"the processes that have been mandated for safety-related projects since year dot."
Are you thinking of a particular industry, or standard (or set of standards)?
The industry I'm most familiar with (starting in pre-history days with DEF STD 00-55) currently considers DO178 and DO254 and friends to be at the heart of its design/code/test processes.
They're not bad, as processes go, but when I last looked in detail a couple of years back there seemed to be a move to de-emphasise the detail at the back end of these processes because they were "over engineered" (ie costing the company concerned too much money, taking too long before stuff could be shipped).
The management in question didn't seem to have any real documented justification for doing so, or for doing various other things which diminished the trustworthiness of the end product (e.g. testing a *model* of the desired system's behaviour, rather than the executable code itself as produced by the relevant toolchain. This led to the idea that a change from one processor to another radically different one (e.g. MIPS to Motorola or vice versa) didn't require any additional testing to test for target-dependent errors in the toolchains.
There may be trouble ahead...