Makefile: appending existing flags instead of overwriting them

diff --git a/Makefile b/Makefile
index ea1b2e674c9a58e6587e14913d07d694e0b42b16..48d848ab9c692511e16fd4935b48293334720e3d 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
-CFLAGS := -g -O2 -fPIE -fstack-protector-strong -Wall -Wextra -Wconversion
-CPPFLAGS := -D_FORTIFY_SOURCE=2
-LDFLAGS := -fPIE -pie -Wl,-z,relro -Wl,-z,now
+CFLAGS := -g -O2 -fPIE -fstack-protector-strong -Wall -Wextra -Wconversion $(CFLAGS)
+CPPFLAGS := -D_FORTIFY_SOURCE=2 $(CPPFLAGS)
+LDFLAGS := -fPIE -pie -Wl,-z,relro -Wl,-z,now $(LDFLAGS)
 
 
 ptyas: ptyas.c