The only real downside is that it slows things down quite a bit (30s vs 12s for a full test run in my current project; I've seen both better and worse ratios in

The only real downside is that it slows things down quite a bit (30s vs 12s for a full test run in my current project; I've seen both better and worse ratios in other projects). I've also seen a project that made heavy use of generated code and a race-enabled build would choke on the very large source files. But overall I agree that it seems worthwhile to make -race the default.