diff --git a/Makefile.libretro b/Makefile.libretro
index b35a0dac..f0d39857 100644
--- a/Makefile.libretro
+++ b/Makefile.libretro
@@ -436,7 +436,7 @@ else
 
 endif
 
-CFLAGS += -DNO_ZLIB
+CFLAGS += -DNO_ZLIB -D__LIBRETRO__
 
 ifeq ($(NO_MMAP),1)
 	CFLAGS += -DNO_MMAP