diff --git a/config_cortex_m4.mk b/config_cortex_m4.mk
index 1a3b7ae..7ec6269 100644
--- a/config_cortex_m4.mk
+++ b/config_cortex_m4.mk
@@ -16,7 +16,6 @@
 OPT_CFLAGS = -fdata-sections -ffunction-sections
 
 PLATFORM_CFLAGS = -Wno-unused-parameter -nostdinc -ffreestanding -fno-builtin -fsigned-char -fno-common -Wno-main -I$(shell $(CC) -print-search-dirs | $(AWK) '$$1 == "install:" {print $$NF}')include
-PLATFORM_CFLAGS += -DARM_MATH_CM4
 
 PLATFORM_CXXFLAGS = $(PLATFORM_CFLAGS)
 PLATFORM_LDFLAGS = -nostdlib -nostartfiles -nodefaultlibs -Wl,-static,-gc-sections