https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118240
Marek Polacek <mpolacek at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Ever confirmed|0 |1
CC| |mpolacek at gcc dot gnu.org
Status|UNCONFIRMED |NEW
Last reconfirmed| |2025-01-06
--- Comment #1 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
```
// PR c++/103943
// { dg-do compile { target c++17 } }
template<typename R, typename...AA, typename NOS=int> struct F0 { //OK
R(*fun_ptr)(AA...);
};
template<typename R, typename...AA, int NON=0> struct F1 { //OK
R(*fun_ptr)(AA...);
F1(R(*fun_ptr)(AA...)) : fun_ptr(fun_ptr) {}
};
template<typename R, typename...AA, int NON=0> struct F2 { //OK
R(*fun_ptr)(AA...);
using fun_ptr_t = decltype(fun_ptr);
F2(fun_ptr_t fun_ptr) : fun_ptr(fun_ptr) {}
};
template<typename R, typename...AA, typename NOS=int> struct F3 {
R(*fun_ptr)(AA...);
// using fun_ptr_t = decltype(fun_ptr); //OK as in F2
using fun_ptr_t = decltype(F3::fun_ptr); //ICE: Segmentation fault
// using fun_ptr_t = decltype(F3<R, AA...>::fun_ptr); //ICE: Segmentation
fault
F3(fun_ptr_t fun_ptr) : fun_ptr(fun_ptr) {}
};
template<typename R, typename...AA, int NON=0> struct F4 {
static R fun_not_implemented(AA...);
// using fun_ptr_t = decltype(&fun_not_implemented); //OK
using fun_ptr_t = decltype(&F4::fun_not_implemented); //OK with aggregate
initialization (no ctor)
// using fun_ptr_t = decltype(&F4<R, AA...>::fun_not_implemented); //OK with
aggregate initialization (no ctor)
fun_ptr_t fun_ptr;
};
template<typename R, typename...AA, int NON=0> struct F5 { //OK
static R fun_not_implemented(AA...);
using fun_ptr_t = decltype(&fun_not_implemented);
fun_ptr_t fun_ptr;
F5(fun_ptr_t fun_ptr) : fun_ptr(fun_ptr) {}
};
template<typename R, typename...AA, int NON=0> struct F6 {
static R fun_not_implemented(AA...);
// using fun_ptr_t = decltype(&fun_not_implemented); //OK as in F5
using fun_ptr_t = decltype(&F6::fun_not_implemented); //ICE: in
build_qualified_name, at cp/tree.c:2238
// using fun_ptr_t = decltype(&F6<R, AA...>::fun_not_implemented); //ICE: in
build_qualified_name, at cp/tree.c:2238
fun_ptr_t fun_ptr;
F6(fun_ptr_t fun_ptr) : fun_ptr(fun_ptr) {}
};
template<typename R, typename...AA> F0(R(*fun_ptr)(AA...)) -> F0<R, AA...>;
template<typename R, typename...AA> F1(R(*fun_ptr)(AA...)) -> F1<R, AA...>;
template<typename R, typename...AA> F2(R(*fun_ptr)(AA...)) -> F2<R, AA...>;
template<typename R, typename...AA> F3(R(*fun_ptr)(AA...)) -> F3<R, AA...>;
template<typename R, typename...AA> F4(R(*fun_ptr)(AA...)) -> F4<R, AA...>;
template<typename R, typename...AA> F5(R(*fun_ptr)(AA...)) -> F5<R, AA...>;
template<typename R, typename...AA> F6(R(*fun_ptr)(AA...)) -> F6<R, AA...>;
int fun(int a) {
return a + 1;
}
#pragma GCC diagnostic ignored "-Wunused-but-set-variable"
void test() {
auto f0 = F0{&fun}; //OK
auto f1 = F1{&fun}; //OK
auto f2 = F2{&fun}; //OK
auto f3 = F3{&fun}; //ICE: Segmentation fault
auto f4 = F4{&fun}; //OK
auto f5 = F5{&fun}; //OK
auto f6 = F6{&fun}; //ICE: in build_qualified_name, at cp/tree.c:2238
}
```
