diff --git a/diff.c b/diff.c
index 7a03c581c7..fe3abac79f 100644
--- a/diff.c
+++ b/diff.c
@@ -3725,7 +3725,8 @@ static void builtin_diffstat(const char *name_a, const char *name_b,
 		xpp.anchors_nr = o->anchors_nr;
 		xecfg.ctxlen = o->context;
 		xecfg.interhunkctxlen = o->interhunkcontext;
-		if (xdi_diff_outf(&mf1, &mf2, discard_hunk_line,
+		xecfg.flags = XDL_EMIT_NO_HUNK_HDR;
+		if (xdi_diff_outf(&mf1, &mf2, NULL,
 				  diffstat_consume, diffstat, &xpp, &xecfg))
 			die("unable to generate diffstat for %s", one->path);
 
@@ -6233,8 +6234,8 @@ static int diff_get_patch_id(struct diff_options *options, struct object_id *oid
 
 		xpp.flags = 0;
 		xecfg.ctxlen = 3;
-		xecfg.flags = 0;
-		if (xdi_diff_outf(&mf1, &mf2, discard_hunk_line,
+		xecfg.flags = XDL_EMIT_NO_HUNK_HDR;
+		if (xdi_diff_outf(&mf1, &mf2, NULL,
 				  patch_id_consume, &data, &xpp, &xecfg))
 			return error("unable to generate patch-id diff for %s",
 				     p->one->path);
diff --git a/diffcore-pickaxe.c b/diffcore-pickaxe.c
index 96183f4cfa..c88e50c632 100644
--- a/diffcore-pickaxe.c
+++ b/diffcore-pickaxe.c
@@ -53,6 +53,7 @@ static int diff_grep(mmfile_t *one, mmfile_t *two,
 	memset(&xecfg, 0, sizeof(xecfg));
 	ecbdata.regexp = regexp;
 	ecbdata.hit = 0;
+	xecfg.flags = XDL_EMIT_NO_HUNK_HDR;
 	xecfg.ctxlen = o->context;
 	xecfg.interhunkctxlen = o->interhunkcontext;
 
@@ -60,7 +61,7 @@ static int diff_grep(mmfile_t *one, mmfile_t *two,
 	 * An xdiff error might be our "data->hit" from above. See the
 	 * comment for xdiff_emit_line_fn in xdiff-interface.h
 	 */
-	ret = xdi_diff_outf(one, two, discard_hunk_line, diffgrep_consume,
+	ret = xdi_diff_outf(one, two, NULL, diffgrep_consume,
 			    &ecbdata, &xpp, &xecfg);
 	if (ecbdata.hit)
 		return 1;
diff --git a/xdiff-interface.c b/xdiff-interface.c
index 50c0ef759d..95f13a93ff 100644
--- a/xdiff-interface.c
+++ b/xdiff-interface.c
@@ -126,12 +126,6 @@ int xdi_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp, xdemitconf_t co
 	return xdl_diff(&a, &b, xpp, xecfg, xecb);
 }
 
-void discard_hunk_line(void *priv,
-		       long ob, long on, long nb, long nn,
-		       const char *func, long funclen)
-{
-}
-
 int xdi_diff_outf(mmfile_t *mf1, mmfile_t *mf2,
 		  xdiff_emit_hunk_fn hunk_fn,
 		  xdiff_emit_line_fn line_fn,
diff --git a/xdiff-interface.h b/xdiff-interface.h
index 3b6819586d..4301a7eef2 100644
--- a/xdiff-interface.h
+++ b/xdiff-interface.h
@@ -53,14 +53,6 @@ void xdiff_clear_find_func(xdemitconf_t *xecfg);
 int git_xmerge_config(const char *var, const char *value, void *cb);
 extern int git_xmerge_style;
 
-/*
- * Can be used as a no-op hunk_fn for xdi_diff_outf(), since a NULL
- * one just sends the hunk line to the line_fn callback).
- */
-void discard_hunk_line(void *priv,
-		       long ob, long on, long nb, long nn,
-		       const char *func, long funclen);
-
 /*
  * Compare the strings l1 with l2 which are of size s1 and s2 respectively.
  * Returns 1 if the strings are deemed equal, 0 otherwise.
diff --git a/xdiff/xdiff.h b/xdiff/xdiff.h
index 7a04605146..b29deca5de 100644
--- a/xdiff/xdiff.h
+++ b/xdiff/xdiff.h
@@ -50,6 +50,7 @@ extern "C" {
 
 /* xdemitconf_t.flags */
 #define XDL_EMIT_FUNCNAMES (1 << 0)
+#define XDL_EMIT_NO_HUNK_HDR (1 << 1)
 #define XDL_EMIT_FUNCCONTEXT (1 << 2)
 
 /* merge simplification levels */
diff --git a/xdiff/xemit.c b/xdiff/xemit.c
index 9d7d6c5087..1cbf2b9829 100644
--- a/xdiff/xemit.c
+++ b/xdiff/xemit.c
@@ -278,7 +278,8 @@ int xdl_emit_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,
 				      s1 - 1, funclineprev);
 			funclineprev = s1 - 1;
 		}
-		if (xdl_emit_hunk_hdr(s1 + 1, e1 - s1, s2 + 1, e2 - s2,
+		if (!(xecfg->flags & XDL_EMIT_NO_HUNK_HDR) &&
+		    xdl_emit_hunk_hdr(s1 + 1, e1 - s1, s2 + 1, e2 - s2,
 				      func_line.buf, func_line.len, ecb) < 0)
 			return -1;