diff --git a/dir.c b/dir.c
index 71108ac79b..0a67a99cb3 100644
--- a/dir.c
+++ b/dir.c
@@ -3579,7 +3579,8 @@ static void write_one_dir(struct untracked_cache_dir *untracked,
 	struct stat_data stat_data;
 	struct strbuf *out = &wd->out;
 	unsigned char intbuf[16];
-	unsigned int intlen, value;
+	unsigned int value;
+	uint8_t intlen;
 	int i = wd->index++;
 
 	/*
@@ -3632,7 +3633,7 @@ void write_untracked_extension(struct strbuf *out, struct untracked_cache *untra
 	struct ondisk_untracked_cache *ouc;
 	struct write_data wd;
 	unsigned char varbuf[16];
-	int varint_len;
+	uint8_t varint_len;
 	const unsigned hashsz = the_hash_algo->rawsz;
 
 	CALLOC_ARRAY(ouc, 1);
@@ -3738,7 +3739,7 @@ static int read_one_dir(struct untracked_cache_dir **untracked_,
 	struct untracked_cache_dir ud, *untracked;
 	const unsigned char *data = rd->data, *end = rd->end;
 	const unsigned char *eos;
-	unsigned int value;
+	uint64_t value;
 	int i;
 
 	memset(&ud, 0, sizeof(ud));
@@ -3830,7 +3831,8 @@ struct untracked_cache *read_untracked_extension(const void *data, unsigned long
 	struct read_data rd;
 	const unsigned char *next = data, *end = (const unsigned char *)data + sz;
 	const char *ident;
-	int ident_len;
+	uint64_t ident_len;
+	uint64_t varint_len;
 	ssize_t len;
 	const char *exclude_per_dir;
 	const unsigned hashsz = the_hash_algo->rawsz;
@@ -3867,8 +3869,8 @@ struct untracked_cache *read_untracked_extension(const void *data, unsigned long
 	if (next >= end)
 		goto done2;
 
-	len = decode_varint(&next);
-	if (next > end || len == 0)
+	varint_len = decode_varint(&next);
+	if (next > end || varint_len == 0)
 		goto done2;
 
 	rd.valid      = ewah_new();
@@ -3877,9 +3879,9 @@ struct untracked_cache *read_untracked_extension(const void *data, unsigned long
 	rd.data	      = next;
 	rd.end	      = end;
 	rd.index      = 0;
-	ALLOC_ARRAY(rd.ucd, len);
+	ALLOC_ARRAY(rd.ucd, varint_len);
 
-	if (read_one_dir(&uc->root, &rd) || rd.index != len)
+	if (read_one_dir(&uc->root, &rd) || rd.index != varint_len)
 		goto done;
 
 	next = rd.data;
diff --git a/read-cache.c b/read-cache.c
index 06ad74db22..41b44148b1 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -1807,7 +1807,7 @@ static struct cache_entry *create_from_disk(struct mem_pool *ce_mem_pool,
 
 	if (expand_name_field) {
 		const unsigned char *cp = (const unsigned char *)name;
-		size_t strip_len, previous_len;
+		uint64_t strip_len, previous_len;
 
 		/* If we're at the beginning of a block, ignore the previous name */
 		strip_len = decode_varint(&cp);
@@ -2655,8 +2655,10 @@ static int ce_write_entry(struct hashfile *f, struct cache_entry *ce,
 		hashwrite(f, ce->name, len);
 		hashwrite(f, padding, align_padding_size(size, len));
 	} else {
-		int common, to_remove, prefix_size;
+		int common, to_remove;
+		uint8_t prefix_size;
 		unsigned char to_remove_vi[16];
+
 		for (common = 0;
 		     (common < previous_name->len &&
 		      ce->name[common] &&
diff --git a/varint.c b/varint.c
index 409c4977a1..03cd54416b 100644
--- a/varint.c
+++ b/varint.c
@@ -1,11 +1,11 @@
 #include "git-compat-util.h"
 #include "varint.h"
 
-uintmax_t decode_varint(const unsigned char **bufp)
+uint64_t decode_varint(const unsigned char **bufp)
 {
 	const unsigned char *buf = *bufp;
 	unsigned char c = *buf++;
-	uintmax_t val = c & 127;
+	uint64_t val = c & 127;
 	while (c & 128) {
 		val += 1;
 		if (!val || MSB(val, 7))
@@ -17,7 +17,7 @@ uintmax_t decode_varint(const unsigned char **bufp)
 	return val;
 }
 
-int encode_varint(uintmax_t value, unsigned char *buf)
+uint8_t encode_varint(uint64_t value, unsigned char *buf)
 {
 	unsigned char varint[16];
 	unsigned pos = sizeof(varint) - 1;
diff --git a/varint.h b/varint.h
index f78bb0ca52..eb401935bd 100644
--- a/varint.h
+++ b/varint.h
@@ -1,7 +1,7 @@
 #ifndef VARINT_H
 #define VARINT_H
 
-int encode_varint(uintmax_t, unsigned char *);
-uintmax_t decode_varint(const unsigned char **);
+uint8_t encode_varint(uint64_t, unsigned char *);
+uint64_t decode_varint(const unsigned char **);
 
 #endif /* VARINT_H */