diff --git a/desktop_version/src/FileSystemUtils.cpp b/desktop_version/src/FileSystemUtils.cpp
index f9169b40..2ae0f06c 100644
--- a/desktop_version/src/FileSystemUtils.cpp
+++ b/desktop_version/src/FileSystemUtils.cpp
@@ -164,7 +164,7 @@ char *FILESYSTEM_getUserLevelDirectory(void)
 	return levelDir;
 }
 
-bool FILESYSTEM_directoryExists(const char *fname)
+static bool FILESYSTEM_directoryExists(const char *fname)
 {
 	return PHYSFS_exists(fname);
 }
diff --git a/desktop_version/src/FileSystemUtils.h b/desktop_version/src/FileSystemUtils.h
index 8e59b7f2..ff306641 100644
--- a/desktop_version/src/FileSystemUtils.h
+++ b/desktop_version/src/FileSystemUtils.h
@@ -12,7 +12,6 @@ void FILESYSTEM_deinit(void);
 char *FILESYSTEM_getUserSaveDirectory(void);
 char *FILESYSTEM_getUserLevelDirectory(void);
 
-bool FILESYSTEM_directoryExists(const char *fname);
 void FILESYSTEM_mount(const char *fname);
 extern bool FILESYSTEM_assetsmounted;
 void FILESYSTEM_mountassets(const char *path);