diff --git a/platform/cert.c b/platform/cert.c
index 82fa5a7..4779359 100644
--- a/platform/cert.c
+++ b/platform/cert.c
@@ -249,7 +249,8 @@ HCERTSTORE WINAPI hook_CertOpenStore(
     return next_CertOpenStore(lpszStoreProvider, dwEncodingType, hCryptProv, dwFlags, pvPara);*/
 
 }
-WINHTTPAPI BOOL hook_WinHttpSetOption(
+
+static BOOL hook_WinHttpSetOption(
     HINTERNET hInternet,
     DWORD     dwOption,
     LPVOID    lpBuffer,