macos current_exe using directly libc instead.

Author: devnexen

std/Cargo.toml

@@ -16,7 +16,7 @@ cfg-if = { version = "0.1.8", features = ['rustc-dep-of-std'] }
 panic_unwind = { path = "../panic_unwind", optional = true }
 panic_abort = { path = "../panic_abort" }
 core = { path = "../core" }
-libc = { version = "0.2.93", default-features = false, features = ['rustc-dep-of-std'] }
+libc = { version = "0.2.98", default-features = false, features = ['rustc-dep-of-std'] }
 compiler_builtins = { version = "0.1.44" }
 profiler_builtins = { path = "../profiler_builtins", optional = true }
 unwind = { path = "../unwind" }

std/src/sys/unix/os.rs

@@ -350,17 +350,14 @@ pub fn current_exe() -> io::Result<PathBuf> {
 
 #[cfg(any(target_os = "macos", target_os = "ios"))]
 pub fn current_exe() -> io::Result<PathBuf> {
-    extern "C" {
-        fn _NSGetExecutablePath(buf: *mut libc::c_char, bufsize: *mut u32) -> libc::c_int;
-    }
     unsafe {
         let mut sz: u32 = 0;
-        _NSGetExecutablePath(ptr::null_mut(), &mut sz);
+        libc::_NSGetExecutablePath(ptr::null_mut(), &mut sz);
         if sz == 0 {
             return Err(io::Error::last_os_error());
         }
         let mut v: Vec<u8> = Vec::with_capacity(sz as usize);
-        let err = _NSGetExecutablePath(v.as_mut_ptr() as *mut i8, &mut sz);
+        let err = libc::_NSGetExecutablePath(v.as_mut_ptr() as *mut i8, &mut sz);
         if err != 0 {
             return Err(io::Error::last_os_error());
         }