Early C++ implementations used setjmp/longjmp to support exceptions, and then each try block would lead to settting the setjmp context. So there definitely was a runtime overhead, even with no exceptions thrown.
I don't think it's very popular today. Modern implementation don't use this anymore and do not incur run-time overhead when no exception are thrown. However, they do incur some space overhead: the implementation need to maintain pretty large tables to know what needs to be unwound (which destructors to call, in which order) when an exception is thrown. In most environment this space overhead shouldn't be a problem (PC, server). But for embedded development it may be a problem. And then disabling exception to save space brings back the issues with error checking (or the lack of it...).
For more details, search for C++ exception implementation and you should find all the info you need. Or look into G++ documentation for example, this topic is covered somewhere.
I don't think it's very popular today. Modern implementation don't use this anymore and do not incur run-time overhead when no exception are thrown. However, they do incur some space overhead: the implementation need to maintain pretty large tables to know what needs to be unwound (which destructors to call, in which order) when an exception is thrown. In most environment this space overhead shouldn't be a problem (PC, server). But for embedded development it may be a problem. And then disabling exception to save space brings back the issues with error checking (or the lack of it...).
For more details, search for C++ exception implementation and you should find all the info you need. Or look into G++ documentation for example, this topic is covered somewhere.