Fix Mac build breakage.

Change-Id: I5c92053d81093cdb7810d758d568d2694038280a
diff --git a/llvm-device-build.mk b/llvm-device-build.mk
index 30baec0..3811c99 100644
--- a/llvm-device-build.mk
+++ b/llvm-device-build.mk
@@ -1,8 +1,5 @@
 LOCAL_CFLAGS :=	\
 	-D_GNU_SOURCE	\
-	-D__STDC_LIMIT_MACROS	\
-	-D__STDC_CONSTANT_MACROS	\
-	-D__STDC_FORMAT_MACROS	\
 	-O2	\
 	-fomit-frame-pointer	\
 	-Wall	\
@@ -11,6 +8,13 @@
 	-Wwrite-strings	\
 	$(LOCAL_CFLAGS)
 
+ifneq ($(HOST_OS),darwin)
+LOCAL_CFLAGS +=	\
+	-D__STDC_LIMIT_MACROS	\
+	-D__STDC_CONSTANT_MACROS	\
+	-D__STDC_FORMAT_MACROS
+endif
+
 # The three inline options together reduce libbcc.so almost 1MB.
 # We move them from global build/core/combo/TARGET_linux-arm.mk
 # to here.
diff --git a/llvm-host-build.mk b/llvm-host-build.mk
index 9fd7435..f32f8a8 100644
--- a/llvm-host-build.mk
+++ b/llvm-host-build.mk
@@ -1,8 +1,5 @@
 LOCAL_CFLAGS :=	\
 	-D_GNU_SOURCE	\
-	-D__STDC_LIMIT_MACROS	\
-	-D__STDC_CONSTANT_MACROS	\
-	-D__STDC_FORMAT_MACROS	\
 	-O2	\
 	-fomit-frame-pointer	\
 	-Wall	\
@@ -11,6 +8,13 @@
 	-Wwrite-strings	\
 	$(LOCAL_CFLAGS)
 
+ifneq ($(HOST_OS),darwin)
+LOCAL_CFLAGS +=	\
+	-D__STDC_LIMIT_MACROS	\
+	-D__STDC_CONSTANT_MACROS	\
+	-D__STDC_FORMAT_MACROS
+endif
+
 ifeq ($(LLVM_ENABLE_ASSERTION),true)
 LOCAL_CFLAGS :=	\
 	$(LOCAL_CFLAGS) \