The irony here is that the CPU will set the underflow making this trivial to detect in ASM with the `jb` instruction. The equivalent C++ would be something like

The irony here is that the CPU will set the underflow making this trivial to detect in ASM with the `jb` instruction. The equivalent C++ would be something like: if (new_len > child.length()) As stated in the article, checking if an unsigned is less than 0 is a silly logic error but obviously one that is understandable to make. Still it's the sort of thing you'd expect automated tools would be able to catch.