Stop 'sub a { // }; %::=()' panicing because the backreference array

became lost.

p4raw-id: //depot/perl@26546

diff --git a/hv.c b/hv.c
index 27c4bec..c90fbb2 100644 (file)
--- a/hv.c
+++ b/hv.c
@@ -1652,6 +1652,7 @@ S_hfreeentries(pTHX_ HV *hv)
     I32 riter;
     I32 max;
     struct xpvhv_aux *iter;
+    AV *new_backrefs = NULL;
 
     if (!HvARRAY(hv))
        return;
@@ -1670,6 +1671,7 @@ S_hfreeentries(pTHX_ HV *hv)
            if (AvFILLp(iter->xhv_backreferences) == -1) {
                /* Turns out that the array is empty. Just free it.  */
                SvREFCNT_dec(iter->xhv_backreferences);
+
            } else {
                sv_magic((SV*)hv, (SV*)iter->xhv_backreferences,
                         PERL_MAGIC_backref, NULL, 0);
@@ -1708,8 +1710,21 @@ S_hfreeentries(pTHX_ HV *hv)
           the array set to 0.  */
        assert(HvARRAY(hv));
 
-       if (HvAUX(hv)->xhv_name)
+       if(HvAUX(hv)->xhv_backreferences) {
+           if (iter) {
+               /* Erk. They caused the backreference AV to be put back
+                  into the hash aux structure */
+               assert (!iter->xhv_backreferences);
+               iter->xhv_backreferences = HvAUX(hv)->xhv_backreferences;
+           } else {
+               /* Erk. They created a backreference array when there was none
+                  before.  */
+               new_backrefs = HvAUX(hv)->xhv_backreferences;
+           }
+       }
+       if (HvAUX(hv)->xhv_name) {
            unshare_hek_or_pvn(HvAUX(hv)->xhv_name, 0, 0, 0);
+       }
        /* SvOOK_off calls sv_backoff, which isn't correct.  */
 
        Safefree(HvARRAY(hv));
@@ -1731,6 +1746,11 @@ S_hfreeentries(pTHX_ HV *hv)
     }
 
     HvARRAY(hv) = array;
+
+    if (new_backrefs) {
+       /* Don't lose the backreferences array  */
+       *Perl_hv_backreferences_p(aTHX_ hv) = new_backrefs;
+    }
 }
 
 /*