diff --git a/programs/taskkill/taskkill.c b/programs/taskkill/taskkill.c
index 193ed058297..6704b121aa9 100644
--- a/programs/taskkill/taskkill.c
+++ b/programs/taskkill/taskkill.c
@@ -39,7 +39,7 @@ struct pid_close_info
     BOOL found;
 };
 
-static int taskkill_vprintfW(const WCHAR *msg, __ms_va_list va_args)
+static int taskkill_vprintfW(const WCHAR *msg, va_list va_args)
 {
     int wlen;
     DWORD count, ret;
@@ -75,27 +75,27 @@ static int taskkill_vprintfW(const WCHAR *msg, __ms_va_list va_args)
 
 static int WINAPIV taskkill_printfW(const WCHAR *msg, ...)
 {
-    __ms_va_list va_args;
+    va_list va_args;
     int len;
 
-    __ms_va_start(va_args, msg);
+    va_start(va_args, msg);
     len = taskkill_vprintfW(msg, va_args);
-    __ms_va_end(va_args);
+    va_end(va_args);
 
     return len;
 }
 
 static int WINAPIV taskkill_message_printfW(int msg, ...)
 {
-    __ms_va_list va_args;
+    va_list va_args;
     WCHAR msg_buffer[8192];
     int len;
 
     LoadStringW(GetModuleHandleW(NULL), msg, msg_buffer, ARRAY_SIZE(msg_buffer));
 
-    __ms_va_start(va_args, msg);
+    va_start(va_args, msg);
     len = taskkill_vprintfW(msg_buffer, va_args);
-    __ms_va_end(va_args);
+    va_end(va_args);
 
     return len;
 }