In the mid 2000s, using exceptions in C++ affected performance negatively, even if they weren't thrown. Performance-critical code was often written using error code return values to indicate exceptions. Bloating the code base with returning error codes and error code handling was simply the only way of writing performance-critical and exception-safe code.
In modern C++ compilers, exceptions only affect the performance when thrown. Considering all the thrown exceptions are rare enough to quit the current process, we can safely use exceptions even in performance-critical systems and benefit from all the advantages of using exceptions instead of error codes.
