[Bug c++/105667] [C++20] lambas in template argument sometimes causes an ICE (seg fault)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105667
Alfred Agrell changed:
What|Removed |Added
CC||blubban at gmail dot com
--- Comment #8 from Alfred Agrell ---
I ran into something similar. My reduced testcase is
struct class1
{
virtual void a_function() = 0;
};
template() {}>
class class2 {};
template
struct class3 : public class1 {
void a_function()
{
class2<> x;
}
};
struct class4 : public class3 {
class4() {}
};
https://godbolt.org/z/GKo5oWe8j
[Bug c++/105667] [C++20] lambas in template argument sometimes causes an ICE (seg fault)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105667
Eric Niebler changed:
What|Removed |Added
CC||eric.niebler at gmail dot com
--- Comment #7 from Eric Niebler ---
Another, even shorter repro:
template (B){}>
struct C {
using D = void;
};
template
using E = C<>::D;
using F = E<>;
[Bug c++/105667] [C++20] lambas in template argument sometimes causes an ICE (seg fault)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105667
Barnabás Pőcze changed:
What|Removed |Added
CC||pobrn at protonmail dot com
--- Comment #6 from Barnabás Pőcze ---
Another snippet that I believe triggers the same issue:
template
struct get { };
template
struct thing {
using T = decltype([](auto) { });
static constexpr auto value = [](auto) {
return get();
}(0);
};
thing<0> X;
---
In this case template_parms_to_args() is called with a nullptr.
template_parms_to_args (parms=0x0) at /usr/src/debug/gcc/gcc/cp/pt.cc:4912
tsubst_template_decl (t=0x77177280, args=, complain=3,
lambda_fntype=0x7717b738) at /usr/src/debug/gcc/gcc/cp/pt.cc:14543
tsubst_lambda_expr (t=, args=0x77171d80, complain=3,
in_decl=0x77173800) at /usr/src/debug/gcc/gcc/cp/pt.cc:19855
tsubst_copy_and_build (t=, args=0x77171d80,
complain=, in_decl=0x77177000, function_p=,
integral_constant_expression_p=false) at /usr/src/debug/gcc/gcc/cp/pt.cc:21446
tsubst (t=0x771760a8, args=0x77171d80, complain=3,
in_decl=0x77177000) at /usr/src/debug/gcc/gcc/cp/pt.cc:16400
tsubst_template_args (t=0x77171a20, args=args@entry=0x77171d80,
complain=complain@entry=3, in_decl=in_decl@entry=0x77177000) at
/usr/src/debug/gcc/gcc/cp/pt.cc:13580
[...]
---
GCC 12.2.0, but GCC trunk on Compiler Explorer also exhibits the same issue (as
do GCC 11.1, 11.2, 11.3, 12.1, and 12.2)
[Bug c++/105667] [C++20] lambas in template argument sometimes causes an ICE (seg fault)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105667 Martin Liška changed: What|Removed |Added CC||jason at gcc dot gnu.org, ||marxin at gcc dot gnu.org --- Comment #5 from Martin Liška --- Likely started with r9-4045-g0c1e0d63fe0ceabb, it was rejected before the revision.
[Bug c++/105667] [C++20] lambas in template argument sometimes causes an ICE (seg fault)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105667
Andrew Pinski changed:
What|Removed |Added
Status|UNCONFIRMED |NEW
Last reconfirmed||2022-05-19
Ever confirmed|0 |1
--- Comment #4 from Andrew Pinski ---
Confirmed.
Another slightly more reduced testcase:
template
struct h {typedef int type;};
template
struct t{};
template
struct crash {
using Types = typename h<[]() {}>::type;
template
static void f()
{
t b;
};
};
int main() {
crash<0>::f<1>();
return 0;
}
[Bug c++/105667] [C++20] lambas in template argument sometimes causes an ICE (seg fault)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105667
--- Comment #3 from Andrew Pinski ---
here is one which removes the inner lamba to just a templated function inside a
template struct:
template
struct h {typedef int type;};
template
struct t{};
template
struct crash {
using Types = typename h<[]() {}>::type;
template
static void f()
{
using type = t;
};
};
int main() {
crash{}.f<1>();
return 0;
}
[Bug c++/105667] [C++20] lambas in template argument sometimes causes an ICE (seg fault)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105667
Andrew Pinski changed:
What|Removed |Added
Summary|[C++20] templated lambas in |[C++20] lambas in template
|template argument sometimes |argument sometimes causes
|causes an ICE (seg fault) |an ICE (seg fault)
--- Comment #2 from Andrew Pinski ---
Confirmed. something slightly shorter, changing the class template to a
function template and changing some other things slightly too.
problem is related to lamba as a template argument.
template
struct h {typedef int type;};
template
struct t{};
template
void crash() {
using Types = typename h<[]() {}>::type;
auto f = [&] () {
using type = t;
};
f.template operator()<1>();
}
int main() {
crash();
return 0;
}
