diff --git a/cache.h b/cache.h
index 1e4b4f06e1..cbe1935ba6 100644
--- a/cache.h
+++ b/cache.h
@@ -826,7 +826,6 @@ int normalize_path_copy(char *dst, const char *src);
 int longest_ancestor_length(const char *path, struct string_list *prefixes);
 char *strip_path_suffix(const char *path, const char *suffix);
 int daemon_avoid_alias(const char *path);
-int offset_1st_component(const char *path);
 
 /* object replacement */
 #define LOOKUP_REPLACE_OBJECT 1
diff --git a/compat/mingw.c b/compat/mingw.c
index e9892f8ee4..a0e13bc862 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -1823,3 +1823,27 @@ pid_t waitpid(pid_t pid, int *status, int options)
 	errno = EINVAL;
 	return -1;
 }
+
+int mingw_offset_1st_component(const char *path)
+{
+	int offset = 0;
+	if (has_dos_drive_prefix(path))
+		offset = 2;
+
+	/* unc paths */
+	else if (is_dir_sep(path[0]) && is_dir_sep(path[1])) {
+
+		/* skip server name */
+		char *pos = strpbrk(path + 2, "\\/");
+		if (!pos)
+			return 0; /* Error: malformed unc path */
+
+		do {
+			pos++;
+		} while (*pos && !is_dir_sep(*pos));
+
+		offset = pos - path;
+	}
+
+	return offset + is_dir_sep(path[offset]);
+}
diff --git a/compat/mingw.h b/compat/mingw.h
index e033e720c9..3eaf822e28 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -339,6 +339,8 @@ static inline char *mingw_find_last_dir_sep(const char *path)
 	return ret;
 }
 #define find_last_dir_sep mingw_find_last_dir_sep
+int mingw_offset_1st_component(const char *path);
+#define offset_1st_component mingw_offset_1st_component
 #define PATH_SEP ';'
 #define PRIuMAX "I64u"
 #define PRId64 "I64d"
diff --git a/git-compat-util.h b/git-compat-util.h
index 7849d31405..b6f03b36dc 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -267,6 +267,10 @@ extern char *gitbasename(char *);
 #define has_dos_drive_prefix(path) 0
 #endif
 
+#ifndef offset_1st_component
+#define offset_1st_component(path) (is_dir_sep((path)[0]))
+#endif
+
 #ifndef is_dir_sep
 #define is_dir_sep(c) ((c) == '/')
 #endif
diff --git a/path.c b/path.c
index f9c5062427..bc804a31b3 100644
--- a/path.c
+++ b/path.c
@@ -823,10 +823,3 @@ int daemon_avoid_alias(const char *p)
 		}
 	}
 }
-
-int offset_1st_component(const char *path)
-{
-	if (has_dos_drive_prefix(path))
-		return 2 + is_dir_sep(path[2]);
-	return is_dir_sep(path[0]);
-}