diff --git a/mercurial/thirdparty/xdiff/xdiff.h b/mercurial/thirdparty/xdiff/xdiff.h
--- a/mercurial/thirdparty/xdiff/xdiff.h
+++ b/mercurial/thirdparty/xdiff/xdiff.h
@@ -38,20 +38,6 @@
  * (a1, a2 - a1, b1, b2 - b1) hunks */
 #define XDL_EMIT_BDIFFHUNK (1 << 4)
 
-/* merge simplification levels */
-#define XDL_MERGE_MINIMAL 0
-#define XDL_MERGE_EAGER 1
-#define XDL_MERGE_ZEALOUS 2
-#define XDL_MERGE_ZEALOUS_ALNUM 3
-
-/* merge favor modes */
-#define XDL_MERGE_FAVOR_OURS 1
-#define XDL_MERGE_FAVOR_THEIRS 2
-#define XDL_MERGE_FAVOR_UNION 3
-
-/* merge output styles */
-#define XDL_MERGE_DIFF3 1
-
 typedef struct s_mmfile {
 	char *ptr;
 	long size;
@@ -90,22 +76,6 @@
 int xdl_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp,
 	     xdemitconf_t const *xecfg, xdemitcb_t *ecb);
 
-typedef struct s_xmparam {
-	xpparam_t xpp;
-	int marker_size;
-	int level;
-	int favor;
-	int style;
-	const char *ancestor;	/* label for orig */
-	const char *file1;	/* label for mf1 */
-	const char *file2;	/* label for mf2 */
-} xmparam_t;
-
-#define DEFAULT_CONFLICT_MARKER_SIZE 7
-
-int xdl_merge(mmfile_t *orig, mmfile_t *mf1, mmfile_t *mf2,
-		xmparam_t const *xmp, mmbuffer_t *result);
-
 #ifdef __cplusplus
 }
 #endif /* #ifdef __cplusplus */
diff --git a/mercurial/thirdparty/xdiff/xmerge.c b/mercurial/thirdparty/xdiff/xmerge.c
deleted file mode 100644
--- a/mercurial/thirdparty/xdiff/xmerge.c
+++ /dev/null
@@ -1,686 +0,0 @@
-/*
- *  LibXDiff by Davide Libenzi ( File Differential Library )
- *  Copyright (C) 2003-2006 Davide Libenzi, Johannes E. Schindelin
- *
- *  This library is free software; you can redistribute it and/or
- *  modify it under the terms of the GNU Lesser General Public
- *  License as published by the Free Software Foundation; either
- *  version 2.1 of the License, or (at your option) any later version.
- *
- *  This library is distributed in the hope that it will be useful,
- *  but WITHOUT ANY WARRANTY; without even the implied warranty of
- *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- *  Lesser General Public License for more details.
- *
- *  You should have received a copy of the GNU Lesser General Public
- *  License along with this library; if not, see
- *  <http://www.gnu.org/licenses/>.
- *
- *  Davide Libenzi <davidel@xmailserver.org>
- *
- */
-
-#include "xinclude.h"
-
-typedef struct s_xdmerge {
-	struct s_xdmerge *next;
-	/*
-	 * 0 = conflict,
-	 * 1 = no conflict, take first,
-	 * 2 = no conflict, take second.
-	 * 3 = no conflict, take both.
-	 */
-	int mode;
-	/*
-	 * These point at the respective postimages.  E.g. <i1,chg1> is
-	 * how side #1 wants to change the common ancestor; if there is no
-	 * overlap, lines before i1 in the postimage of side #1 appear
-	 * in the merge result as a region touched by neither side.
-	 */
-	long i1, i2;
-	long chg1, chg2;
-	/*
-	 * These point at the preimage; of course there is just one
-	 * preimage, that is from the shared common ancestor.
