Merge branch 'v0.20.x'

src/LogBackend.cxx

@@ -164,7 +164,7 @@ FileLog(const Domain &domain, const char *message) noexcept
 		domain.GetName(),
 		chomp_length(message), message);
 
-#ifdef WIN32
+#ifdef _WIN32
 	/* force-flush the log file, because setvbuf() does not seem
 	   to have an effect on WIN32 */
 	fflush(stderr);