1 files changed, 6 insertions, 4 deletions
diff --git a/pp_ctl.c b/pp_ctl.c
index d0033bfd99..acf6f01689 100644
--- a/pp_ctl.c
+++ b/pp_ctl.c
@@ -86,10 +86,12 @@ PP(pp_regcomp) {
     else {
 	t = SvPV(tmpstr, len);
 
-	/* JMR: Check against the last compiled regexp */
-	if ( ! pm->op_pmregexp  || ! pm->op_pmregexp->precomp
-	    || strnNE(pm->op_pmregexp->precomp, t, len) 
-	    || pm->op_pmregexp->precomp[len]) {
+	/* JMR: Check against the last compiled regexp
+	   To know for sure, we'd need the length of precomp.
+	   But we don't have it, so we must ... take a guess. */
+	if (!pm->op_pmregexp || !pm->op_pmregexp->precomp ||
+	    memNE(pm->op_pmregexp->precomp, t, len + 1))
+	{
 	    if (pm->op_pmregexp) {
 		ReREFCNT_dec(pm->op_pmregexp);
 		pm->op_pmregexp = Null(REGEXP*);	/* crucial if regcomp aborts */