I just caught by this again. We added an override for FORMAT_DOUBLE, to apply some fixes to it, but the compiler is still using the buggy version from the precompiled base library. I had no idea why this was happening. Luckily I thought of searching through my problem reports for the word "override", and I found this issue which of course explained why I was having the problem.

This is a very easy trap to fall into. The mistake is only noticed when testing. I think that a compile-time error is essential for this.