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The linked image has formatting as intended originally. These are exposing so many different ways things look wrong without an official code markup tag.

The programming world at large has cast goto statements as always bad, but attempting to protect bad programmers from themselves is a cause so lost that it has six seasons and a 12-minute epilogue. Seeing someone write messy code and taking away everyone's goto is like seeing a nigger waving a handgun around and taking away everyone's handgun, failing to identify the problem either way. We don't need common sense goto control.

All programming constructs and mechanisms can be abused, such that singling out goto is pointless. Using goto can be perfectly appropriate and perfectly elegant. C/C++ has at least one case where goto appears absent a better mechanism, but I'll also show some situations where it's as well to use it.

Suppose we iterate pairs of integers i then j, but sometimes want to skip to the next i, ignoring any remaining j and any operations after the j-loop. One way to do this by jumping out and over said operations by placing a label at the end of the i-loop:


This is for lack of labelled break and continue, which has been suggested many times and looks like it could actually be in the next C++ release. Until then, the official C solution is goto, and it is perfectly clear and performant. It is not better to screw around with a flag when you can just jump the flow. Making a separate inner function and returning early can be appropriate though, if it is not too arduous to pass in any local variables needed.

For a different scenario where goto is perfect, suppose we have a system state update function which must consume all the time given to it. Action functions modify the remaining time and return true if they concluded early, potentially having changed the state:


The goto-avoiding way could be a while loop and incurring an extra test whether any time remains. Probably worse than that is calling itself recursively just for re-entry with a lower amount of time. If the logic is in the position of knowing it needs to consume remaining time, just jump to the top!

Also in the context of state systems, there is nothing wrong with having multiple possible conclusions at the end of a function and a way to jump to the alternative flow, which becomes useful when multiple logic branches use it. Loosely:


As with any mechanism, sensible use of it and sensibly-named labels are what makes it pass the readability test. Naming a label "hell" is also funny, everyone should get to do that at least once.