diff --git a/add-interactive.c b/add-interactive.c
index ae1839c04a..00a0f6f96f 100644
--- a/add-interactive.c
+++ b/add-interactive.c
@@ -724,7 +724,7 @@ static int run_update(struct add_i_state *s, const struct pathspec *ps,
 }
 
 static void revert_from_diff(struct diff_queue_struct *q,
-			     struct diff_options *opt, void *data)
+			     struct diff_options *opt, void *data UNUSED)
 {
 	int i, add_flags = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
 
diff --git a/apply.c b/apply.c
index eec2da2b03..8c7ae3f714 100644
--- a/apply.c
+++ b/apply.c
@@ -2913,7 +2913,7 @@ static int apply_one_fragment(struct apply_state *state,
 			break;
 		case ' ':
 			if (plen && (ws_rule & WS_BLANK_AT_EOF) &&
-			    ws_blank_line(patch + 1, plen, ws_rule))
+			    ws_blank_line(patch + 1, plen))
 				is_blank_context = 1;
 			/* fallthrough */
 		case '-':
@@ -2942,7 +2942,7 @@ static int apply_one_fragment(struct apply_state *state,
 				      (first == '+' ? 0 : LINE_COMMON));
 			if (first == '+' &&
 			    (ws_rule & WS_BLANK_AT_EOF) &&
-			    ws_blank_line(patch + 1, plen, ws_rule))
+			    ws_blank_line(patch + 1, plen))
 				added_blank_line = 1;
 			break;
 		case '@': case '\\':
diff --git a/blob.c b/blob.c
index 182718aba9..8f83523b0c 100644
--- a/blob.c
+++ b/blob.c
@@ -13,8 +13,7 @@ struct blob *lookup_blob(struct repository *r, const struct object_id *oid)
 	return object_as_type(obj, OBJ_BLOB, 0);
 }
 
-int parse_blob_buffer(struct blob *item, void *buffer, unsigned long size)
+void parse_blob_buffer(struct blob *item)
 {
 	item->object.parsed = 1;
-	return 0;
 }
diff --git a/blob.h b/blob.h
index 1664872055..74555c90c4 100644
--- a/blob.h
+++ b/blob.h
@@ -11,8 +11,6 @@ struct blob {
 
 struct blob *lookup_blob(struct repository *r, const struct object_id *oid);
 
-int parse_blob_buffer(struct blob *item, void *buffer, unsigned long size);
-
 /**
  * Blobs do not contain references to other objects and do not have
  * structured data that needs parsing. However, code may use the
@@ -21,5 +19,6 @@ int parse_blob_buffer(struct blob *item, void *buffer, unsigned long size);
  * parse_blob_buffer() is used (by object.c) to flag that the object
  * has been read successfully from the database.
  **/
+void parse_blob_buffer(struct blob *item);
 
 #endif /* BLOB_H */
diff --git a/builtin/add.c b/builtin/add.c
index 76277df326..190d1a692a 100644
--- a/builtin/add.c
+++ b/builtin/add.c
@@ -88,7 +88,7 @@ static int fix_unmerged_status(struct diff_filepair *p,
 }
 
 static void update_callback(struct diff_queue_struct *q,
-			    struct diff_options *opt, void *cbdata)
+			    struct diff_options *opt UNUSED, void *cbdata)
 {
 	int i;
 	struct update_callback_data *data = cbdata;
diff --git a/builtin/fast-export.c b/builtin/fast-export.c
index 3b3314e7b2..39a890fc00 100644
--- a/builtin/fast-export.c
+++ b/builtin/fast-export.c
@@ -409,7 +409,7 @@ static const char *anonymize_oid(const char *oid_hex)
 }
 
 static void show_filemodify(struct diff_queue_struct *q,
-			    struct diff_options *options, void *data)
+			    struct diff_options *options UNUSED, void *data)
 {
 	int i;
 	struct string_list *changed = data;
diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c
index e3767087bb..ae2c011681 100644
--- a/builtin/merge-tree.c
+++ b/builtin/merge-tree.c
@@ -98,7 +98,7 @@ static void *origin(struct merge_list *entry, unsigned long *size)
 	return NULL;
 }
 
