diff --git a/cache.h b/cache.h
index 33decd942d..222d9cf3a7 100644
--- a/cache.h
+++ b/cache.h
@@ -1117,6 +1117,7 @@ const char *split_cmdline_strerror(int cmdline_errno);
 /* git.c */
 struct startup_info {
 	int have_repository;
+	const char *prefix;
 };
 extern struct startup_info *startup_info;
 
diff --git a/setup.c b/setup.c
index a3b76de2bb..833db12bc4 100644
--- a/setup.c
+++ b/setup.c
@@ -512,8 +512,10 @@ const char *setup_git_directory_gently(int *nongit_ok)
 	const char *prefix;
 
 	prefix = setup_git_directory_gently_1(nongit_ok);
-	if (startup_info)
+	if (startup_info) {
 		startup_info->have_repository = !nongit_ok || !*nongit_ok;
+		startup_info->prefix = prefix;
+	}
 	return prefix;
 }