[BUG] Missing declaration in initializer of constexpr variable

[JohelEGP]

Title: Missing declaration in initializer of constexpr variable.

Minimal reproducer (https://cpp2.godbolt.org/z/vqsP8drv8):

f :== :() = {
  x := 0;
  if (x) {
    _ = 0;
  }
};
main: () = { }

Commands:

cppfront main.cpp2
clang++18 -std=c++23 -stdlib=libc++ -lc++abi -pedantic-errors -Wall -Wextra -Wconversion -Werror=unused-result -I . main.cpp

Expected result: x to be declared in the emitted lambda expression.

Actual result and error:

auto inline constexpr f = []() -> void{if ((std::move(x))) {static_cast<void>(0);}};

Cpp2 lowered to Cpp1:

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


#include "cpp2util.h"



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

auto inline constexpr f = []() -> void{if ((std::move(x))) {static_cast<void>(0);}};
  

auto main() -> int;


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


auto main() -> int{}

Output:

build/main.cpp:12:55: error: use of undeclared identifier 'x'
   12 | auto inline constexpr f = []() -> void{if ((std::move(x))) {static_cast<void>(0);}};
      |                                                       ^
1 error generated.

[hsutter]

Thanks! Fixed.