-static int show_outf(void *priv_, mmbuffer_t *mb, int nbuf)
+static int show_outf(void *priv UNUSED, mmbuffer_t *mb, int nbuf)
 {
 	int i;
 	for (i = 0; i < nbuf; i++)
diff --git a/builtin/merge.c b/builtin/merge.c
index dd474371a2..17b41fbe38 100644
--- a/builtin/merge.c
+++ b/builtin/merge.c
@@ -776,7 +776,7 @@ static int try_merge_strategy(const char *strategy, struct commit_list *common,
 }
 
 static void count_diff_files(struct diff_queue_struct *q,
-			     struct diff_options *opt, void *data)
+			     struct diff_options *opt UNUSED, void *data)
 {
 	int *count = data;
 
diff --git a/builtin/rerere.c b/builtin/rerere.c
index 8b7392d5b4..94ffb8c21a 100644
--- a/builtin/rerere.c
+++ b/builtin/rerere.c
@@ -14,7 +14,7 @@ static const char * const rerere_usage[] = {
 	NULL,
 };
 
-static int outf(void *dummy, mmbuffer_t *ptr, int nbuf)
+static int outf(void *dummy UNUSED, mmbuffer_t *ptr, int nbuf)
 {
 	int i;
 	for (i = 0; i < nbuf; i++)
diff --git a/builtin/reset.c b/builtin/reset.c
index 1fa86edb4c..d2e0185e55 100644
--- a/builtin/reset.c
+++ b/builtin/reset.c
@@ -133,7 +133,8 @@ static void print_new_head_line(struct commit *commit)
 }
 
 static void update_index_from_diff(struct diff_queue_struct *q,
-		struct diff_options *opt, void *data)
+				   struct diff_options *opt UNUSED,
+				   void *data)
 {
 	int i;
 	int intent_to_add = *(int *)data;
diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 05f2c9bc98..6743fb27bd 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -1043,7 +1043,7 @@ static void prepare_submodule_summary(struct summary_cb *info,
 }
 
 static void submodule_summary_callback(struct diff_queue_struct *q,
-				       struct diff_options *options,
+				       struct diff_options *options UNUSED,
 				       void *data)
 {
 	int i;
diff --git a/cache.h b/cache.h
index 07d40b0964..fcf49706ad 100644
--- a/cache.h
+++ b/cache.h
@@ -1865,7 +1865,7 @@ unsigned ws_check(const char *line, int len, unsigned ws_rule);
 void ws_check_emit(const char *line, int len, unsigned ws_rule, FILE *stream, const char *set, const char *reset, const char *ws);
 char *whitespace_error_string(unsigned ws);
 void ws_fix_copy(struct strbuf *, const char *, int, unsigned, int *);
-int ws_blank_line(const char *line, int len, unsigned ws_rule);
+int ws_blank_line(const char *line, int len);
 #define ws_tab_width(rule)     ((rule) & WS_TAB_WIDTH_MASK)
 
 /* ls-files */
diff --git a/combine-diff.c b/combine-diff.c
index b0ece95480..1a39b5dde0 100644
--- a/combine-diff.c
+++ b/combine-diff.c
@@ -372,7 +372,7 @@ struct combine_diff_state {
 static void consume_hunk(void *state_,
 			 long ob, long on,
 			 long nb, long nn,
-			 const char *funcline, long funclen)
+			 const char *func UNUSED, long funclen UNUSED)
 {
 	struct combine_diff_state *state = state_;
 
diff --git a/diff-lib.c b/diff-lib.c
index 2edea41a23..dec040c366 100644
--- a/diff-lib.c
+++ b/diff-lib.c
@@ -673,7 +673,7 @@ int index_differs_from(struct repository *r,
 	return (has_changes != 0);
 }
 
