If you use error codes, you always pay the cost (even cheap) of generating codes. If the function isn’t online able this might increase the stack usage, prevent

If you use error codes, you always pay the cost (even cheap) of generating codes. If the function isn’t online able this might increase the stack usage, prevent inlining in the first place, etc. With exceptions the error paths don’t even have to exist in your hot code. The cost of exceptions when they aren’t thrown has come a long way since 2011 (the time of that post) in clang and gcc and I’m 99% sure is almost always zero now.