Generation and processing of exceptions using integer types is a bad practice of C++ programming. You should use more informative types for these purposes, for example types derived from the class std::exception. But sometimes you have to deal with a low-quality code like this:
char *ptr1; char *ptr2; try { try { throw ptr2 - ptr1; } catch (int) { std::cout << "catch 1: on x86" << std::endl; } } catch (ptrdiff_t) { std::cout << "catch 2: on x64" << std::endl; }
You should be very attentive and avoid generation or processing of exceptions using memsize-types because it may result in changes of program logic. To correct this code you may replace “catch (int)” with “catch (ptrdiff_t)”. A more correct way is to use a special class to pass the information about an error that has occurred.
Diagnostic
We have not encountered errors of this type in practice yet but the tool PVS-Studio can detect them. The diagnostic message V115 will be shown when an exception is generated with the help of a memsize-type, while the warning V116 will be generated when a memsize-type is used in catch operator.