-# BeOS/Haiku/AmigaOS4 standard library headers create warnings
-ifneq ($(TARGET),beos)
- ifneq ($(TARGET),AmigaOS)
+# BeOS/Haiku/AmigaOS standard library headers create warnings
+ifneq ($(BUILD),i586-pc-haiku)
+ ifneq ($(findstring amigaos,$(BUILD)),amigaos)