Add c flag when invoking ar (#241)

`llvm-ar` warns when the archive does not exist and `c` is not passed.

diff --git a/Makefile b/Makefile
index 467a77a864416f8d73347ac491c3193a52c6c49f..1e5d398596665882fc20be021400a7931fc926be 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -78,7 +78,7 @@ utf8proc.o: utf8proc.h utf8proc.c utf8proc_data.c
 
 libutf8proc.a: utf8proc.o
        rm -f libutf8proc.a
-       $(AR) rs libutf8proc.a utf8proc.o
+       $(AR) crs libutf8proc.a utf8proc.o
 
 libutf8proc.so.$(MAJOR).$(MINOR).$(PATCH): utf8proc.o
        $(CC) $(LDFLAGS) $(LDFLAG_SHARED) -o $@ $(SOFLAG) -Wl,libutf8proc.so.$(MAJOR) utf8proc.o