rust/tests/codegen/cffi/c-variadic-opt.rs
2023-07-29 18:34:41 -07:00

31 lines
881 B
Rust

// compile-flags: -C opt-level=3
#![crate_type = "lib"]
#![feature(c_variadic)]
#![no_std]
use core::ffi::VaList;
extern "C" {
fn vprintf(fmt: *const i8, ap: VaList) -> i32;
}
// Ensure that `va_start` and `va_end` are properly injected even
// when the "spoofed" `VaListImpl` is not used.
#[no_mangle]
pub unsafe extern "C" fn c_variadic_no_use(fmt: *const i8, mut ap: ...) -> i32 {
// CHECK: call void @llvm.va_start
vprintf(fmt, ap.as_va_list())
// CHECK: call void @llvm.va_end
}
// Check that `VaListImpl::clone` gets inlined into a direct call to `llvm.va_copy`
#[no_mangle]
pub unsafe extern "C" fn c_variadic_clone(fmt: *const i8, mut ap: ...) -> i32 {
// CHECK: call void @llvm.va_start
let mut ap2 = ap.clone();
// CHECK: call void @llvm.va_copy
let res = vprintf(fmt, ap2.as_va_list());
res
// CHECK: call void @llvm.va_end
}