diff --git a/dlls/ntoskrnl.exe/tests/utils.h b/dlls/ntoskrnl.exe/tests/utils.h
index 98fe3f97864..fc675e17dd0 100644
--- a/dlls/ntoskrnl.exe/tests/utils.h
+++ b/dlls/ntoskrnl.exe/tests/utils.h
@@ -110,7 +110,7 @@ static inline void winetest_set_location( const char* file, int line )
     data->current_line=line;
 }
 
-static inline void kvprintf(const char *format, __ms_va_list ap)
+static inline void kvprintf(const char *format, va_list ap)
 {
     struct tls_data *data = get_tls_data();
     IO_STATUS_BLOCK io;
@@ -121,23 +121,23 @@ static inline void kvprintf(const char *format, __ms_va_list ap)
 static inline void WINAPIV kprintf(const char *format, ...) __WINE_PRINTF_ATTR(1,2);
 static inline void WINAPIV kprintf(const char *format, ...)
 {
-    __ms_va_list valist;
+    va_list valist;
 
-    __ms_va_start(valist, format);
+    va_start(valist, format);
     kvprintf(format, valist);
-    __ms_va_end(valist);
+    va_end(valist);
 }
 
 static inline void WINAPIV winetest_printf( const char *msg, ... ) __WINE_PRINTF_ATTR(1,2);
 static inline void WINAPIV winetest_printf( const char *msg, ... )
 {
     struct tls_data *data = get_tls_data();
-    __ms_va_list valist;
+    va_list valist;
 
     kprintf( "%s:%d: ", data->current_file, data->current_line );
-    __ms_va_start( valist, msg );
+    va_start( valist, msg );
     kvprintf( msg, valist );
-    __ms_va_end( valist );
+    va_end( valist );
 }
 
 static inline NTSTATUS winetest_init(void)
@@ -244,7 +244,7 @@ static inline LONG winetest_add_line( void )
     return count;
 }
 
-static inline int winetest_vok( int condition, const char *msg, __ms_va_list args )
+static inline int winetest_vok( int condition, const char *msg, va_list args )
 {
     struct tls_data *data = get_tls_data();
 
@@ -296,13 +296,13 @@ static inline int winetest_vok( int condition, const char *msg, __ms_va_list arg
 static inline void WINAPIV winetest_ok( int condition, const char *msg, ... ) __WINE_PRINTF_ATTR(2,3);
 static inline void WINAPIV winetest_ok( int condition, const char *msg, ... )
 {
-    __ms_va_list args;
-    __ms_va_start(args, msg);
+    va_list args;
+    va_start(args, msg);
     winetest_vok(condition, msg, args);
-    __ms_va_end(args);
+    va_end(args);
 }
 
-static inline void winetest_vskip( const char *msg, __ms_va_list args )
+static inline void winetest_vskip( const char *msg, va_list args )
 {
     if (winetest_add_line() < winetest_mute_threshold)
     {
@@ -317,37 +317,37 @@ static inline void winetest_vskip( const char *msg, __ms_va_list args )
 static inline void WINAPIV winetest_skip( const char *msg, ... ) __WINE_PRINTF_ATTR(1,2);
 static inline void WINAPIV winetest_skip( const char *msg, ... )
 {
-    __ms_va_list args;
-    __ms_va_start(args, msg);
+    va_list args;
+    va_start(args, msg);
     winetest_vskip(msg, args);
-    __ms_va_end(args);
+    va_end(args);
 }
 
 static inline void WINAPIV winetest_win_skip( const char *msg, ... ) __WINE_PRINTF_ATTR(1,2);
 static inline void WINAPIV winetest_win_skip( const char *msg, ... )
 {
-    __ms_va_list args;
-    __ms_va_start(args, msg);
+    va_list args;
+    va_start(args, msg);
     if (!running_under_wine)
         winetest_vskip(msg, args);
     else
         winetest_vok(0, msg, args);
-    __ms_va_end(args);
+    va_end(args);
 }
 
 static inline void WINAPIV winetest_trace( const char *msg, ... ) __WINE_PRINTF_ATTR(1,2);
 static inline void WINAPIV winetest_trace( const char *msg, ... )
 {
-    __ms_va_list args;
+    va_list args;
 
     if (!winetest_debug)
         return;
     if (winetest_add_line() < winetest_mute_threshold)
     {
         winetest_print_context( "" );
-        __ms_va_start(args, msg);
+        va_start(args, msg);
         kvprintf( msg, args );
-        __ms_va_end(args);
+        va_end(args);
     }
     else
         InterlockedIncrement(&muted_traces);
@@ -378,13 +378,13 @@ static inline void WINAPIV winetest_push_context( const char *fmt, ... ) __WINE_
 static inline void WINAPIV winetest_push_context( const char *fmt, ... )
 {
     struct tls_data *data = get_tls_data();
-    __ms_va_list valist;
+    va_list valist;
 
     if (data->context_count < ARRAY_SIZE(data->context))
     {
-        __ms_va_start(valist, fmt);
+        va_start(valist, fmt);
         vsnprintf( data->context[data->context_count], sizeof(data->context[data->context_count]), fmt, valist );
-        __ms_va_end(valist);
+        va_end(valist);
         data->context[data->context_count][sizeof(data->context[data->context_count]) - 1] = 0;
     }
     ++data->context_count;