> And my problem was that this test would be running on a bazillion machines if upstreamed, for about 0.000000001% chance of ever be executed, bar for our own l

> And my problem was that this test would be running on a bazillion machines if upstreamed, for about 0.000000001% chance of ever be executed, bar for our own low volume, industrial SoC. We'd add cycles to a critical code path for zero reason, and without conditional compile, nobody would know by reading the code. That's a good reason why C++ is generally superior to C in embedded development: with C++, you can get at the same time compiler checks for the validity of your whole code to prevent bitrot (unlike macros), and ensure that the actual implementations will only have the actual code that is relevant to them - e.g. set your flags as constexpr variables in your device's struct, and have the tests run under `if constexpr` conditions. Devices without the flag set won't have the check compiled in, and others will. But oh well :)