GATE CS 2024 Set 2 — Question 29

Statement (A) is true; it is the standard definition of an attribute grammar. Statement (B) is FALSE because L-attributed definitions are specifically defined such that their attributes can be evaluated in a single depth-first (left-to-right) traversal. Statement (C) is true because synthesized attributes depend only on children nodes, which are available during a bottom-up (post-order) traversal. Statement (D) is FALSE because not all L-attributed definitions can be evaluated during a single bottom-up pass; while techniques like marker non-terminals exist to handle inherited attributes, they can transform an $LR(1)$ grammar into one that is no longer $LR(1)$.