-	 */
-	long i0;
-	long chg0;
-} xdmerge_t;
-
-static int xdl_append_merge(xdmerge_t **merge, int mode,
-			    long i0, long chg0,
-			    long i1, long chg1,
-			    long i2, long chg2)
-{
-	xdmerge_t *m = *merge;
-	if (m && (i1 <= m->i1 + m->chg1 || i2 <= m->i2 + m->chg2)) {
-		if (mode != m->mode)
-			m->mode = 0;
-		m->chg0 = i0 + chg0 - m->i0;
-		m->chg1 = i1 + chg1 - m->i1;
-		m->chg2 = i2 + chg2 - m->i2;
-	} else {
-		m = xdl_malloc(sizeof(xdmerge_t));
-		if (!m)
-			return -1;
-		m->next = NULL;
-		m->mode = mode;
-		m->i0 = i0;
-		m->chg0 = chg0;
-		m->i1 = i1;
-		m->chg1 = chg1;
-		m->i2 = i2;
-		m->chg2 = chg2;
-		if (*merge)
-			(*merge)->next = m;
-		*merge = m;
-	}
-	return 0;
-}
-
-static int xdl_cleanup_merge(xdmerge_t *c)
-{
-	int count = 0;
-	xdmerge_t *next_c;
-
-	/* were there conflicts? */
-	for (; c; c = next_c) {
-		if (c->mode == 0)
-			count++;
-		next_c = c->next;
-		free(c);
-	}
-	return count;
-}
-
-static int xdl_merge_cmp_lines(xdfenv_t *xe1, int i1, xdfenv_t *xe2, int i2,
-		int line_count, long flags)
-{
-	int i;
-	xrecord_t **rec1 = xe1->xdf2.recs + i1;
-	xrecord_t **rec2 = xe2->xdf2.recs + i2;
-
-	for (i = 0; i < line_count; i++) {
-		int result = xdl_recmatch(rec1[i]->ptr, rec1[i]->size,
-			rec2[i]->ptr, rec2[i]->size, flags);
-		if (!result)
-			return -1;
-	}
-	return 0;
-}
-
-static int xdl_recs_copy_0(int use_orig, xdfenv_t *xe, int i, int count, int needs_cr, int add_nl, char *dest)
-{
-	xrecord_t **recs;
-	int size = 0;
-
-	recs = (use_orig ? xe->xdf1.recs : xe->xdf2.recs) + i;
-
-	if (count < 1)
-		return 0;
-
-	for (i = 0; i < count; size += recs[i++]->size)
-		if (dest)
-			memcpy(dest + size, recs[i]->ptr, recs[i]->size);
-	if (add_nl) {
-		i = recs[count - 1]->size;
-		if (i == 0 || recs[count - 1]->ptr[i - 1] != '\n') {
-			if (needs_cr) {
-				if (dest)
-					dest[size] = '\r';
-				size++;
-			}
-
-			if (dest)
-				dest[size] = '\n';
-			size++;
-		}
-	}
-	return size;
-}
-
-static int xdl_recs_copy(xdfenv_t *xe, int i, int count, int needs_cr, int add_nl, char *dest)
-{
-	return xdl_recs_copy_0(0, xe, i, count, needs_cr, add_nl, dest);
-}
-
-static int xdl_orig_copy(xdfenv_t *xe, int i, int count, int needs_cr, int add_nl, char *dest)
-{
-	return xdl_recs_copy_0(1, xe, i, count, needs_cr, add_nl, dest);
-}
-
-/*
- * Returns 1 if the i'th line ends in CR/LF (if it is the last line and
- * has no eol, the preceding line, if any), 0 if it ends in LF-only, and
- * -1 if the line ending cannot be determined.
