https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99833
Bug ID: 99833
Summary: structured binding + if init + generic lambda =
internal compiler error
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: nickgray0 at brown dot edu
Target Milestone: ---
Build: -std=c++20
as the title suggests, the following code triggers an internal compiler error:
#include <tuple>
auto f(auto&& x) {
[&](auto...) {
auto y = std::tuple{ "what's happening here?", x };
if constexpr (auto [_, z] = y; requires { z; })
return;
}();
}
auto main()->int {
f(42);
}
error message: <source>:6:36: internal compiler error: in tsubst_decomp_names,
at cp/pt.c:18034
6 | if constexpr (auto [_, z] = y; requires { z; })
| ^~~~~~
0x1cfb6a9 internal_error(char const*, ...)
???:0
0x6ba871 fancy_abort(char const*, int, char const*)
???:0
0x91c84f instantiate_decl(tree_node*, bool, bool)
???:0
0x7c6c0e maybe_instantiate_decl(tree_node*)
???:0
0x7c8370 mark_used(tree_node*, int)
???:0
0x6e2835 build_op_call(tree_node*, vec<tree_node*, va_gc, vl_embed>**, int)
???:0
0x980ae5 finish_call_expr(tree_node*, vec<tree_node*, va_gc, vl_embed>**, bool,
bool, int)
???:0
0x91c84f instantiate_decl(tree_node*, bool, bool)
???:0
0x7c6c0e maybe_instantiate_decl(tree_node*)
???:0
0x7c8370 mark_used(tree_node*, int)
???:0
0x6de097 build_new_function_call(tree_node*, vec<tree_node*, va_gc,
vl_embed>**, int)
???:0
0x980c6c finish_call_expr(tree_node*, vec<tree_node*, va_gc, vl_embed>**, bool,
bool, int)
???:0
0x8e12ad c_parse_file()
???:0
0xa600a2 c_common_parse_file()
???:0
either moving the structured binding outside of if statement or making the
lambda non-generic seems to solve the problem.
