Appreciate the answers and tips (though I checked some of your suggestions already). In our case, it's third-party software partially generating C code with les

Appreciate the answers and tips (though I checked some of your suggestions already). In our case, it's third-party software partially generating C code with less-than-ideal test coverage and it's a huge time sink to fix. It's been a while, but as I recall, gcc 4.9 would compile ok, only the generated executable would crash, and would also generate double-frees with glibc and stuff (with one-shot command-line programs not app servers, so this isn't as scary as it sounds). This after heavy modifications on my part to get it even running. Note our own code, OTOH, has almost 100% coverage, and I'm considering replacing the old third-party libs/tools for the next release. However, this is a huge time sink when the code works just fine otherwise, and in any case needs to be maintained, so I'm looking for a canned gcc installation (maybe a Docker image or self-compiled gcc chain which I used to use a couple years ago, but stopped bootstrapping on eg newer Ubuntu hosts by now). As build servers so far, I'm using older distros (CentOS 6, Debian 8.6) with native gcc 4.7 or gcc 4.7 packages on newer distros with success, and also an old Mac OS box with gcc 4.7 installed from MacPorts at a time when it wasn't yet broken. My intent wasn't to criticize gcc, but I think 7 years is not that long of a life-time for non-trivial software.