- */
-static int is_eol_crlf(xdfile_t *file, int i)
-{
-	long size;
-
-	if (i < file->nrec - 1)
-		/* All lines before the last *must* end in LF */
-		return (size = file->recs[i]->size) > 1 &&
-			file->recs[i]->ptr[size - 2] == '\r';
-	if (!file->nrec)
-		/* Cannot determine eol style from empty file */
-		return -1;
-	if ((size = file->recs[i]->size) &&
-			file->recs[i]->ptr[size - 1] == '\n')
-		/* Last line; ends in LF; Is it CR/LF? */
-		return size > 1 &&
-			file->recs[i]->ptr[size - 2] == '\r';
-	if (!i)
-		/* The only line has no eol */
-		return -1;
-	/* Determine eol from second-to-last line */
-	return (size = file->recs[i - 1]->size) > 1 &&
-		file->recs[i - 1]->ptr[size - 2] == '\r';
-}
-
-static int is_cr_needed(xdfenv_t *xe1, xdfenv_t *xe2, xdmerge_t *m)
-{
-	int needs_cr;
-
-	/* Match post-images' preceding, or first, lines' end-of-line style */
-	needs_cr = is_eol_crlf(&xe1->xdf2, m->i1 ? m->i1 - 1 : 0);
-	if (needs_cr)
-		needs_cr = is_eol_crlf(&xe2->xdf2, m->i2 ? m->i2 - 1 : 0);
-	/* Look at pre-image's first line, unless we already settled on LF */
-	if (needs_cr)
-		needs_cr = is_eol_crlf(&xe1->xdf1, 0);
-	/* If still undecided, use LF-only */
-	return needs_cr < 0 ? 0 : needs_cr;
-}
-
-static int fill_conflict_hunk(xdfenv_t *xe1, const char *name1,
-			      xdfenv_t *xe2, const char *name2,
-			      const char *name3,
-			      int size, int i, int style,
-			      xdmerge_t *m, char *dest, int marker_size)
-{
-	int marker1_size = (name1 ? strlen(name1) + 1 : 0);
-	int marker2_size = (name2 ? strlen(name2) + 1 : 0);
-	int marker3_size = (name3 ? strlen(name3) + 1 : 0);
-	int needs_cr = is_cr_needed(xe1, xe2, m);
-
-	if (marker_size <= 0)
-		marker_size = DEFAULT_CONFLICT_MARKER_SIZE;
-
-	/* Before conflicting part */
-	size += xdl_recs_copy(xe1, i, m->i1 - i, 0, 0,
-			      dest ? dest + size : NULL);
-
-	if (!dest) {
-		size += marker_size + 1 + needs_cr + marker1_size;
-	} else {
-		memset(dest + size, '<', marker_size);
-		size += marker_size;
-		if (marker1_size) {
-			dest[size] = ' ';
-			memcpy(dest + size + 1, name1, marker1_size - 1);
-			size += marker1_size;
-		}
-		if (needs_cr)
-			dest[size++] = '\r';
-		dest[size++] = '\n';
-	}
-
-	/* Postimage from side #1 */
-	size += xdl_recs_copy(xe1, m->i1, m->chg1, needs_cr, 1,
-			      dest ? dest + size : NULL);
-
-	if (style == XDL_MERGE_DIFF3) {
-		/* Shared preimage */
-		if (!dest) {
-			size += marker_size + 1 + needs_cr + marker3_size;
-		} else {
-			memset(dest + size, '|', marker_size);
-			size += marker_size;
-			if (marker3_size) {
-				dest[size] = ' ';
-				memcpy(dest + size + 1, name3, marker3_size - 1);
-				size += marker3_size;
-			}
-			if (needs_cr)
-				dest[size++] = '\r';
-			dest[size++] = '\n';
-		}
-		size += xdl_orig_copy(xe1, m->i0, m->chg0, needs_cr, 1,
-				      dest ? dest + size : NULL);
-	}
-
-	if (!dest) {
-		size += marker_size + 1 + needs_cr;
-	} else {
-		memset(dest + size, '=', marker_size);
-		size += marker_size;
-		if (needs_cr)
-			dest[size++] = '\r';
-		dest[size++] = '\n';
