GATE CS Lexical Analysis questions

Consider the following C statements: char *str1 = "Hello; /* Statement S1 */ char *str2 = "Hello;"; /* Statement S2 */ int *str3 = "Hello"; /* Statement S3 */ Which of the following options is/are correct?

A lexical analyzer uses the following token definitions ${letter → [A-Za-z]}$ ${digit → [0-9]}$ ${id → letter (letter | digit)^*}$ ${number → digit}$ ${ }^{+}$ ${ws → (blank | tab| newline)}$ ${ }^{+}$ For the string given below, …

Which ONE of the following statements is FALSE regarding the symbol table?

​​​Consider the following two sets: …

Consider the following statements regarding the front-end and back-end of a compiler. S1: The front-end includes phases that are independent of the target hardware. S2: The back-end includes phases that are specific to the target hardware. S3: The back-end includes phases that are specific to the programming language used in the source code. Identify the …

Consider the following $\text{ANSI C}$ program: int main () { Integer x; return 0; } Which one of the following phases in a seven-phase $C$ compiler will throw an error?

A lexical analyzer uses the following patterns to recognize three tokens $T_1, T_2$, and $T_3$ over the alphabet $\{a, b, c\}$. $T_1: a?(b \mid c)^\ast a$ $T_2: b?(a \mid c)^\ast b$ $T_3: c?(b \mid a)^\ast c$ Note that ‘$x?$’ means $0$ or $1$ occurrence of the symbol $x.$ Note also that the analyzer outputs the token that matches the …

Which one of the following statements is FALSE?

Match the following according to input (from the left column) to the compiler phase (in the right column) that processes it: …

Match the following: …

The lexical analysis for a modern computer language such as Java needs the power of which one of the following machine models in a necessary and sufficient sense?

In a compiler, keywords of a language are recognized during

Which data structure in a compiler is used for managing information about variables and their attributes?

Match all items in Group 1 with the correct options from those given in Group 2. …

The number of tokens in the following C statement is printf("i=%d, &i=%x", i, &i);

The conditional expansion facility of macro processor is provided to

Which of the following macros can put a macro assembler into an infinite loop? .MACRO M1, X .IF EQ, X ;if X=0 then M1 X + 1 .ENDC .IF NE, X ;if X ≠ O then .WORD X ;address (X) is stored here .ENDC .ENDM .MACRO M2, X .IF EQ, X M2 X .ENDC .IF NE, X .WORD X + 1 .ENDC .ENDM

The pass numbers for each of the following activities object code generation literals added to literal table listing printed address resolution of local symbols that occur in a two pass assembler respectively are

What are $x$ and $y$ in the following macro definition? macro Add x, y Load y Mul x Store y end macro

State whether the following statements are True or False with reasons for your answer A symbol declared as ‘external’ in an assembly language program is assigned an address outside the program by the assembler itself.