[BUG] Object alias lowers to copy-initialization

[JohelEGP]

Title: Object alias lowers to copy-initialization.

Minimal reproducer (https://cpp2.godbolt.org/z/1ea3jsGa8):

#include <array>
arr: std::array<int, 1> == (0);
main: () = { }

Commands:

cppfront main.cpp2
clang++17 -std=c++23 -stdlib=libc++ -lc++abi -pedantic-errors -Wall -Wextra -Wconversion -Werror=unused-result -I . main.cpp

Expected result:

std::array<int,1> inline constexpr arr{0};

Actual result and error:

std::array<int,1> inline constexpr arr = (0);

Cpp2 lowered to Cpp1:

//=== Cpp2 type declarations ====================================================


#include "cpp2util.h"



//=== Cpp2 type definitions and function declarations ===========================

#include <array>
std::array<int,1> inline constexpr arr = (0);
auto main() -> int;


//=== Cpp2 function definitions =================================================


auto main() -> int{}

Output:

main.cpp2:2:36: error: no viable conversion from 'int' to 'const std::array<int, 1>'
    2 | std::array<int,1> inline constexpr arr = (0);
      |                                    ^     ~~~
/opt/compiler-explorer/clang-trunk-20230923/bin/../include/c++/v1/array:164:29: note: candidate constructor (the implicit copy constructor) not viable: no known conversion from 'int' to 'const array<int, 1> &' for 1st argument
  164 | struct _LIBCPP_TEMPLATE_VIS array
      |                             ^~~~~
/opt/compiler-explorer/clang-trunk-20230923/bin/../include/c++/v1/array:164:29: note: candidate constructor (the implicit move constructor) not viable: no known conversion from 'int' to 'array<int, 1> &&' for 1st argument
  164 | struct _LIBCPP_TEMPLATE_VIS array
      |                             ^~~~~
1 error generated.

See also:

• b589f5d#r128105347.
• [BUG] Initializer of parameterized statement parameter lowers to copy-initialization #527.