diff --git a/libc/src/sys/stat/linux/mkdir.cpp b/libc/src/sys/stat/linux/mkdir.cpp
--- a/libc/src/sys/stat/linux/mkdir.cpp
+++ b/libc/src/sys/stat/linux/mkdir.cpp
@@ -21,7 +21,7 @@
 LLVM_LIBC_FUNCTION(int, mkdir, (const char *path, mode_t mode)) {
 #ifdef SYS_mkdir
   long ret = __llvm_libc::syscall(SYS_mkdir, path, mode);
-#elif defined(SYS_unlinkat)
+#elif defined(SYS_mkdirat)
   long ret = __llvm_libc::syscall(SYS_mkdirat, AT_FDCWD, path, mode);
 #else
 #error "mkdir and mkdirat syscalls not available."
diff --git a/libc/src/sys/stat/linux/mkdirat.cpp b/libc/src/sys/stat/linux/mkdirat.cpp
--- a/libc/src/sys/stat/linux/mkdirat.cpp
+++ b/libc/src/sys/stat/linux/mkdirat.cpp
@@ -18,7 +18,7 @@
 namespace __llvm_libc {
 
 LLVM_LIBC_FUNCTION(int, mkdirat, (int dfd, const char *path, mode_t mode)) {
-#ifdef SYS_unlinkat
+#ifdef SYS_mkdirat
   long ret = __llvm_libc::syscall(SYS_mkdirat, dfd, path, mode);
 #else
 #error "mkdirat syscalls not available."