https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66924
Bug ID: 66924
Summary: Bad diagnostic for parameter name used as non-type
template argument
Product: gcc
Version: 5.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: david.godfrey99 at gmail dot com
Target Milestone: ---
GCC does not give a good diagnostic for the following code:
template<int>
constexpr int variable{};
int main() {
auto f = [] (int x) -> decltype(variable<x>) {return{};};
}
The error is
error: parse error in template argument list
auto f = [] (int x) -> decltype(variable<x>) {return{};};
^
main.cpp:5:37: error: template argument 1 is invalid
This code is ill-formed, but the error should explain how x is not a constant
expression (as parameter names are never constant expressions).
