https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98329
Bug ID: 98329
Summary: [11 Regression] ICE in cp_build_bit_cast, at
cp/semantics.c:10730
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: gs...@t-online.de
Target Milestone: ---
Follow-up of pr98193, with test case derived from bit-cast7.C
(similar for other files bit-cast*.C).
Gives an ICE with modifications like "&from", "*from", "**from"
"-from", "--from", etc. at marker "///" :
$ cat z1.cc
template <typename To, typename From>
constexpr To
bit_cast (const From &from)
{
return __builtin_bit_cast (To, &from); ///
}
struct J
{
long int a, b : 11, h;
};
struct K
{
long int a, b : 11, c;
constexpr bool operator == (const K &x)
{
return a == x.a && b == x.b && c == x.c;
}
};
struct L
{
long long int a, b : 11, h;
};
struct M
{
long long int a, b : 11, c;
constexpr bool operator == (const M &x)
{
return a == x.a && b == x.b && c == x.c;
}
};
static_assert (bit_cast <K> (J{}) == K{}, "");
static_assert (bit_cast <M> (L{0x0feedbacdeadbeefLL}) ==
M{0x0feedbacdeadbeefLL}, "");
$ g++-11-20201213 -c z1.cc
z1.cc: In instantiation of 'constexpr To bit_cast(const From&) [with To = K;
>From = J]':
z1.cc:35:33: required from here
z1.cc:5:30: internal compiler error: Segmentation fault
5 | return __builtin_bit_cast (To, &from); ///
| ^~
0xf86f4f crash_signal
../../gcc/toplev.c:327
0x911421 cp_build_bit_cast(unsigned int, tree_node*, tree_node*, int)
../../gcc/cp/semantics.c:10730
0x89765f tsubst_copy_and_build(tree_node*, tree_node*, int, tree_node*, bool,
bool)
../../gcc/cp/pt.c:20747
0x8bca30 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc/cp/pt.c:19007
0x8bb83f tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc/cp/pt.c:18084
0x8bc9ef tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc/cp/pt.c:18398
0x8a12c5 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc/cp/pt.c:18059
0x8a12c5 instantiate_body
../../gcc/cp/pt.c:25728
0x8a2b8f instantiate_decl(tree_node*, bool, bool)
../../gcc/cp/pt.c:26017
0x6e697c instantiate_cx_fn_r
../../gcc/cp/constexpr.c:6951
0x12dbc13 walk_tree_1(tree_node**, tree_node* (*)(tree_node**, int*, void*),
void*, hash_set<tree_node*, false, default_hash_traits<tree_node*> >*,
tree_node* (*)(tree_node**, int*, tree_node* (*)(tree_node**, int*, void*),
void*, hash_set<tree_node*, false, default_hash_traits<tree_node*> >*))
../../gcc/tree.c:12095
0x12dc53d walk_tree_1(tree_node**, tree_node* (*)(tree_node**, int*, void*),
void*, hash_set<tree_node*, false, default_hash_traits<tree_node*> >*,
tree_node* (*)(tree_node**, int*, tree_node* (*)(tree_node**, int*, void*),
void*, hash_set<tree_node*, false, default_hash_traits<tree_node*> >*))
../../gcc/tree.c:12431
0x12dc478 walk_tree_1(tree_node**, tree_node* (*)(tree_node**, int*, void*),
void*, hash_set<tree_node*, false, default_hash_traits<tree_node*> >*,
tree_node* (*)(tree_node**, int*, tree_node* (*)(tree_node**, int*, void*),
void*, hash_set<tree_node*, false, default_hash_traits<tree_node*> >*))
../../gcc/tree.c:12335
0x12dc53d walk_tree_1(tree_node**, tree_node* (*)(tree_node**, int*, void*),
void*, hash_set<tree_node*, false, default_hash_traits<tree_node*> >*,
tree_node* (*)(tree_node**, int*, tree_node* (*)(tree_node**, int*, void*),
void*, hash_set<tree_node*, false, default_hash_traits<tree_node*> >*))
../../gcc/tree.c:12431
0x12e0245 walk_tree_without_duplicates_1(tree_node**, tree_node*
(*)(tree_node**, int*, void*), void*, tree_node* (*)(tree_node**, int*,
tree_node* (*)(tree_node**, int*, void*), void*, hash_set<tree_node*, false,
default_hash_traits<tree_node*> >*))
../../gcc/tree.c:12457
0x6f5858 instantiate_constexpr_fns
../../gcc/cp/constexpr.c:6971
0x6f5858 cxx_eval_outermost_constant_expr
../../gcc/cp/constexpr.c:7125
0x6fa6b4 maybe_constant_value(tree_node*, tree_node*, bool)
../../gcc/cp/constexpr.c:7381
0x90f76d finish_static_assert(tree_node*, tree_node*, unsigned int, bool, bool)
../../gcc/cp/semantics.c:9932
0x82de02 cp_parser_static_assert
../../gcc/cp/parser.c:15365
