diff --git a/compat/win32/pthread.h b/compat/win32/pthread.h
index 4d204312d3..11383eb5f4 100644
--- a/compat/win32/pthread.h
+++ b/compat/win32/pthread.h
@@ -40,7 +40,7 @@ WINBASEAPI VOID WINAPI
 WakeConditionVariable(PCONDITION_VARIABLE ConditionVariable);
 WINBASEAPI VOID WINAPI
 WakeAllConditionVariable(PCONDITION_VARIABLE ConditionVariable);
-WINBASEAPI WINBOOL WINAPI
+WINBASEAPI BOOL WINAPI
 SleepConditionVariableCS(PCONDITION_VARIABLE ConditionVariable,
                          PCRITICAL_SECTION CriticalSection,
                          DWORD dwMilliseconds);