[perl #48134] [BUG][PATCH]interp->current_args overwritten in callmethodcc

[Mehmet Yavuz Selim Soyturk]

# New Ticket Created by  "Mehmet Yavuz Selim Soyturk" 
# Please include the string:  [perl #48134]
# in the subject line of all future correspondence about this issue. 
# <URL: http://rt.perl.org/rt3/Ticket/Display.html?id=48134 >


Next code segfaults because callmethodcc does another method call,
which causes that interp->current_args gets overwritten.


.sub main :main
   $P0 = newclass 'Obj'
   $P2 = new 'Obj'
   $P2.'some_method'(42)
.end

.sub meth :method
   .param pmc a

   say a
.end

.namespace ['Obj']

.sub find_method :vtable :method
   .param string meth_name

   say meth_name

   .const .Sub meth = 'meth'
   .return (meth)
.end


I attached a patch which seems to solve the problem.

-- 
Mehmet

Index: src/ops/object.ops
===================================================================
--- src/ops/object.ops	(revision 23456)
+++ src/ops/object.ops	(working copy)
@@ -55,11 +55,17 @@
   PMC *method_pmc, *object;
   opcode_t *next;
   STRING *meth;
+  opcode_t *current_args;
 
   object = $1;
   meth = $2;
   next = expr NEXT();
+  
+  /* find_method can overwrite interp->current_args! */
+  current_args = interp->current_args;
   method_pmc = VTABLE_find_method(interp, object, meth);
+  interp->current_args = current_args;
+  
   if (PMC_IS_NULL(method_pmc)) {
     real_exception(interp, next, METH_NOT_FOUND,
         "Method '%Ss' not found", meth);
@@ -91,11 +97,17 @@
   PMC *method_pmc, *object;
   opcode_t *next;
   STRING *meth;
+  opcode_t *current_args;
 
   object = $1;
   meth = $2;
   next = expr NEXT();
+  
+  /* find_method can overwrite interp->current_args! */
+  current_args = interp->current_args;
   method_pmc = VTABLE_find_method(interp, object, meth);
+  interp->current_args = current_args;
+  
   if (PMC_IS_NULL(method_pmc)) {
     real_exception(interp, next, METH_NOT_FOUND,
         "Method '%Ss' not found", meth);