--- a/config/config.mk
+++ b/config/config.mk
@@ -287,23 +287,21 @@ CXXFLAGS	+= $(MOZ_OPTIMIZE_FLAGS)
 endif # MOZ_OPTIMIZE == 1
 LDFLAGS		+= $(MOZ_OPTIMIZE_LDFLAGS)
 endif # MOZ_OPTIMIZE
 
 HOST_CFLAGS	+= $(_DEPEND_CFLAGS)
 HOST_CXXFLAGS	+= $(_DEPEND_CFLAGS)
 ifdef CROSS_COMPILE
 HOST_CFLAGS	+= $(HOST_OPTIMIZE_FLAGS)
+HOST_CXXFLAGS	+= $(HOST_OPTIMIZE_FLAGS)
 else
 ifdef MOZ_OPTIMIZE
-ifeq (1,$(MOZ_OPTIMIZE))
 HOST_CFLAGS	+= $(MOZ_OPTIMIZE_FLAGS)
-else
-HOST_CFLAGS	+= $(MOZ_OPTIMIZE_FLAGS)
-endif # MOZ_OPTIMIZE == 1
+HOST_CXXFLAGS	+= $(MOZ_OPTIMIZE_FLAGS)
 endif # MOZ_OPTIMIZE
 endif # CROSS_COMPILE
 
 CFLAGS += $(MOZ_FRAMEPTR_FLAGS)
 CXXFLAGS += $(MOZ_FRAMEPTR_FLAGS)
 
 # Check for ALLOW_COMPILER_WARNINGS (shorthand for Makefiles to request that we
 # *don't* use the warnings-as-errors compile flags)