+#ALL_ARCH_OPTIONS = $(patsubst %,-arch %,$(subst ppc,,$(VALID_ARCHS)) )
+
+# build the list of all valid archs for this platform...
+ifeq ($(ARCH),i386)
+ ALL_ARCH_OPTIONS = $(patsubst %,-arch %,$(filter-out arm%,$(VALID_ARCHS)) )
+ SYSROOT = -isysroot $(OSX_SDK)
+endif
+ifeq ($(ARCH),x86_64)
+ ALL_ARCH_OPTIONS = $(patsubst %,-arch %,$(filter-out arm%,$(VALID_ARCHS)) )
+ SYSROOT = -isysroot $(OSX_SDK)
+endif
+ifeq ($(ARCH),armv7)
+ ALL_ARCH_OPTIONS = $(patsubst %,-arch %,$(filter arm%,$(VALID_ARCHS)) )
+ SYSROOT = -isysroot $(IOS_SDK)
+endif
+ifeq ($(ARCH),arm64)
+ ALL_ARCH_OPTIONS = $(patsubst %,-arch %,$(filter arm%,$(VALID_ARCHS)) )
+ SYSROOT = -isysroot $(IOS_SDK)
+endif