https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86703
Nicolas Lesser <blitzrakete at gmail dot com> changed:
What |Removed |Added
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CC| |blitzrakete at gmail dot com
--- Comment #1 from Nicolas Lesser <blitzrakete at gmail dot com> ---
Here's another reduce example.:
struct X {};
template <auto> using Auto = X;
template <typename T> constexpr Auto<(T(), 0)> match() { return {}; }
X x = match<int>();
Without ", 0" the example compiles. Error message:
main.cpp:5:18: error: no matching function for call to ‘match<int>()’
X x = match<int>();
^
main.cpp:4:48: note: candidate: ‘template<class T> constexpr Auto<(T(), 0)>
match()’
template <typename T> constexpr Auto<(T(), 0)> match() { return {}; }
^~~~~
main.cpp:4:48: note: template argument deduction/substitution failed:
main.cpp: In substitution of ‘template<auto <anonymous> > using Auto = X [with
auto <anonymous> = ((void)0, 0)]’:
main.cpp:4:48: required by substitution of ‘template<class T> constexpr
Auto<(T(), 0)> match() [with T = int]’
main.cpp:5:18: required from here
main.cpp:4:48: error: integral expression ‘((void)0, 0)’ is not constant
main.cpp:4:48: error: trying to instantiate ‘template<auto <anonymous> >
using Auto = X’
