小编wha*_*ned的帖子

以下代码无法使用 Clang 13 和 MSVC v19.29 VS16.11 编译，但可以使用 GCC 11.2 成功编译。

template <typename...>
concept always_true = true;

template <typename T>
concept refable = always_true<T&>;

static_assert(refable<void>);

铿锵13：

<source>:9:1: error: static_assert failed
static_assert(refable<void>);
^             ~~~~~~~~~~~~~
<source>:9:15: note: because 'void' does not satisfy 'refable'
static_assert(refable<void>);
              ^
<source>:7:32: note: because substituted constraint expression is ill-formed: cannot form a reference to 'void'
concept refable = always_true<T&>;
                               ^

MSVC v19.29 VS16.11：

<source>(9): error C2607: static assertion failed

神箭

GCC这里错了吗？我期望refable<void>评估结果为 false，因为它void&在直接上下文中形成无效的 type( ) …