Keep running the program after SIGABRT c++ signal

Question

I use a third library in my c++ program which under certain circumstances emits SIGABRT signal. I know that trying to free non-initialized pointer or something like this can be the cause of this signal. Nevertheless I want to keep running my program after this signal is emitted, to show a message and allow the user to change the settings, in order to cope with this signal.
(I use QT for developing.)

How can I do that?

Answer 1

I use a third library in my c++ program which under certain circumstances emits SIGABRT signal

If you have the source code of that library, you need to correct the bug (and the bug could be in your code).

BTW, probably SIGABRT happens because abort(3) gets indirectly called (perhaps because you violated some conventions or invariants of that library, which might use assert(3) - and indirectly call abort). I guess that in caffe the various CHECK* macros could indirectly call abort. I leave you to investigate that.

If you don't have the source code or don't have the capacity or time to fix that bug in that third party library, you should give up using that library and use something else.

In many cases, you should trust external libraries more than your own code. Probably, you are abusing or misusing that library. Read carefully its documentation and be sure that your own code calling it is using that library correctly and respects its invariants and conventions. Probably the bug is in your own code, at some other place.

I want to keep running my program

This is impossible (or very unreliable, so unreasonable). I guess that your program has some undefined behavior. Be very scared, and work hard to avoid UB.

You need to improve your debugging skills. Learn better how to use the gdb debugger, valgrind, GCC sanitizers (e.g. instrumentation options like -fsanitize=address, -fsanitize=undefined and others), etc...

You reasonably should not try to handle SIGABRT even if in principle you might (but then read carefully signal(7), signal-safety(7) and hints about handling Unix signals in Qt). I strongly recommend to avoid even trying catching SIGABRT.