-static struct strbuf *idiff_prefix_cb(struct diff_options *opt, void *data)
+static struct strbuf *idiff_prefix_cb(struct diff_options *opt UNUSED, void *data)
 {
 	return data;
 }
diff --git a/diff.c b/diff.c
index 3117fce39b..6a5ed216de 100644
--- a/diff.c
+++ b/diff.c
@@ -604,7 +604,7 @@ static unsigned long diff_filespec_size(struct repository *r,
 	return one->size;
 }
 
-static int count_trailing_blank(mmfile_t *mf, unsigned ws_rule)
+static int count_trailing_blank(mmfile_t *mf)
 {
 	char *ptr = mf->ptr;
 	long size = mf->size;
@@ -622,7 +622,7 @@ static int count_trailing_blank(mmfile_t *mf, unsigned ws_rule)
 		for (prev_eol = ptr; mf->ptr <= prev_eol; prev_eol--)
 			if (*prev_eol == '\n')
 				break;
-		if (!ws_blank_line(prev_eol + 1, ptr - prev_eol, ws_rule))
+		if (!ws_blank_line(prev_eol + 1, ptr - prev_eol))
 			break;
 		cnt++;
 		ptr = prev_eol - 1;
@@ -634,9 +634,8 @@ static void check_blank_at_eof(mmfile_t *mf1, mmfile_t *mf2,
 			       struct emit_callback *ecbdata)
 {
 	int l1, l2, at;
-	unsigned ws_rule = ecbdata->ws_rule;
-	l1 = count_trailing_blank(mf1, ws_rule);
-	l2 = count_trailing_blank(mf2, ws_rule);
+	l1 = count_trailing_blank(mf1);
+	l2 = count_trailing_blank(mf2);
 	if (l2 <= l1) {
 		ecbdata->blank_at_eof_in_preimage = 0;
 		ecbdata->blank_at_eof_in_postimage = 0;
@@ -1583,7 +1582,7 @@ static int new_blank_line_at_eof(struct emit_callback *ecbdata, const char *line
 	      ecbdata->blank_at_eof_in_preimage <= ecbdata->lno_in_preimage &&
 	      ecbdata->blank_at_eof_in_postimage <= ecbdata->lno_in_postimage))
 		return 0;
-	return ws_blank_line(line, len, ecbdata->ws_rule);
+	return ws_blank_line(line, len);
 }
 
 static void emit_add_line(struct emit_callback *ecbdata,
@@ -1955,7 +1954,7 @@ static int color_words_output_graph_prefix(struct diff_words_data *diff_words)
 static void fn_out_diff_words_aux(void *priv,
 				  long minus_first, long minus_len,
 				  long plus_first, long plus_len,
-				  const char *func, long funclen)
+				  const char *func UNUSED, long funclen UNUSED)
 {
 	struct diff_words_data *diff_words = priv;
 	struct diff_words_style *style = diff_words->style;
@@ -3185,8 +3184,9 @@ static int is_conflict_marker(const char *line, int marker_size, unsigned long l
 }
 
 static void checkdiff_consume_hunk(void *priv,
-				   long ob, long on, long nb, long nn,
-				   const char *func, long funclen)
+				   long ob UNUSED, long on UNUSED,
+				   long nb, long nn UNUSED,
+				   const char *func UNUSED, long funclen UNUSED)
 
 {
 	struct checkdiff_t *data = priv;
diff --git a/list-objects-filter.c b/list-objects-filter.c
index dfc3f49f4f..7ed21cb299 100644
--- a/list-objects-filter.c
+++ b/list-objects-filter.c
@@ -70,13 +70,13 @@ struct filter {
 };
 
