[LevelAd8]

2 more instructions in GodBolt for the second version, in the end the urge to look cool and "elite" more often than not causes trouble. Unless there really is a need for complexity, it's almost always better to follow KISS principle

[nkurz]

I saw no difference for between unwind's two versions with current GCC, clang, or icc with -O3: https://godbolt.org/z/n6avo5ovq. Did you possibly forgot to use optimization? I was surprised though to see that icc inlined the call to strlen!

[unwind]

Okay, thanks.

Obviously using post-decrement in the if like I did is a red flag of readability/complexity in many cases, and I could just have well kept the subtraction to the indexing line.