locale.c: Free over-allocated space early

We may over malloc some space in buffers to strxfrm().  This frees it
now instead of waiting for the whole block to be freed sometime later.
This can be a significant amount of memory if the input string to
strxfrm() is long.

1 files changed, 2 insertions, 0 deletions

diff --git a/locale.c b/locale.c
index 55e43b3c30..fd46a77566 100644
--- a/locale.c
+++ b/locale.c
@@ -1465,6 +1465,8 @@ Perl_mem_collxfrm(pTHX_ const char *input_string,
 
     *xlen = xout - sizeof(PL_collation_ix);
 
+    /* Free up unneeded space; retain ehough for trailing NUL */
+    Renew(xbuf, xout + 1, char);
 
     if (s != input_string) {
         Safefree(s);