 static enum list_objects_filter_result filter_blobs_none(
-	struct repository *r,
+	struct repository *r UNUSED,
 	enum list_objects_filter_situation filter_situation,
 	struct object *obj,
-	const char *pathname,
-	const char *filename,
+	const char *pathname UNUSED,
+	const char *filename UNUSED,
 	struct oidset *omits,
-	void *filter_data_)
+	void *filter_data_ UNUSED)
 {
 	switch (filter_situation) {
 	default:
@@ -112,7 +112,7 @@ static enum list_objects_filter_result filter_blobs_none(
 }
 
 static void filter_blobs_none__init(
-	struct list_objects_filter_options *filter_options,
+	struct list_objects_filter_options *filter_options UNUSED,
 	struct filter *filter)
 {
 	filter->filter_object_fn = filter_blobs_none;
@@ -159,11 +159,11 @@ static int filter_trees_update_omits(
 }
 
 static enum list_objects_filter_result filter_trees_depth(
-	struct repository *r,
+	struct repository *r UNUSED,
 	enum list_objects_filter_situation filter_situation,
 	struct object *obj,
-	const char *pathname,
-	const char *filename,
+	const char *pathname UNUSED,
+	const char *filename UNUSED,
 	struct oidset *omits,
 	void *filter_data_)
 {
@@ -274,8 +274,8 @@ static enum list_objects_filter_result filter_blobs_limit(
 	struct repository *r,
 	enum list_objects_filter_situation filter_situation,
 	struct object *obj,
-	const char *pathname,
-	const char *filename,
+	const char *pathname UNUSED,
+	const char *filename UNUSED,
 	struct oidset *omits,
 	void *filter_data_)
 {
@@ -555,12 +555,12 @@ struct filter_object_type_data {
 };
 
 static enum list_objects_filter_result filter_object_type(
-	struct repository *r,
+	struct repository *r UNUSED,
 	enum list_objects_filter_situation filter_situation,
 	struct object *obj,
-	const char *pathname,
-	const char *filename,
-	struct oidset *omits,
+	const char *pathname UNUSED,
+	const char *filename UNUSED,
+	struct oidset *omits UNUSED,
 	void *filter_data_)
 {
 	struct filter_object_type_data *filter_data = filter_data_;
@@ -676,7 +676,7 @@ static enum list_objects_filter_result filter_combine(
 	struct object *obj,
 	const char *pathname,
 	const char *filename,
-	struct oidset *omits,
+	struct oidset *omits UNUSED,
 	void *filter_data)
 {
 	struct combine_filter_data *d = filter_data;
diff --git a/list-objects.c b/list-objects.c
index 250d9de41c..7528fe1db2 100644
--- a/list-objects.c
+++ b/list-objects.c
@@ -81,36 +81,6 @@ static void process_blob(struct traversal_context *ctx,
 	strbuf_setlen(path, pathlen);
 }
 
