[libc] Swap order of syscall on chmod

[mikhailramalho]

We define SYS_fchmodat2 on libc but the syscall is not available on old kernels, so prefer the SYS_fchmodat version when possible.

[llvmbot]

@llvm/pr-subscribers-libc

Author: Mikhail R. Gadelha (mikhailramalho)

Changes

We define SYS_fchmodat2 on libc but the syscall is not available on old kernels, so prefer the SYS_fchmodat version when possible.

---

Full diff: https://github.com/llvm/llvm-project/pull/138427.diff

1 Files Affected:

• (modified) libc/src/sys/stat/linux/chmod.cpp (+3-3)

diff --git a/libc/src/sys/stat/linux/chmod.cpp b/libc/src/sys/stat/linux/chmod.cpp
index 57d5bae6b8191..1b787e47e7c68 100644
--- a/libc/src/sys/stat/linux/chmod.cpp
+++ b/libc/src/sys/stat/linux/chmod.cpp
@@ -23,12 +23,12 @@ namespace LIBC_NAMESPACE_DECL {
 LLVM_LIBC_FUNCTION(int, chmod, (const char *path, mode_t mode)) {
 #ifdef SYS_chmod
   int ret = LIBC_NAMESPACE::syscall_impl<int>(SYS_chmod, path, mode);
-#elif defined(SYS_fchmodat2)
-  int ret = LIBC_NAMESPACE::syscall_impl<int>(SYS_fchmodat2, AT_FDCWD, path,
-                                              mode, 0, AT_SYMLINK_NOFOLLOW);
 #elif defined(SYS_fchmodat)
   int ret =
       LIBC_NAMESPACE::syscall_impl<int>(SYS_fchmodat, AT_FDCWD, path, mode, 0);
+#elif defined(SYS_fchmodat2)
+  int ret = LIBC_NAMESPACE::syscall_impl<int>(SYS_fchmodat2, AT_FDCWD, path,
+                                              mode, 0, AT_SYMLINK_NOFOLLOW);
 #else
 #error "chmod, fchmodat and fchmodat2 syscalls not available."
 #endif