diff --git a/Lua/lua-5.3.4/src/Makefile b/Lua/lua-5.3.4/src/Makefile
index 369baa1d..790d49fa 100644
--- a/Lua/lua-5.3.4/src/Makefile
+++ b/Lua/lua-5.3.4/src/Makefile
@@ -6,10 +6,11 @@
 # Your platform. See PLATS for possible values.
 PLAT= none
 
-CC= gcc -std=gnu99
-CFLAGS= -O2 -Wall -Wextra -DLUA_COMPAT_5_2 $(SYSCFLAGS) $(MYCFLAGS)
-LDFLAGS= $(SYSLDFLAGS) $(MYLDFLAGS)
-LIBS= -lm $(SYSLIBS) $(MYLIBS)
+CC ?= gcc -std=gnu99
+CFLAGS ?= -O2 -Wall -Wextra
+CFLAGS += -DLUA_COMPAT_5_2 $(SYSCFLAGS) $(MYCFLAGS)
+LDFLAGS = $(SYSLDFLAGS) $(MYLDFLAGS)
+LIBS = -lm $(SYSLIBS) $(MYLIBS)
 
 AR= ar rcu
 RANLIB= ranlib