-/*
- * Processing a gitlink entry currently does nothing, since
- * we do not recurse into the subproject.
- *
- * We *could* eventually add a flag that actually does that,
- * which would involve:
- *  - is the subproject actually checked out?
- *  - if so, see if the subproject has already been added
- *    to the alternates list, and add it if not.
- *  - process the commit (or tag) the gitlink points to
- *    recursively.
- *
- * However, it's unclear whether there is really ever any
- * reason to see superprojects and subprojects as such a
- * "unified" object pool (potentially resulting in a totally
- * humongous pack - avoiding which was the whole point of
- * having gitlinks in the first place!).
- *
- * So for now, there is just a note that we *could* follow
- * the link, and how to do it. Whether it necessarily makes
- * any sense what-so-ever to ever do that is another issue.
- */
-static void process_gitlink(struct traversal_context *ctx,
-			    const unsigned char *sha1,
-			    struct strbuf *path,
-			    const char *name)
-{
-	/* Nothing to do */
-}
-
 static void process_tree(struct traversal_context *ctx,
 			 struct tree *tree,
 			 struct strbuf *base,
@@ -149,8 +119,7 @@ static void process_tree_contents(struct traversal_context *ctx,
 			process_tree(ctx, t, base, entry.path);
 		}
 		else if (S_ISGITLINK(entry.mode))
-			process_gitlink(ctx, entry.oid.hash,
-					base, entry.path);
+			; /* ignore gitlink */
 		else {
 			struct blob *b = lookup_blob(ctx->revs->repo, &entry.oid);
 			if (!b) {
diff --git a/ls-refs.c b/ls-refs.c
index fb6769742c..697d4beb8d 100644
--- a/ls-refs.c
+++ b/ls-refs.c
@@ -194,8 +194,9 @@ int ls_refs(struct repository *r, struct packet_reader *request)
 	send_possibly_unborn_head(&data);
 	if (!data.prefixes.nr)
 		strvec_push(&data.prefixes, "");
-	for_each_fullref_in_prefixes(get_git_namespace(), data.prefixes.v,
-				     send_ref, &data);
+	refs_for_each_fullref_in_prefixes(get_main_ref_store(r),
+					  get_git_namespace(), data.prefixes.v,
+					  send_ref, &data);
 	packet_fflush(stdout);
 	strvec_clear(&data.prefixes);
 	strbuf_release(&data.buf);
diff --git a/object.c b/object.c
index 682b852a46..344087de4d 100644
--- a/object.c
+++ b/object.c
@@ -212,8 +212,7 @@ struct object *parse_object_buffer(struct repository *r, const struct object_id
 	if (type == OBJ_BLOB) {
 		struct blob *blob = lookup_blob(r, oid);
 		if (blob) {
-			if (parse_blob_buffer(blob, buffer, size))
-				return NULL;
+			parse_blob_buffer(blob);
 			obj = &blob->object;
 		}
 	} else if (type == OBJ_TREE) {
@@ -292,7 +291,7 @@ struct object *parse_object_with_flags(struct repository *r,
 			error(_("hash mismatch %s"), oid_to_hex(oid));
 			return NULL;
 		}
-		parse_blob_buffer(lookup_blob(r, oid), NULL, 0);
+		parse_blob_buffer(lookup_blob(r, oid));
 		return lookup_object(r, oid);
 	}
 
diff --git a/range-diff.c b/range-diff.c
index 8b7d81adc1..8255ab4349 100644
--- a/range-diff.c
+++ b/range-diff.c
@@ -269,14 +269,18 @@ static void find_exact_matches(struct string_list *a, struct string_list *b)
 	hashmap_clear(&map);
 }
 
-static int diffsize_consume(void *data, char *line, unsigned long len)
+static int diffsize_consume(void *data,
+			     char *line UNUSED,
+			     unsigned long len UNUSED)
 {
 	(*(int *)data)++;
 	return 0;
 }
 
-static void diffsize_hunk(void *data, long ob, long on, long nb, long nn,
-			  const char *funcline, long funclen)
+static void diffsize_hunk(void *data,
+			  long ob UNUSED, long on UNUSED,
+			  long nb UNUSED, long nn UNUSED,
+			  const char *func UNUSED, long funclen UNUSED)
 {
 	diffsize_consume(data, NULL, 0);
 }
@@ -461,7 +465,7 @@ static void patch_diff(const char *a, const char *b,
 	diff_flush(diffopt);
 }
 
-static struct strbuf *output_prefix_cb(struct diff_options *opt, void *data)
+static struct strbuf *output_prefix_cb(struct diff_options *opt UNUSED, void *data)
 {
 	return data;
 }
diff --git a/ref-filter.c b/ref-filter.c
index 9dc2cd1451..971303683b 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -2128,8 +2128,9 @@ static int for_each_fullref_in_pattern(struct ref_filter *filter,
 		return for_each_fullref_in("", cb, cb_data);
 	}
 
-	return for_each_fullref_in_prefixes(NULL, filter->name_patterns,
-					    cb, cb_data);
+	return refs_for_each_fullref_in_prefixes(get_main_ref_store(the_repository),
+						 NULL, filter->name_patterns,
+						 cb, cb_data);
 }
 
