[](unsigned int)
../../gcc/gcc/vec.h:749
0x10362fa3 local_class_index
../../gcc/gcc/cp/mangle.c:1894
0x1036d25b discriminator_for_local_entity
../../gcc/gcc/cp/mangle.c:1930
0x1036d25b write_local_name
../../gcc/gcc/cp/mangle.c:2031
0x1036d25b write_name
../../gcc/gcc/cp/mangle.c:964
0x10372fe3 write_encoding
../../gcc/gcc/cp/mangle.c:825
0x1036ce33 write_local_name
../../gcc/gcc/cp/mangle.c:2000
0x1036ce33 write_name
../../gcc/gcc/cp/mangle.c:964
0x1036defb write_class_enum_type
../../gcc/gcc/cp/mangle.c:2781
0x1036defb write_type
../../gcc/gcc/cp/mangle.c:2195
0x1036cb43 write_template_args
../../gcc/gcc/cp/mangle.c:2810
0x10374c83 write_nested_name
../../gcc/gcc/cp/mangle.c:1063
0x1036d047 write_name
../../gcc/gcc/cp/mangle.c:976
0x10372fe3 write_encoding
../../gcc/gcc/cp/mangle.c:825
0x10375893 mangle_decl_string
../../gcc/gcc/cp/mangle.c:3760
0x10375bfb get_mangled_id
../../gcc/gcc/cp/mangle.c:3782
0x10375bfb mangle_decl(tree_node*)
../../gcc/gcc/cp/mangle.c:3820
0x10f3024f decl_assembler_name(tree_node*)
../../gcc/gcc/tree.c:673
0x10f612eb assign_assembler_name_if_needed(tree_node*)
../../gcc/gcc/tree.c:5595
0x10690e1f cgraph_node::analyze()
../../gcc/gcc/cgraphunit.c:663
