Is there an entity behind the code / package / library that you are using that you can hold Liable in case of ill-behaviour.
Don‘t use gcc for mission critical stuff.
Use a compiler that is backed by people who are responsible for the compilers behaviour by contract. Greenhills / Hightec Alliums Tasking Compiler. The list goes on and on.
As for chips: cooperate with the manufacturer. Specific your requirements for the chips behaviour. Get it manufactured. If it is available off the shelf and matches your spec, go on and buy off the shelf but TEST if it actually behaves like stated on the sales PowerPoint slide. If not report back to the manufacturer and get it fixed.