-	}
-
-	/* Postimage from side #2 */
-	size += xdl_recs_copy(xe2, m->i2, m->chg2, needs_cr, 1,
-			      dest ? dest + size : NULL);
-	if (!dest) {
-		size += marker_size + 1 + needs_cr + marker2_size;
-	} else {
-		memset(dest + size, '>', marker_size);
-		size += marker_size;
-		if (marker2_size) {
-			dest[size] = ' ';
-			memcpy(dest + size + 1, name2, marker2_size - 1);
-			size += marker2_size;
-		}
-		if (needs_cr)
-			dest[size++] = '\r';
-		dest[size++] = '\n';
-	}
-	return size;
-}
-
-static int xdl_fill_merge_buffer(xdfenv_t *xe1, const char *name1,
-				 xdfenv_t *xe2, const char *name2,
-				 const char *ancestor_name,
-				 int favor,
-				 xdmerge_t *m, char *dest, int style,
-				 int marker_size)
-{
-	int size, i;
-
-	for (size = i = 0; m; m = m->next) {
-		if (favor && !m->mode)
-			m->mode = favor;
-
-		if (m->mode == 0)
-			size = fill_conflict_hunk(xe1, name1, xe2, name2,
-						  ancestor_name,
-						  size, i, style, m, dest,
-						  marker_size);
-		else if (m->mode & 3) {
-			/* Before conflicting part */
-			size += xdl_recs_copy(xe1, i, m->i1 - i, 0, 0,
-					      dest ? dest + size : NULL);
-			/* Postimage from side #1 */
-			if (m->mode & 1) {
-				int needs_cr = is_cr_needed(xe1, xe2, m);
-
-				size += xdl_recs_copy(xe1, m->i1, m->chg1, needs_cr, (m->mode & 2),
-						      dest ? dest + size : NULL);
-			}
-			/* Postimage from side #2 */
-			if (m->mode & 2)
-				size += xdl_recs_copy(xe2, m->i2, m->chg2, 0, 0,
-						      dest ? dest + size : NULL);
-		} else
-			continue;
-		i = m->i1 + m->chg1;
-	}
-	size += xdl_recs_copy(xe1, i, xe1->xdf2.nrec - i, 0, 0,
-			      dest ? dest + size : NULL);
-	return size;
-}
-
-/*
- * Sometimes, changes are not quite identical, but differ in only a few
- * lines. Try hard to show only these few lines as conflicting.
- */
-static int xdl_refine_conflicts(xdfenv_t *xe1, xdfenv_t *xe2, xdmerge_t *m,
-		xpparam_t const *xpp)
-{
-	for (; m; m = m->next) {
-		mmfile_t t1, t2;
-		xdfenv_t xe;
-		xdchange_t *xscr, *x;
-		int i1 = m->i1, i2 = m->i2;
-
-		/* let's handle just the conflicts */
-		if (m->mode)
-			continue;
-
-		/* no sense refining a conflict when one side is empty */
-		if (m->chg1 == 0 || m->chg2 == 0)
-			continue;
-
-		/*
-		 * This probably does not work outside git, since
-		 * we have a very simple mmfile structure.
-		 */
-		t1.ptr = (char *)xe1->xdf2.recs[m->i1]->ptr;
-		t1.size = xe1->xdf2.recs[m->i1 + m->chg1 - 1]->ptr
-			+ xe1->xdf2.recs[m->i1 + m->chg1 - 1]->size - t1.ptr;
-		t2.ptr = (char *)xe2->xdf2.recs[m->i2]->ptr;
-		t2.size = xe2->xdf2.recs[m->i2 + m->chg2 - 1]->ptr
-			+ xe2->xdf2.recs[m->i2 + m->chg2 - 1]->size - t2.ptr;
-		if (xdl_do_diff(&t1, &t2, xpp, &xe) < 0)
-			return -1;
-		if (xdl_change_compact(&xe.xdf1, &xe.xdf2, xpp->flags) < 0 ||
-		    xdl_change_compact(&xe.xdf2, &xe.xdf1, xpp->flags) < 0 ||
-		    xdl_build_script(&xe, &xscr) < 0) {
-			xdl_free_env(&xe);
-			return -1;
-		}
-		if (!xscr) {
-			/* If this happens, the changes are identical. */
-			xdl_free_env(&xe);
-			m->mode = 4;
