Kernel drivers and embedded system bare metal firmware.
The problem with C is that in any bigger project something always slips through even the best programmers, reviewers, static analysis and unit tests. And that something can lead to disastrous crashes and security vulnerabilities.
That said, sometimes I'm shocked what kind of disasters get past the analyzers.
Stakes are higher than ever. It's not just about functional correctness and avoiding crashes anymore. Your code needs to be secure against outside world malicious actions. Getting rid of counterintuitive security vulnerabilities is very, very hard.
Sadly we are a very very tiny percentage, as proven by Herb Sutter question to the audience at CppCon (1% of the audience answered positively), and CVE frequent updates.
https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=memory+corr...
You can still overwrite memory but it suddenly became much less likely.
Yeah, bare metal systems often don't allocate at all. Although one sin they often do commit is using same buffer for multiple purposes. What could go wrong...
Perhaps even more common is allocating a buffer on stack and writing past bounds somehow. Also DMA to/from stack is usually not a great idea...
Above things sound dumb, but can easily happen when you build your abstraction layers and use them carelessly.
wait what oh my god
Just imagine how many millions the IT industry and PhD research have spent developing solutions that would improve C's safety, many of them largely ignored by most C developers.
That's also true of all the other languages.
Of course you can shoot yourself into foot with stuff like metatables in Lua and Python metaclasses and whatnot. Then again you should see some C macro messes around...
Anyways I don't like when people defend C with that age old argument it requires a clever disciplined programmer that never makes mistakes. Because either such programmers don't exist or they're very rare.
Fewer defects, or just different (arguably less severe) defects? It's great that you're sure, but evidence would be even better.
Scripting languages do have their pitfalls. Lua and python can have type mismatches and even typos causing misbehavior, things that usually aren't issues with C.
However, you do need significantly less code than in C.
C and C++ = Logic Errors + Memory Corruption + UB
From this point of view,
Σ Logic Errors < Σ (Logic Errors + Memory Corruption + UB)