diff --git a/cache.h b/cache.h
index d0494c8533..7bd78ca282 100644
--- a/cache.h
+++ b/cache.h
@@ -1203,6 +1203,11 @@ struct object_context {
 #define GET_SHA1_FOLLOW_SYMLINKS 0100
 #define GET_SHA1_ONLY_TO_DIE    04000
 
+#define GET_SHA1_DISAMBIGUATORS \
+	(GET_SHA1_COMMIT | GET_SHA1_COMMITTISH | \
+	GET_SHA1_TREE | GET_SHA1_TREEISH | \
+	GET_SHA1_BLOB)
+
 extern int get_sha1(const char *str, unsigned char *sha1);
 extern int get_sha1_commit(const char *str, unsigned char *sha1);
 extern int get_sha1_committish(const char *str, unsigned char *sha1);
diff --git a/sha1_name.c b/sha1_name.c
index faf873cf7f..0ff83a9985 100644
--- a/sha1_name.c
+++ b/sha1_name.c
@@ -327,6 +327,10 @@ static int get_short_sha1(const char *name, int len, unsigned char *sha1,
 	prepare_alt_odb();
 
 	memset(&ds, 0, sizeof(ds));
+
+	if (HAS_MULTI_BITS(flags & GET_SHA1_DISAMBIGUATORS))
+		die("BUG: multiple get_short_sha1 disambiguator flags");
+
 	if (flags & GET_SHA1_COMMIT)
 		ds.fn = disambiguate_commit_only;
 	else if (flags & GET_SHA1_COMMITTISH)