diff --git a/src/bin/imlib2_conv.c b/src/bin/imlib2_conv.c
index 1b05b1f..1c46d0c 100644
--- a/src/bin/imlib2_conv.c
+++ b/src/bin/imlib2_conv.c
@@ -8,7 +8,9 @@
 #include <stdio.h>
 #include <string.h>
 
+#ifndef X_DISPLAY_MISSING
 #define X_DISPLAY_MISSING
+#endif
 #include <Imlib2.h>
 
 #define PROG_NAME "imlib2_conv"
diff --git a/src/lib/api.c b/src/lib/api.c
index cbd4e48..3bb09ea 100644
--- a/src/lib/api.c
+++ b/src/lib/api.c
@@ -10,8 +10,10 @@
 #include <X11/Xutil.h>
 #include <X11/extensions/shape.h>
 #else
+#ifndef X_DISPLAY_MISSING
 #define X_DISPLAY_MISSING
 #endif
+#endif
 
 #include "Imlib2.h"
 #include "blend.h"
diff --git a/src/lib/image.h b/src/lib/image.h
index f125e12..da82576 100644
--- a/src/lib/image.h
+++ b/src/lib/image.h
@@ -5,8 +5,10 @@
 #ifdef BUILD_X11
 #include <X11/Xlib.h>
 #else
+#ifndef X_DISPLAY_MISSING
 #define X_DISPLAY_MISSING
 #endif
+#endif
 
 #include <Imlib2.h>
 
diff --git a/src/lib/script.c b/src/lib/script.c
index f3a33b0..b65912f 100644
--- a/src/lib/script.c
+++ b/src/lib/script.c
@@ -13,8 +13,10 @@
 #ifdef BUILD_X11
 #include <X11/Xlib.h>
 #else
+#ifndef X_DISPLAY_MISSING
 #define X_DISPLAY_MISSING
 #endif
+#endif
 
 #include "dynamic_filters.h"
 #include "image.h"