In regcomp.c, Set_Node_Cur_Length() uses parse_start, so explicitly pass it.

The macro Set_Node_Cur_Length() had been referring to the variable
parse_start within its body. This somewhat secret reference is potentially
risky, as it was always taking a parameter node, hence one might assume that
that was all that it used, and change the value stored in parse_start.
(Specifically, one place that assigns RExC_parse - 1 to parse_start, and later
uses parse_start + 1, which looks like an obvious cleanup candidate)

So make parse_start an explicit parameter.

Also, eliminate the never-used macro Set_Cur_Node_Length. This was added as
part of commit fac927409d5ddf11 (April 2001) but never used.

diff --git a/regcomp.c b/regcomp.c
index 642f62a..ca23653 100644 (file)
--- a/regcomp.c
+++ b/regcomp.c
@@ -634,7 +634,7 @@ static const scan_data_t zero_scan_data =
 #define Set_Cur_Node_Offset
 #define Set_Node_Length_To_R(node,len)
 #define Set_Node_Length(node,len)
-#define Set_Node_Cur_Length(node)
+#define Set_Node_Cur_Length(node,start)
 #define Node_Offset(n) 
 #define Node_Length(n) 
 #define Set_Node_Offset_Length(node,offset,len)
@@ -673,9 +673,8 @@ static const scan_data_t zero_scan_data =
 
 #define Set_Node_Length(node,len) \
     Set_Node_Length_To_R((node)-RExC_emit_start, len)
-#define Set_Cur_Node_Length(len) Set_Node_Length(RExC_emit, len)
-#define Set_Node_Cur_Length(node) \
-    Set_Node_Length(node, RExC_parse - parse_start)
+#define Set_Node_Cur_Length(node, start)                \
+    Set_Node_Length(node, RExC_parse - start)
 
 /* Get offsets and lengths */
 #define Node_Offset(n) (RExC_offsets[2*((n)-RExC_emit_start)-1])
@@ -8827,7 +8826,7 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                     *flagp |= HASWIDTH;
 
                     Set_Node_Offset(ret, parse_start+1);
-                    Set_Node_Cur_Length(ret); /* MJD */
+                    Set_Node_Cur_Length(ret, parse_start);
 
                     nextchar(pRExC_state);
                     return ret;
@@ -9477,7 +9476,7 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
            if (paren == '>')
                node = SUSPEND, flag = 0;
            reginsert(pRExC_state, node,ret, depth+1);
-           Set_Node_Cur_Length(ret);
+            Set_Node_Cur_Length(ret, parse_start);
            Set_Node_Offset(ret, parse_start + 1);
            ret->flags = flag;
             REGTAIL_STUDY(pRExC_state, ret, reg_node(pRExC_state, TAIL));
@@ -9701,7 +9700,7 @@ S_regpiece(pTHX_ RExC_state_t *pRExC_state, I32 *flagp, U32 depth)
                RExC_naughty += 2 + RExC_naughty / 2;
                reginsert(pRExC_state, CURLY, ret, depth+1);
                 Set_Node_Offset(ret, parse_start+1); /* MJD */
-                Set_Node_Cur_Length(ret);
+                Set_Node_Cur_Length(ret, parse_start);
            }
            else {
                regnode * const w = reg_node(pRExC_state, WHILEM);
@@ -10583,7 +10582,7 @@ tryagain:
                RExC_parse--;
 
                Set_Node_Offset(ret, parse_start + 2);
-               Set_Node_Cur_Length(ret);
+                Set_Node_Cur_Length(ret, parse_start);
                nextchar(pRExC_state);
            }
            break;
@@ -10647,7 +10646,7 @@ tryagain:
 
                 /* override incorrect value set in reganode MJD */
                 Set_Node_Offset(ret, parse_start+1);
-                Set_Node_Cur_Length(ret); /* MJD */
+                Set_Node_Cur_Length(ret, parse_start);
                 nextchar(pRExC_state);
 
             }
@@ -10724,7 +10723,7 @@ tryagain:
 
                     /* override incorrect value set in reganode MJD */
                     Set_Node_Offset(ret, parse_start+1);
-                    Set_Node_Cur_Length(ret); /* MJD */
+                    Set_Node_Cur_Length(ret, parse_start);
                    RExC_parse--;
                    nextchar(pRExC_state);
                }
@@ -11349,7 +11348,7 @@ tryagain:
             }
 
            RExC_parse = p - 1;
-            Set_Node_Cur_Length(ret); /* MJD */
+            Set_Node_Cur_Length(ret, parse_start);
            nextchar(pRExC_state);
            {
                /* len is STRLEN which is unsigned, need to copy to signed */