Change the context type of for ($a .. $b) to CXt_LOOP_LAZYIV, and

assert that it isn't using  cx->blk_loop.iterlval.
Fix a casting bug when assigning a sentinal to cx->blk_loop.iterary.

p4raw-id: //depot/perl@33061

5 files changed, 23 insertions, 5 deletions

diff --git a/cop.h b/cop.h
index 91290024cd..fd8e9fa04d 100644
--- a/cop.h
+++ b/cop.h
@@ -518,6 +518,8 @@ struct block_loop {
 	CX_ITERDATA_SET(cx,dat);
 
 #define POPLOOP(cx)							\
+	if (CxTYPE(cx) == CXt_LOOP_LAZYIV)				\
+	    assert(!cx->blk_loop.iterlval);				\
 	SvREFCNT_dec(cx->blk_loop.iterlval);				\
 	if (CxITERVAR(cx)) {						\
             if (SvPADMY(cx->blk_loop.itersave)) {			\
@@ -679,11 +681,12 @@ struct context {
 #define CXt_BLOCK	5
 #define CXt_FORMAT	6
 #define CXt_GIVEN	7
-#define CXt_LOOP_PLAIN	8
-#define CXt_LOOP_FOR	9
+/* This is first so that CXt_LOOP_FOR|CXt_LOOP_LAZYIV is CXt_LOOP_LAZYIV */
+#define CXt_LOOP_FOR	8
+#define CXt_LOOP_PLAIN	9
 /* Foreach on a temporary list on the stack */
 #define CXt_LOOP_STACK	10
-#define CXt_LOOP_RES2	11
+#define CXt_LOOP_LAZYIV	11
 
