https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64488
Bug ID: 64488
Summary: [4.9/5.0][c++11] Expand initializer list with lambdas
in variadic template. Reject valid code.
Product: gcc
Version: 5.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: reagentoo at gmail dot com
The following valid code snippet (compiled with "-std=c++11") rejected in GCC
5.0.0 (20150103) but compiles with Clang normal:
=======================================================
#include <iostream>
template <int _i>
struct Lmb
{
static void fff() { std::cout << _i << std::endl; }
};
template <int... _is>
struct Expand
{
Expand() { }
static constexpr uint m_size = sizeof...(_is);
static void (*const m_arr[m_size])();
};
template <int... _is>
void (*const Expand<_is...>::m_arr[m_size])() = {
[] () { std::cout << _is << std::endl; } ...
//Lmb<_is>::fff...
};
int main()
{
Expand<12,34,56> e;
e.m_arr[0]();
e.m_arr[1]();
e.m_arr[2]();
return 24;
}
=======================================================
GCC 5.0.0 (20150103) output:
-------------------------------------------------------
prog.cc: In lambda function:
prog.cc:20:46: error: parameter packs not expanded with '...':
[] () { std::cout << _is << std::endl; } ...
^
prog.cc:20:46: note: '_is'
prog.cc: At global scope:
prog.cc:20:50: error: expansion pattern '<lambda>' contains no argument packs
[] () { std::cout << _is << std::endl; } ...
^
