请考虑以下代码:
template<typename T>
struct A { };
// same as A, but with one extra defaulted parameter
template<typename T, typename F = int>
struct B { };
template<template<typename> typename T>
T<int> build() { return {}; }
int main()
{
build<A>(); // works in gcc and clang
build<B>(); // works in gcc, does not work in clang
}
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g ++(7.3.0)编译代码就好了,但是,clang ++(5.0.1)会发出以下命令:
example.cpp:14:5: error: no matching function for call to 'build'
build<B>(); // works in gcc, does not work in clang
^~~~~~~~ …Run Code Online (Sandbox Code Playgroud)