Structured binding initializer form { assignment-expression } fails for array type on clang

[dcl.dcl]/1 (final C++17 draft, N4659) describe the grammar of a simple-declaration as:

[...]

simple-declaration: - [...] - attribute-specifier-seq(opt) decl-specifier-seq ref-qualifier(opt) [ identifier-list ] initializer;

[dcl.dcl]/8 describes that the latter form of a simple-declaration is a structured binding declaration:

A simple-declaration with an identifier-list is called astructured binding declaration ([dcl.struct.bind]). The decl-specifier-seq shall contain only the type-specifierauto and cv-qualifier:s. The initializer shall be of the form “=assignment-expression”, of the form “{ assignment-expression }”, or of the form “( assignment-expression )”, where theassignment-expression is of array or non-union class type.

I.e., for the purpose of this question, a structured binding have the simplified grammar:

auto [ identifier-list ] initializer ;

where any of the following forms are valid initializer:s:

... = assignment-expression

... { assignment-expression }

... ( assignment-expression )

Thus, arguably the following code is well-formed:

struct S { int s; };int main() {    const S s{42};    const int arr[1] = {42};    // ... of the form “= assignment-expression”    auto[s_form1] = s;    auto[e_form1] = arr;    // ... of the form “{ assignment-expression }”    auto[s_form2]{s};    auto[e_form2]{arr};    // ... of the form “( assignment-expression )”    auto[s_form3](s);    auto[e_form3](arr);    (void)s_form1; (void)s_form2; (void)s_form3;    (void)e_form1; (void)e_form2; (void)e_form3;    return 0;}

Using both -std=c++17 and -std=c++2a, GCC (9.3) accepts this code whereas clang (10.0.0 as well as HEAD/11) rejects the "{ assignment-expression }" form for arrays:

auto[e_form2]{arr};              ^~~error: cannot initialize an array element of type 'const int'       with an lvalue of type 'const int [1]'

It fails likewise for an rvalue array:

using SingleElementIntArray = int[1];auto[e_form2]{SingleElementIntArray{42}};              ^~~~~~~~~~~~~~~~~~~~~~~~~error: cannot initialize an array element of type'int' with an rvalue of type 'SingleElementIntArray' (aka 'int [1]')

Question

• Who is right here, GCC or clang? My guess is GCC; if so, is this a known clang bug?