Comment by tux1968
5 years ago
I must be really missing something obvious, since I don't know why so many replies are talking about debugging.
We're talking about the speed of production code (aren't we?) that already elides a lot of debugging features. The article doesn't say that they've found a feature for faster debugging, they're saying that explicitly marking tail calls makes their production code faster... so I'm still lost why the compiler can't find these optimizations in production builds without explicit markup.
People are talking about debugging because debugging needs to be possible.
If you blow the stack in a debug build, your application fucking crashes. That makes debug builds useless and can make debugging some problems very difficult. Therefore we need a mechanism that guarantees the code doesn't blow the stack in debug builds either. "Only optimized production builds are executable" is not the path you want to go if it's avoidable.
If you don't have markup to enforce TCO in every build, some build will be broken or needs to use a different code path altogether to avoid such breakage.