Then maybe I did not express myself in the best terms. QBE definitely supports stack slots and their registerization! Minic, a small C frontend shipped with QBE makes use of them.<p>The difference is that LLVM forces you to use them even when you know your locals do <i>not</i> escape (i.e. your source language is Pascal), QBE doesn&#x27;t.<p>So, LLVM makes you use stack slots for two independent problems: 1. Compiling languages like C where locals can escape, and 2. Avoiding to construct SSA form in the frontend.  In QBE, you use stack slots (alloc4, alloc8) to solve 1, but to solve 2, you can simply emit non-ssa form and QBE will fixup things for you.