Consider the following two syntax-directed definitions for type declarations. | SDD1: Grammar (G 1 ) | Semantic rules | | --- | --- | | (D to TV ) | (D. ma

Question

Consider the following two syntax-directed definitions for type declarations.

| SDD1: Grammar $G_1$ | Semantic rules |
| --- | --- |
| $D \to TV$ | $D.\mathrm{type}=T.\mathrm{type};\; V.\mathrm{type}=T.\mathrm{type}$ |
| $T \to int$ | $T.\mathrm{type}=int$ |
| $T \to float$ | $T.\mathrm{type}=float$ |
| $V \to V_1\,id$ | $V_1.\mathrm{type}=V.\mathrm{type};\; \operatorname{put}(id.\mathrm{entry},V.\mathrm{type})$ |
| $V \to id$ | $\operatorname{put}(id.\mathrm{entry},V.\mathrm{type})$ |

| SDD2: Grammar $G_2$ | Semantic rules |
| --- | --- |
| $D \to D_1\,id$ | $D.\mathrm{type}=D_1.\mathrm{type};\; \operatorname{put}(id.\mathrm{entry},D_1.\mathrm{type})$ |
| $D \to T\,id$ | $D.\mathrm{type}=T.\mathrm{type};\; \operatorname{put}(id.\mathrm{entry},T.\mathrm{type})$ |
| $T \to int$ | $T.\mathrm{type}=int$ |
| $T \to float$ | $T.\mathrm{type}=float$ |

$D$ is the start symbol; $int$, $float$, and $id$ are terminals. $V_1$ denotes $V$, and $D_1$ denotes $D$; subscripts distinguish the corresponding grammar symbols on opposite sides of a production. The function $\operatorname{put}$ records an identifier's type in the symbol table.

Let $P$ and $Q$ be the languages specified by grammars $G_1$ and $G_2$, respectively. Which of the following statements is/are true?

Accepted Answer

A. The languages P and Q are the same; B. SDD2 is S-attributed and contains only synthesized attributes; D. The specifications of SDD1 and SDD2 are such that the same entries get added to the symbol table

SDD1: Grammar \(G_1\)	Semantic rules
\(D \to TV\)	\(D.\mathrm{type}=T.\mathrm{type};\; V.\mathrm{type}=T.\mathrm{type}\)
\(T \to int\)	\(T.\mathrm{type}=int\)
\(T \to float\)	\(T.\mathrm{type}=float\)
\(V \to V_1\,id\)	\(V_1.\mathrm{type}=V.\mathrm{type};\; \operatorname{put}(id.\mathrm{entry},V.\mathrm{type})\)
\(V \to id\)	\(\operatorname{put}(id.\mathrm{entry},V.\mathrm{type})\)

SDD2: Grammar \(G_2\)	Semantic rules
\(D \to D_1\,id\)	\(D.\mathrm{type}=D_1.\mathrm{type};\; \operatorname{put}(id.\mathrm{entry},D_1.\mathrm{type})\)
\(D \to T\,id\)	\(D.\mathrm{type}=T.\mathrm{type};\; \operatorname{put}(id.\mathrm{entry},T.\mathrm{type})\)
\(T \to int\)	\(T.\mathrm{type}=int\)
\(T \to float\)	\(T.\mathrm{type}=float\)

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