Hrmm. Surely the vast majority of testing happens on non-release builds, despite the fact that release builds may also be tested. Unit tests are generally fastbuild artifacts that are linked with many objects that are not in the release, including the test's main function and the test cases themselves. Integration tests and end-to-end tests often run with NDEBUG undefined and with things like sanitizers and checked allocators. I would say that hardly anyone runs unit tests on release build artifacts just because it takes forever to produce them.
When I was at Google we ran most tests both with production optimizations and without. There is no reason not to do it since the cost of debugging those problems is huge.
> Surely the vast majority of testing happens on non-release builds, despite the fact that release builds may also be tested.
Of course.
> I would say that hardly anyone runs unit tests on release build artifacts just because it takes forever to produce them.
I don't know that this follows: just because 99% of the invocations of your unit test are in fastbuild doesn't mean that you don't also test everything in opt at least once.
I can't remember seeing any cc_test target at Google that ran with realistic release optimizations (AutoFDO/SamplePGO+LTO) and even if they did it's still not the release binary because it links in the test case and the test main function.
Did you look in the CI system for configurations there? I see FDO enabled in those tests. (Speaking at a high level, configurations can be modified in bazelrc and with flags without being explicitly listed in the cc_test rule itself)
> release binary because it links in the test case and the test main function.
Sure, but it's verifiably the same object files as get put into the release artifact.
