From 1b0cc4503e14932e5f14167102cb2504b7af69da Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Wed, 27 Nov 2019 20:54:30 +0000
Subject: [PATCH] REG_STARTEND is not portable, but it turns out we don't
 actually need it. From Evan Green, GitHub issue 1982.

---
 regsub.c | 22 +++++++++++-----------
 1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/regsub.c b/regsub.c
index 89355bef..8de3fa3a 100644
--- a/regsub.c
+++ b/regsub.c
@@ -77,10 +77,7 @@ regsub(const char *pattern, const char *with, const char *text, int flags)
 	end = strlen(text);
 
 	while (start <= end) {
-		m[0].rm_so = start;
-		m[0].rm_eo = end;
-
-		if (regexec(&r, text, nitems(m), m, REG_STARTEND) != 0) {
+		if (regexec(&r, text + start, nitems(m), m, 0) != 0) {
 			regsub_copy(&buf, &len, text, start, end);
 			break;
 		}
@@ -89,22 +86,25 @@ regsub(const char *pattern, const char *with, const char *text, int flags)
 		 * Append any text not part of this match (from the end of the
 		 * last match).
 		 */
-		regsub_copy(&buf, &len, text, last, m[0].rm_so);
+		regsub_copy(&buf, &len, text, last, m[0].rm_so + start);
 
 		/*
 		 * If the last match was empty and this one isn't (it is either
 		 * later or has matched text), expand this match. If it is
 		 * empty, move on one character and try again from there.
 		 */
-		if (empty || m[0].rm_so != last || m[0].rm_so != m[0].rm_eo) {
-			regsub_expand(&buf, &len, with, text, m, nitems(m));
+		if (empty ||
+		    start + m[0].rm_so != last ||
+		    m[0].rm_so != m[0].rm_eo) {
+			regsub_expand(&buf, &len, with, text + start, m,
+			    nitems(m));
 
-			last = m[0].rm_eo;
-			start = m[0].rm_eo;
+			last = start + m[0].rm_eo;
+			start += m[0].rm_eo;
 			empty = 0;
 		} else {
-			last = m[0].rm_eo;
-			start = m[0].rm_eo + 1;
+			last = start + m[0].rm_eo;
+			start += m[0].rm_eo + 1;
 			empty = 1;
 		}
 	}