-			continue;
-		}
-		x = xscr;
-		m->i1 = xscr->i1 + i1;
-		m->chg1 = xscr->chg1;
-		m->i2 = xscr->i2 + i2;
-		m->chg2 = xscr->chg2;
-		while (xscr->next) {
-			xdmerge_t *m2 = xdl_malloc(sizeof(xdmerge_t));
-			if (!m2) {
-				xdl_free_env(&xe);
-				xdl_free_script(x);
-				return -1;
-			}
-			xscr = xscr->next;
-			m2->next = m->next;
-			m->next = m2;
-			m = m2;
-			m->mode = 0;
-			m->i1 = xscr->i1 + i1;
-			m->chg1 = xscr->chg1;
-			m->i2 = xscr->i2 + i2;
-			m->chg2 = xscr->chg2;
-		}
-		xdl_free_env(&xe);
-		xdl_free_script(x);
-	}
-	return 0;
-}
-
-static int line_contains_alnum(const char *ptr, long size)
-{
-	while (size--)
-		if (isalnum((unsigned char)*(ptr++)))
-			return 1;
-	return 0;
-}
-
-static int lines_contain_alnum(xdfenv_t *xe, int i, int chg)
-{
-	for (; chg; chg--, i++)
-		if (line_contains_alnum(xe->xdf2.recs[i]->ptr,
-				xe->xdf2.recs[i]->size))
-			return 1;
-	return 0;
-}
-
-/*
- * This function merges m and m->next, marking everything between those hunks
- * as conflicting, too.
- */
-static void xdl_merge_two_conflicts(xdmerge_t *m)
-{
-	xdmerge_t *next_m = m->next;
-	m->chg1 = next_m->i1 + next_m->chg1 - m->i1;
-	m->chg2 = next_m->i2 + next_m->chg2 - m->i2;
-	m->next = next_m->next;
-	free(next_m);
-}
-
-/*
- * If there are less than 3 non-conflicting lines between conflicts,
- * it appears simpler -- because it takes up less (or as many) lines --
- * if the lines are moved into the conflicts.
- */
-static int xdl_simplify_non_conflicts(xdfenv_t *xe1, xdmerge_t *m,
-				      int simplify_if_no_alnum)
-{
-	int result = 0;
-
-	if (!m)
-		return result;
-	for (;;) {
-		xdmerge_t *next_m = m->next;
-		int begin, end;
-
-		if (!next_m)
-			return result;
-
-		begin = m->i1 + m->chg1;
-		end = next_m->i1;
-
-		if (m->mode != 0 || next_m->mode != 0 ||
-		    (end - begin > 3 &&
-		     (!simplify_if_no_alnum ||
-		      lines_contain_alnum(xe1, begin, end - begin)))) {
-			m = next_m;
-		} else {
-			result++;
-			xdl_merge_two_conflicts(m);
-		}
-	}
-}
-
-/*
- * level == 0: mark all overlapping changes as conflict
- * level == 1: mark overlapping changes as conflict only if not identical
- * level == 2: analyze non-identical changes for minimal conflict set
- * level == 3: analyze non-identical changes for minimal conflict set, but
- *             treat hunks not containing any letter or number as conflicting
- *
- * returns < 0 on error, == 0 for no conflicts, else number of conflicts
- */
-static int xdl_do_merge(xdfenv_t *xe1, xdchange_t *xscr1,
-		xdfenv_t *xe2, xdchange_t *xscr2,
-		xmparam_t const *xmp, mmbuffer_t *result)
-{
-	xdmerge_t *changes, *c;
-	xpparam_t const *xpp = &xmp->xpp;
-	const char *const ancestor_name = xmp->ancestor;
-	const char *const name1 = xmp->file1;
-	const char *const name2 = xmp->file2;
-	int i0, i1, i2, chg0, chg1, chg2;
-	int level = xmp->level;
-	int style = xmp->style;
-	int favor = xmp->favor;
-
-	if (style == XDL_MERGE_DIFF3) {
-		/*
-		 * "diff3 -m" output does not make sense for anything
-		 * more aggressive than XDL_MERGE_EAGER.