 /* private flags for CXt_SUB and CXt_NULL
    However, this is checked in many places which do not check the type, so
diff --git a/pp_ctl.c b/pp_ctl.c
index c0f0724a39..7968eb971e 100644
--- a/pp_ctl.c
+++ b/pp_ctl.c
@@ -1256,6 +1256,7 @@ S_dopoptolabel(pTHX_ const char *label)
 	    if (CxTYPE(cx) == CXt_NULL)
 		return -1;
 	    break;
+	case CXt_LOOP_LAZYIV:
 	case CXt_LOOP_STACK:
 	case CXt_LOOP_FOR:
 	case CXt_LOOP_PLAIN:
@@ -1373,6 +1374,7 @@ S_dopoptoloop(pTHX_ I32 startingblock)
 	    if ((CxTYPE(cx)) == CXt_NULL)
 		return -1;
 	    break;
+	case CXt_LOOP_LAZYIV:
 	case CXt_LOOP_STACK:
 	case CXt_LOOP_FOR:
 	case CXt_LOOP_PLAIN:
@@ -1399,6 +1401,7 @@ S_dopoptogiven(pTHX_ I32 startingblock)
 	case CXt_LOOP_PLAIN:
 	    assert(!CxFOREACHDEF(cx));
 	    break;
+	case CXt_LOOP_LAZYIV:
 	case CXt_LOOP_STACK:
 	case CXt_LOOP_FOR:
 	    if (CxFOREACHDEF(cx)) {
@@ -1451,6 +1454,7 @@ Perl_dounwind(pTHX_ I32 cxix)
 	case CXt_EVAL:
 	    POPEVAL(cx);
 	    break;
+	case CXt_LOOP_LAZYIV:
 	case CXt_LOOP_STACK:
 	case CXt_LOOP_FOR:
 	case CXt_LOOP_PLAIN:
@@ -1884,6 +1888,10 @@ PP(pp_enteriter)
 	    SvGETMAGIC(sv);
 	    SvGETMAGIC(right);
 	    if (RANGE_IS_NUMERIC(sv,right)) {
+		cx->cx_type |= CXt_LOOP_LAZYIV;
+		/* Make sure that no-one re-orders cop.h and breaks our
+		   assumptions */
+		assert(CxTYPE(cx) == CXt_LOOP_LAZYIV);
 #ifdef NV_PRESERVES_UV
 		if ((SvOK(sv) && ((SvNV(sv) < (NV)IV_MIN) ||
 				  (SvNV(sv) > (NV)IV_MAX)))
@@ -1924,7 +1932,7 @@ PP(pp_enteriter)
 	}
     }
     else {
-	cx->blk_loop.iterary = (SV*)0xDEADBEEF;
+	cx->blk_loop.iterary = (AV*)0xDEADBEEF;
 	if (PL_op->op_private & OPpITER_REVERSED) {
 	    cx->blk_loop.itermax = MARK - PL_stack_base + 1;
 	    cx->blk_loop.iterix = cx->blk_oldsp + 1;
@@ -2150,6 +2158,7 @@ PP(pp_last)
     cxstack_ix++; /* temporarily protect top context */
     mark = newsp;
     switch (CxTYPE(cx)) {
+    case CXt_LOOP_LAZYIV:
     case CXt_LOOP_STACK:
     case CXt_LOOP_FOR:
     case CXt_LOOP_PLAIN:
@@ -2195,6 +2204,7 @@ PP(pp_last)
     cxstack_ix--;
     /* Stack values are safe: */
     switch (pop2) {
+    case CXt_LOOP_LAZYIV:
     case CXt_LOOP_PLAIN:
     case CXt_LOOP_STACK:
     case CXt_LOOP_FOR:
@@ -2555,6 +2565,7 @@ PP(pp_goto)
 		    break;
                 }
                 /* else fall through */
+	    case CXt_LOOP_LAZYIV:
 	    case CXt_LOOP_STACK:
 	    case CXt_LOOP_FOR:
 	    case CXt_LOOP_PLAIN:
diff --git a/pp_hot.c b/pp_hot.c
index a7657f8648..ca0b4abc43 100644
--- a/pp_hot.c
+++ b/pp_hot.c
@@ -1914,7 +1914,7 @@ PP(pp_iter)
     av = CxTYPE(cx) == CXt_LOOP_STACK ? PL_curstack : cx->blk_loop.iterary;
     if (SvTYPE(av) != SVt_PVAV) {
 	/* iterate ($min .. $max) */
-	if (cx->blk_loop.iterlval) {
+	if (CxTYPE(cx) != CXt_LOOP_LAZYIV) {
 	    /* string increment */
 	    register SV* cur = cx->blk_loop.iterlval;
 	    STRLEN maxlen = 0;
@@ -1944,6 +1944,7 @@ PP(pp_iter)
 	    RETPUSHNO;
 	}
 	/* integer increment */
+	assert(!cx->blk_loop.iterlval);
 	if (cx->blk_loop.iterix > cx->blk_loop.itermax)
 	    RETPUSHNO;
 
diff --git a/scope.c b/scope.c
index 74a3be0d97..c8f190fc1c 100644
--- a/scope.c
+++ b/scope.c
@@ -1083,6 +1083,8 @@ Perl_cx_dump(pTHX_ PERL_CONTEXT *cx)
 		PTR2UV(cx->blk_eval.retop));
 	break;
 
+    case CXt_LOOP_LAZYIV:
+    case CXt_LOOP_STACK:
     case CXt_LOOP_FOR:
     case CXt_LOOP_PLAIN:
 	PerlIO_printf(Perl_debug_log, "BLK_LOOP.LABEL = %s\n", CxLABEL(cx));
diff --git a/sv.c b/sv.c
index 1feaa3e9dc..33293a5eeb 100644
--- a/sv.c
+++ b/sv.c
@@ -10542,6 +10542,7 @@ Perl_cx_dup(pTHX_ PERL_CONTEXT *cxs, I32 ix, I32 max, CLONE_PARAMS* param)
 						      param);
 		ncx->blk_eval.cur_text	= sv_dup(ncx->blk_eval.cur_text, param);
 		break;
+	    case CXt_LOOP_LAZYIV:
 	    case CXt_LOOP_FOR:
 		ncx->blk_loop.iterary	= av_dup_inc(ncx->blk_loop.iterary,
 						     param);