SDD for Simple Type Declarations

The SDD in Fig. 5.8 is used for declarations of the form:

T id1, id2, id3;
Where:

• T is a type (int or float)
• Followed by a comma-separated list of identifiers

Explanation:

• T.type is a synthesized attribute that carries the type (int or float)
• L.inh is an inherited attribute passed from the type T to all identifiers in the list L
• The addType() function is used to store the type info of each identifier in the symbol table.

Example: int id1, id2, id3;

Parsing this using the productions:

D → T L
T → int → T.type = integer
L → L1 , id3
L1 → L2 , id2
L2 → id1

Here, L.inh = integer, and each addType(id.entry, L.inh) assigns the type integer to id1, id2, and id3.

Dependency Graph for int id1, id2, id3

Graph Nodes Explained:

The type is propagated downward through L.inh attributes
Each addType() operation depends on both the identifier and the type value.