 /*
diff --git a/refs.c b/refs.c
index 2c7e88b190..e31dbcda59 100644
--- a/refs.c
+++ b/refs.c
@@ -1723,9 +1723,10 @@ static void find_longest_prefixes(struct string_list *out,
 	strbuf_release(&prefix);
 }
 
-int for_each_fullref_in_prefixes(const char *namespace,
-				 const char **patterns,
-				 each_ref_fn fn, void *cb_data)
+int refs_for_each_fullref_in_prefixes(struct ref_store *ref_store,
+				      const char *namespace,
+				      const char **patterns,
+				      each_ref_fn fn, void *cb_data)
 {
 	struct string_list prefixes = STRING_LIST_INIT_DUP;
 	struct string_list_item *prefix;
@@ -1740,7 +1741,7 @@ int for_each_fullref_in_prefixes(const char *namespace,
 
 	for_each_string_list_item(prefix, &prefixes) {
 		strbuf_addstr(&buf, prefix->string);
-		ret = for_each_fullref_in(buf.buf, fn, cb_data);
+		ret = refs_for_each_fullref_in(ref_store, buf.buf, fn, cb_data);
 		if (ret)
 			break;
 		strbuf_setlen(&buf, namespace_len);
diff --git a/refs.h b/refs.h
index 3266fd8f57..935cdd1ece 100644
--- a/refs.h
+++ b/refs.h
@@ -354,8 +354,10 @@ int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data);
  *
  * callers should be prepared to ignore references that they did not ask for.
  */
-int for_each_fullref_in_prefixes(const char *namespace, const char **patterns,
-				 each_ref_fn fn, void *cb_data);
+int refs_for_each_fullref_in_prefixes(struct ref_store *refs,
+				      const char *namespace, const char **patterns,
+				      each_ref_fn fn, void *cb_data);
+
 /**
  * iterate refs from the respective area.
  */
diff --git a/revision.c b/revision.c
index 439e34a7c5..ec441b80ef 100644
--- a/revision.c
+++ b/revision.c
@@ -600,10 +600,12 @@ static struct commit *one_relevant_parent(const struct rev_info *revs,
 static int tree_difference = REV_TREE_SAME;
 
 static void file_add_remove(struct diff_options *options,
-		    int addremove, unsigned mode,
-		    const struct object_id *oid,
-		    int oid_valid,
-		    const char *fullpath, unsigned dirty_submodule)
+		    int addremove,
+		    unsigned mode UNUSED,
+		    const struct object_id *oid UNUSED,
+		    int oid_valid UNUSED,
+		    const char *fullpath UNUSED,
+		    unsigned dirty_submodule UNUSED)
 {
 	int diff = addremove == '+' ? REV_TREE_NEW : REV_TREE_OLD;
 	struct rev_info *revs = options->change_fn_data;
@@ -614,12 +616,15 @@ static void file_add_remove(struct diff_options *options,
 }
 
 static void file_change(struct diff_options *options,
-		 unsigned old_mode, unsigned new_mode,
-		 const struct object_id *old_oid,
-		 const struct object_id *new_oid,
-		 int old_oid_valid, int new_oid_valid,
-		 const char *fullpath,
-		 unsigned old_dirty_submodule, unsigned new_dirty_submodule)
+		 unsigned old_mode UNUSED,
+		 unsigned new_mode UNUSED,
+		 const struct object_id *old_oid UNUSED,
+		 const struct object_id *new_oid UNUSED,
+		 int old_oid_valid UNUSED,
+		 int new_oid_valid UNUSED,
+		 const char *fullpath UNUSED,
+		 unsigned old_dirty_submodule UNUSED,
+		 unsigned new_dirty_submodule UNUSED)
 {
 	tree_difference = REV_TREE_DIFFERENT;
 	options->flags.has_changes = 1;
diff --git a/submodule.c b/submodule.c
index 8ac2fca855..fae24ef34a 100644
--- a/submodule.c
+++ b/submodule.c
@@ -832,7 +832,7 @@ static void changed_submodule_data_clear(struct changed_submodule_data *cs_data)
 }
 
