diff --git a/CMakeLists.txt b/CMakeLists.txt
index c56e883f24..a026af7a1a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -27,6 +27,9 @@ if(CMAKE_SYSTEM_NAME STREQUAL "Darwin")
   if(CMAKE_COMPILER_IS_GNUCXX)
     set(CMAKE_INCLUDE_SYSTEM_FLAG_CXX "-isystem ")
   endif()
+
+  # Enable fixing case-insensitive filenames for Mac.
+  set(USE_FNAME_CASE TRUE)
 endif()
 
 # Set available build types for CMake GUIs.
diff --git a/config/config.h.in b/config/config.h.in
index 8f3d154553..382b5c653d 100644
--- a/config/config.h.in
+++ b/config/config.h.in
@@ -15,7 +15,6 @@
 
 #cmakedefine HAVE__NSGETENVIRON
 #cmakedefine HAVE_CRT_EXTERNS_H
-#cmakedefine HAVE_DIRENT_H
 #cmakedefine HAVE_FCNTL_H
 #cmakedefine HAVE_FD_CLOEXEC
 #cmakedefine HAVE_FSEEKO
@@ -60,6 +59,7 @@
 #define SIGRETURN return
 #define TIME_WITH_SYS_TIME 1
 #cmakedefine UNIX
+#cmakedefine USE_FNAME_CASE
 #define USEMAN_S 1
 
 #define FEAT_BROWSE
diff --git a/src/nvim/os_unix_defs.h b/src/nvim/os_unix_defs.h
index 4ffd23aa25..24b069b090 100644
--- a/src/nvim/os_unix_defs.h
+++ b/src/nvim/os_unix_defs.h
@@ -44,25 +44,6 @@
 # define SIGDUMMYARG
 #endif
 
-#ifdef HAVE_DIRENT_H
-# include <dirent.h>
-# ifndef NAMLEN
-#  define NAMLEN(dirent) strlen((dirent)->d_name)
-# endif
-#else
-# define dirent direct
-# define NAMLEN(dirent) (dirent)->d_namlen
-# if HAVE_SYS_NDIR_H
-#  include <sys/ndir.h>
-# endif
-# if HAVE_SYS_DIR_H
-#  include <sys/dir.h>
-# endif
-# if HAVE_NDIR_H
-#  include <ndir.h>
-# endif
-#endif
-
 #if !defined(HAVE_SYS_TIME_H) || defined(TIME_WITH_SYS_TIME)
 # include <time.h>          /* on some systems time.h should not be
                                included together with sys/time.h */