-		 */
-		if (XDL_MERGE_EAGER < level)
-			level = XDL_MERGE_EAGER;
-	}
-
-	c = changes = NULL;
-
-	while (xscr1 && xscr2) {
-		if (!changes)
-			changes = c;
-		if (xscr1->i1 + xscr1->chg1 < xscr2->i1) {
-			i0 = xscr1->i1;
-			i1 = xscr1->i2;
-			i2 = xscr2->i2 - xscr2->i1 + xscr1->i1;
-			chg0 = xscr1->chg1;
-			chg1 = xscr1->chg2;
-			chg2 = xscr1->chg1;
-			if (xdl_append_merge(&c, 1,
-					     i0, chg0, i1, chg1, i2, chg2)) {
-				xdl_cleanup_merge(changes);
-				return -1;
-			}
-			xscr1 = xscr1->next;
-			continue;
-		}
-		if (xscr2->i1 + xscr2->chg1 < xscr1->i1) {
-			i0 = xscr2->i1;
-			i1 = xscr1->i2 - xscr1->i1 + xscr2->i1;
-			i2 = xscr2->i2;
-			chg0 = xscr2->chg1;
-			chg1 = xscr2->chg1;
-			chg2 = xscr2->chg2;
-			if (xdl_append_merge(&c, 2,
-					     i0, chg0, i1, chg1, i2, chg2)) {
-				xdl_cleanup_merge(changes);
-				return -1;
-			}
-			xscr2 = xscr2->next;
-			continue;
-		}
-		if (level == XDL_MERGE_MINIMAL || xscr1->i1 != xscr2->i1 ||
-				xscr1->chg1 != xscr2->chg1 ||
-				xscr1->chg2 != xscr2->chg2 ||
-				xdl_merge_cmp_lines(xe1, xscr1->i2,
-					xe2, xscr2->i2,
-					xscr1->chg2, xpp->flags)) {
-			/* conflict */
-			int off = xscr1->i1 - xscr2->i1;
-			int ffo = off + xscr1->chg1 - xscr2->chg1;
-
-			i0 = xscr1->i1;
-			i1 = xscr1->i2;
-			i2 = xscr2->i2;
-			if (off > 0) {
-				i0 -= off;
-				i1 -= off;
-			}
-			else
-				i2 += off;
-			chg0 = xscr1->i1 + xscr1->chg1 - i0;
-			chg1 = xscr1->i2 + xscr1->chg2 - i1;
-			chg2 = xscr2->i2 + xscr2->chg2 - i2;
-			if (ffo < 0) {
-				chg0 -= ffo;
-				chg1 -= ffo;
-			} else
-				chg2 += ffo;
-			if (xdl_append_merge(&c, 0,
-					     i0, chg0, i1, chg1, i2, chg2)) {
-				xdl_cleanup_merge(changes);
-				return -1;
-			}
-		}
-
-		i1 = xscr1->i1 + xscr1->chg1;
-		i2 = xscr2->i1 + xscr2->chg1;
-
-		if (i1 >= i2)
-			xscr2 = xscr2->next;
-		if (i2 >= i1)
-			xscr1 = xscr1->next;
-	}
-	while (xscr1) {
-		if (!changes)
-			changes = c;
-		i0 = xscr1->i1;
-		i1 = xscr1->i2;
-		i2 = xscr1->i1 + xe2->xdf2.nrec - xe2->xdf1.nrec;
-		chg0 = xscr1->chg1;
-		chg1 = xscr1->chg2;
-		chg2 = xscr1->chg1;
-		if (xdl_append_merge(&c, 1,
-				     i0, chg0, i1, chg1, i2, chg2)) {
-			xdl_cleanup_merge(changes);
-			return -1;
-		}
-		xscr1 = xscr1->next;
-	}
-	while (xscr2) {
-		if (!changes)
-			changes = c;
-		i0 = xscr2->i1;
-		i1 = xscr2->i1 + xe1->xdf2.nrec - xe1->xdf1.nrec;
-		i2 = xscr2->i2;
-		chg0 = xscr2->chg1;
-		chg1 = xscr2->chg1;
-		chg2 = xscr2->chg2;
-		if (xdl_append_merge(&c, 2,
-				     i0, chg0, i1, chg1, i2, chg2)) {
