--- base/runtime/objs/makefile.orig	2019-11-10 14:00:54 UTC
+++ base/runtime/objs/makefile
@@ -5,10 +5,12 @@
 
 SHELL =		/bin/sh
 MAKE =		make
-CC =		cc
-CPP =		/lib/cpp
-LD_LIBS =
-AS =		as
+CC ?=		cc
+CFLAGS ?=
+CPP ?=		/lib/cpp
+LD_LIBS ?=
+AS ?=		as
+ASFLAGS ?=
 AR =		ar
 ARFLAGS =	rcv
 RANLIB =	ranlib
@@ -37,8 +39,6 @@ MP_DIR =	$(ROOT_DIR)/mp
 CLIB_DIR =	$(ROOT_DIR)/c-libs
 CONFIG_DIR =	$(ROOT_DIR)/config
 
-CFLAGS =	-O
-
 INCLUDES =	-I$(OBJS_DIR) -I$(INC_DIR)
 GC_INCLUDES =	$(INCLUDES) -I$(GC_DIR)
 GEN_INCLUDES =	-I$(CONFIG_DIR) $(INCLUDES)
@@ -275,7 +275,7 @@ prim.o:		$(MACH_DIR)/$(TARGET).prim.asm \
 		$(MACH_DIR)/x86-syntax.h \
 		mlstate-offsets.h
 	$(CPP) -D_ASM_ $(DEFS) $(INCLUDES) $(MACH_DIR)/$(TARGET).prim.asm > prim.s
-	$(AS) -o prim.o prim.s
+	$(AS) $(ASFLAGS) -o prim.o prim.s
 
 #
 #