make pp_goto() cope potential stack reallocation in EXTEND

The code for goto &foo had local pointers to the stack that
pointed to the wrong place after a realloc.

p4raw-id: //depot/perl@23217

1 files changed, 8 insertions, 11 deletions

diff --git a/pp_ctl.c b/pp_ctl.c
index 4ba11712f1..f07d7162b8 100644
--- a/pp_ctl.c
+++ b/pp_ctl.c
@@ -2267,16 +2267,13 @@ PP(pp_goto)
 	    TOPBLOCK(cx);
 	    if (CxREALEVAL(cx))
 		DIE(aTHX_ "Can't goto subroutine from an eval-string");
-	    mark = PL_stack_sp;
 	    if (CxTYPE(cx) == CXt_SUB && cx->blk_sub.hasargs) {
 		/* put @_ back onto stack */
 		AV* av = cx->blk_sub.argarray;
 		
 		items = AvFILLp(av) + 1;
-		PL_stack_sp++;
-		EXTEND(PL_stack_sp, items); /* @_ could have been extended. */
-		Copy(AvARRAY(av), PL_stack_sp, items, SV*);
-		PL_stack_sp += items;
+		EXTEND(SP, items+1); /* @_ could have been extended. */
+		Copy(AvARRAY(av), SP + 1, items, SV*);
 		SvREFCNT_dec(GvAV(PL_defgv));
 		GvAV(PL_defgv) = cx->blk_sub.savearray;
 		/* abandon @_ if it got reified */
@@ -2294,11 +2291,11 @@ PP(pp_goto)
 		AV* av;
 		av = GvAV(PL_defgv);
 		items = AvFILLp(av) + 1;
-		PL_stack_sp++;
-		EXTEND(PL_stack_sp, items); /* @_ could have been extended. */
-		Copy(AvARRAY(av), PL_stack_sp, items, SV*);
-		PL_stack_sp += items;
+		EXTEND(SP, items+1); /* @_ could have been extended. */
+		Copy(AvARRAY(av), SP + 1, items, SV*);
 	    }
+	    mark = SP;
+	    SP += items;
 	    if (CxTYPE(cx) == CXt_SUB &&
 		!(CvDEPTH(cx->blk_sub.cv) = cx->blk_sub.olddepth))
 		SvREFCNT_dec(cx->blk_sub.cv);
@@ -2331,9 +2328,9 @@ PP(pp_goto)
 		    SV **newsp;
 		    I32 gimme;
 
-		    PL_stack_sp--;		/* There is no cv arg. */
 		    /* Push a mark for the start of arglist */
 		    PUSHMARK(mark);
+		    PUTBACK;
 		    (void)(*CvXSUB(cv))(aTHX_ cv);
 		    /* Pop the current context like a decent sub should */
 		    POPBLOCK(cx, PL_curpm);
@@ -2372,7 +2369,6 @@ PP(pp_goto)
 		    GvAV(PL_defgv) = (AV*)SvREFCNT_inc(av);
 		    CX_CURPAD_SAVE(cx->blk_sub);
 		    cx->blk_sub.argarray = av;
-		    ++mark;
 
 		    if (items >= AvMAX(av) + 1) {
 			ary = AvALLOC(av);
@@ -2387,6 +2383,7 @@ PP(pp_goto)
 			    SvPVX(av) = (char*)ary;
 			}
 		    }
+		    ++mark;
 		    Copy(mark,AvARRAY(av),items,SV*);
 		    AvFILLp(av) = items - 1;
 		    assert(!AvREAL(av));