keep only one instance of hidx

src/format.c

@@ -89,6 +89,8 @@ typedef VSTAILQ_HEAD(includehead_s, inc_t) includehead_t;
 static compiled_fmt_t cformat, bformat, rformat;
 static includehead_t cincl[MAX_VSL_TAG], bincl[MAX_VSL_TAG], rincl[MAX_VSL_TAG];
 
+int hidx[MAX_VSL_TAG];
+
 /*
  * Header field names are HTTP 'tokens': ASCII except for control chars
  * and the listed separators.

src/format.h

@@ -39,7 +39,7 @@ typedef struct arg_t {
 typedef void formatter_f(const tx_t *tx, const arg_t *args, char **s,
                          size_t *len);
 
-int hidx[MAX_VSL_TAG];
+extern int hidx[MAX_VSL_TAG];
 
 char *get_payload(const rec_t *rec);
 rec_t *get_tag(const tx_t *tx, enum VSL_tag_e tag);