-			xdl_cleanup_merge(changes);
-			return -1;
-		}
-		xscr2 = xscr2->next;
-	}
-	if (!changes)
-		changes = c;
-	/* refine conflicts */
-	if (XDL_MERGE_ZEALOUS <= level &&
-	    (xdl_refine_conflicts(xe1, xe2, changes, xpp) < 0 ||
-	     xdl_simplify_non_conflicts(xe1, changes,
-					XDL_MERGE_ZEALOUS < level) < 0)) {
-		xdl_cleanup_merge(changes);
-		return -1;
-	}
-	/* output */
-	if (result) {
-		int marker_size = xmp->marker_size;
-		int size = xdl_fill_merge_buffer(xe1, name1, xe2, name2,
-						 ancestor_name,
-						 favor, changes, NULL, style,
-						 marker_size);
-		result->ptr = xdl_malloc(size);
-		if (!result->ptr) {
-			xdl_cleanup_merge(changes);
-			return -1;
-		}
-		result->size = size;
-		xdl_fill_merge_buffer(xe1, name1, xe2, name2,
-				      ancestor_name, favor, changes,
-				      result->ptr, style, marker_size);
-	}
-	return xdl_cleanup_merge(changes);
-}
-
-int xdl_merge(mmfile_t *orig, mmfile_t *mf1, mmfile_t *mf2,
-		xmparam_t const *xmp, mmbuffer_t *result)
-{
-	xdchange_t *xscr1, *xscr2;
-	xdfenv_t xe1, xe2;
-	int status;
-	xpparam_t const *xpp = &xmp->xpp;
-
-	result->ptr = NULL;
-	result->size = 0;
-
-	if (xdl_do_diff(orig, mf1, xpp, &xe1) < 0) {
-		return -1;
-	}
-	if (xdl_do_diff(orig, mf2, xpp, &xe2) < 0) {
-		xdl_free_env(&xe1);
-		return -1;
-	}
-	if (xdl_change_compact(&xe1.xdf1, &xe1.xdf2, xpp->flags) < 0 ||
-	    xdl_change_compact(&xe1.xdf2, &xe1.xdf1, xpp->flags) < 0 ||
-	    xdl_build_script(&xe1, &xscr1) < 0) {
-		xdl_free_env(&xe1);
-		return -1;
-	}
-	if (xdl_change_compact(&xe2.xdf1, &xe2.xdf2, xpp->flags) < 0 ||
-	    xdl_change_compact(&xe2.xdf2, &xe2.xdf1, xpp->flags) < 0 ||
-	    xdl_build_script(&xe2, &xscr2) < 0) {
-		xdl_free_script(xscr1);
-		xdl_free_env(&xe1);
-		xdl_free_env(&xe2);
-		return -1;
-	}
-	status = 0;
-	if (!xscr1) {
-		result->ptr = xdl_malloc(mf2->size);
-		memcpy(result->ptr, mf2->ptr, mf2->size);
-		result->size = mf2->size;
-	} else if (!xscr2) {
-		result->ptr = xdl_malloc(mf1->size);
-		memcpy(result->ptr, mf1->ptr, mf1->size);
-		result->size = mf1->size;
-	} else {
-		status = xdl_do_merge(&xe1, xscr1,
-				      &xe2, xscr2,
-				      xmp, result);
-	}
-	xdl_free_script(xscr1);
-	xdl_free_script(xscr2);
-
-	xdl_free_env(&xe1);
-	xdl_free_env(&xe2);
-
-	return status;
-}
diff --git a/setup.py b/setup.py
--- a/setup.py
+++ b/setup.py
@@ -850,7 +850,6 @@
 
 xdiff_srcs = [
     'mercurial/thirdparty/xdiff/xdiffi.c',
-    'mercurial/thirdparty/xdiff/xmerge.c',
     'mercurial/thirdparty/xdiff/xprepare.c',
     'mercurial/thirdparty/xdiff/xutils.c',
 ]