 static void collect_changed_submodules_cb(struct diff_queue_struct *q,
-					  struct diff_options *options,
+					  struct diff_options *options UNUSED,
 					  void *data)
 {
 	struct collect_changed_submodules_cb_data *me = data;
diff --git a/userdiff.c b/userdiff.c
index 151d9a5278..e25356a061 100644
--- a/userdiff.c
+++ b/userdiff.c
@@ -315,7 +315,8 @@ struct find_by_namelen_data {
 };
 
 static int userdiff_find_by_namelen_cb(struct userdiff_driver *driver,
-				       enum userdiff_driver_type type, void *priv)
+				       enum userdiff_driver_type type UNUSED,
+				       void *priv)
 {
 	struct find_by_namelen_data *cb_data = priv;
 
diff --git a/ws.c b/ws.c
index 6e69877f25..46a77bcad6 100644
--- a/ws.c
+++ b/ws.c
@@ -252,7 +252,7 @@ unsigned ws_check(const char *line, int len, unsigned ws_rule)
 	return ws_check_emit_1(line, len, ws_rule, NULL, NULL, NULL, NULL);
 }
 
-int ws_blank_line(const char *line, int len, unsigned ws_rule)
+int ws_blank_line(const char *line, int len)
 {
 	/*
 	 * We _might_ want to treat CR differently from other
diff --git a/wt-status.c b/wt-status.c
index 5813174896..76e37a8088 100644
--- a/wt-status.c
+++ b/wt-status.c
@@ -438,7 +438,7 @@ static char short_submodule_status(struct wt_status_change_data *d)
 }
 
 static void wt_status_collect_changed_cb(struct diff_queue_struct *q,
-					 struct diff_options *options,
+					 struct diff_options *options UNUSED,
 					 void *data)
 {
 	struct wt_status *s = data;
@@ -525,7 +525,7 @@ static int unmerged_mask(struct index_state *istate, const char *path)
 }
 
 static void wt_status_collect_updated_cb(struct diff_queue_struct *q,
-					 struct diff_options *options,
+					 struct diff_options *options UNUSED,
 					 void *data)
 {
 	struct wt_status *s = data;
diff --git a/xdiff/xdiffi.c b/xdiff/xdiffi.c
index 32652ded2d..344c2dfc3e 100644
--- a/xdiff/xdiffi.c
+++ b/xdiff/xdiffi.c
@@ -973,7 +973,7 @@ void xdl_free_script(xdchange_t *xscr) {
 	}
 }
 
-static int xdl_call_hunk_func(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,
+static int xdl_call_hunk_func(xdfenv_t *xe UNUSED, xdchange_t *xscr, xdemitcb_t *ecb,
 			      xdemitconf_t const *xecfg)
 {
 	xdchange_t *xch, *xche;
diff --git a/xdiff/xemit.c b/xdiff/xemit.c
index c4ccd68d47..75f0fe4986 100644
--- a/xdiff/xemit.c
+++ b/xdiff/xemit.c
@@ -95,7 +95,7 @@ xdchange_t *xdl_get_hunk(xdchange_t **xscr, xdemitconf_t const *xecfg)
 }
 
 
-static long def_ff(const char *rec, long len, char *buf, long sz, void *priv)
+static long def_ff(const char *rec, long len, char *buf, long sz)
 {
 	if (len > 0 &&
 			(isalpha((unsigned char)*rec) || /* identifier? */
@@ -117,7 +117,7 @@ static long match_func_rec(xdfile_t *xdf, xdemitconf_t const *xecfg, long ri,
 	const char *rec;
 	long len = xdl_get_rec(xdf, ri, &rec);
 	if (!xecfg->find_func)
-		return def_ff(rec, len, buf, sz, xecfg->find_func_priv);
+		return def_ff(rec, len, buf, sz);
 	return xecfg->find_func(rec, len, buf, sz, xecfg->find_func_priv);
 }