X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=mro.c;h=8634ccb3eb7e4f67ea3497e3fa675125088c4605;hb=53c40a8fd46e24a1d1e4bce188f973172eb1a279;hp=01461b145ae369ffbf09b5a64cff368df760f2a5;hpb=5be5c7a687aa37f2ea9dec7988eb57cad1f1ec24;p=p5sagit%2Fp5-mst-13.2.git

diff --git a/mro.c b/mro.c
index 01461b1..8634ccb 100644
--- a/mro.c
+++ b/mro.c
@@ -21,6 +21,7 @@ These functions are related to the method resolution order of perl classes
 */
 
 #include "EXTERN.h"
+#define PERL_IN_MRO_C
 #include "perl.h"
 
 struct mro_meta*
@@ -83,8 +84,8 @@ invalidated).
 
 =cut
 */
-AV*
-Perl_mro_get_linear_isa_dfs(pTHX_ HV *stash, I32 level)
+static AV*
+S_mro_get_linear_isa_dfs(pTHX_ HV *stash, I32 level)
 {
     AV* retval;
     GV** gvp;
@@ -113,7 +114,7 @@ Perl_mro_get_linear_isa_dfs(pTHX_ HV *stash, I32 level)
 
     /* not in cache, make a new one */
 
-    retval = newAV();
+    retval = (AV*)sv_2mortal((SV *)newAV());
     av_push(retval, newSVpv(stashname, 0)); /* add ourselves at the top */
 
     /* fetch our @ISA */
@@ -146,7 +147,10 @@ Perl_mro_get_linear_isa_dfs(pTHX_ HV *stash, I32 level)
             }
             else {
                 /* otherwise, recurse into ourselves for the MRO
-                   of this @ISA member, and append their MRO to ours */
+                   of this @ISA member, and append their MRO to ours.
+		   The recursive call could throw an exception, which
+		   has memory management implications here, hence the use of
+		   the mortal.  */
 		const AV *const subrv
 		    = mro_get_linear_isa_dfs(basestash, level + 1);
 
@@ -163,6 +167,12 @@ Perl_mro_get_linear_isa_dfs(pTHX_ HV *stash, I32 level)
         }
     }
 
+    /* now that we're past the exception dangers, grab our own reference to
+       the AV we're about to use for the result. The reference owned by the
+       mortals' stack will be released soon, so everything will balance.  */
+    SvREFCNT_inc_simple_void_NN(retval);
+    SvTEMP_off(retval);
+
     /* we don't want anyone modifying the cache entry but us,
        and we do so by replacing it completely */
     SvREADONLY_on(retval);
@@ -188,8 +198,8 @@ invalidated).
 =cut
 */
 
-AV*
-Perl_mro_get_linear_isa_c3(pTHX_ HV* stash, I32 level)
+static AV*
+S_mro_get_linear_isa_c3(pTHX_ HV* stash, I32 level)
 {
     AV* retval;
     GV** gvp;
@@ -448,10 +458,8 @@ Perl_mro_isa_changed_in(pTHX_ HV* stash)
     bool is_universal;
     struct mro_meta * meta;
 
-    const char * const stashname = stash ? HvNAME_get(stash) : NULL;
-    const STRLEN stashname_len = stash ? HvNAMELEN_get(stash) : 0;
-
-    if(!stash) return;
+    const char * const stashname = HvNAME_get(stash);
+    const STRLEN stashname_len = HvNAMELEN_get(stash);
 
     if(!stashname)
         Perl_croak(aTHX_ "Can't call mro_isa_changed_in() on anonymous symbol table");