diff --git a/Makefile b/Makefile
index 5c073b36ca18..71d31e20238c 100644
--- a/Makefile
+++ b/Makefile
@@ -107,7 +107,7 @@ LIBPATH := -L ../../tools/agbcc/lib
 LIB := $(LIBPATH) -lgcc -lc -L../../libagbsyscall -lagbsyscall
 else
 CC1              = $(shell $(PATH_MODERNCC) --print-prog-name=cc1) -quiet
-override CFLAGS += -mthumb -mthumb-interwork -O2 -mabi=apcs-gnu -mtune=arm7tdmi -march=armv4t -fno-toplevel-reorder -Wno-pointer-to-int-cast
+override CFLAGS += -mthumb -mthumb-interwork -Ofast -mabi=aapcs -mtune=arm7tdmi -march=armv4t -Wno-pointer-to-int-cast
 ROM := $(MODERN_ROM_NAME)
 OBJ_DIR := $(MODERN_OBJ_DIR_NAME)
 LIBPATH := -L "$(dir $(shell $(PATH_MODERNCC) -mthumb -print-file-name=libgcc.a))" -L "$(dir $(shell $(PATH_MODERNCC) -mthumb -print-file-name=libnosys.a))" -L "$(dir $(shell $(PATH_MODERNCC) -mthumb -print-file-name=libc.a))"
@@ -297,7 +297,9 @@ $(C_BUILDDIR)/record_mixing.o: CFLAGS += -ffreestanding
 $(C_BUILDDIR)/librfu_intr.o: CC1 := tools/agbcc/bin/agbcc_arm$(EXE)
 $(C_BUILDDIR)/librfu_intr.o: CFLAGS := -O2 -mthumb-interwork -quiet
 else
-$(C_BUILDDIR)/librfu_intr.o: CFLAGS := -mthumb-interwork -O2 -mabi=apcs-gnu -mtune=arm7tdmi -march=armv4t -fno-toplevel-reorder -Wno-pointer-to-int-cast
+$(C_BUILDDIR)/librfu_intr.o: CFLAGS := -mthumb-interwork -Ofast -mabi=aapcs -mtune=arm7tdmi -march=armv4t -fno-toplevel-reorder -Wno-pointer-to-int-cast
+$(C_BUILDDIR)/m4a.o: CFLAGS := -mthumb -mthumb-interwork -Ofast -mabi=aapcs -mtune=arm7tdmi -march=armv4t -fno-toplevel-reorder -Wno-pointer-to-int-cast
+$(C_BUILDDIR)/agb_flash.o: CFLAGS := -mthumb -mthumb-interwork -Ofast -mabi=aapcs -mtune=arm7tdmi -march=armv4t -fno-toplevel-reorder -Wno-pointer-to-int-cast
 endif
 
 ifeq ($(DINFO),1)