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[BUG] Local copy/forward parameter not moved/forwarded #825
Description
Title: Local copy/forward parameter not moved/forwarded.
Minimal reproducer (https://cpp2.godbolt.org/z/aTW719Pq7):
main: (args) = {
a := 0;
_ = a; // Moves.
_ = :(copy b) _ = b; // Doesn't move.
for args do (copy c) _ = c; // Doesn't move.
_ = :(forward d) _ = d; // Doesn't forward.
for args do (forward e) _ = e; // Doesn't forward.
}
f: (copy x) _ = x; // Moves.
f: (forward x) _ = x; // Forwards.
Commands:
cppfront main.cpp2
clang++18 -std=c++23 -stdlib=libc++ -lc++abi -pedantic-errors -Wall -Wextra -Wconversion -Werror=unused-result -I . main.cppExpected result: Same as local variable/function parameter.
Actual result and error: As indicated in the comments.
Cpp2 lowered to Cpp1:
//=== Cpp2 type declarations ====================================================
#include "cpp2util.h"
//=== Cpp2 type definitions and function declarations ===========================
auto main(int const argc_, char** argv_) -> int;
[[nodiscard]] auto f(auto x) -> auto;
[[nodiscard]] auto f(auto&& x) -> auto;
//=== Cpp2 function definitions =================================================
auto main(int const argc_, char** argv_) -> int{
auto const args = cpp2::make_args(argc_, argv_);
auto a {0};
static_cast<void>(std::move(a));// Moves.
static_cast<void>([](auto b) -> auto { return static_cast<void>(b); });// Doesn't move.
for ( auto c : args ) static_cast<void>(c); // Doesn't move.
static_cast<void>([](auto&& d) -> auto { return static_cast<void>(d); });// Doesn't forward.
for ( auto&& e : args ) static_cast<void>(e); // Doesn't forward.
}
[[nodiscard]] auto f(auto x) -> auto { return static_cast<void>(std::move(x)); }// Moves.
[[nodiscard]] auto f(auto&& x) -> auto { return static_cast<void>(CPP2_FORWARD(x)); }// Forwards.Program returned: 0
See also:
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