* Module: improve doc comments
 * C backend: improve const-correctness
 * C backend: introduce renderTypeAndName
 * C backend: put `static` on functions when appropriate
 * C backend: fix not handling errors in genBinOp
 * C backend: handle more IR instructions
   - alloc, store, boolean comparisons, ret_ptr
 * C backend: call instruction properly stores its result
 * test harness: ensure execution tests have empty stderr