MCQ Compiler Test | Master Online!

1) A tokenizer is a program that:

2) What is the defining difference between a compiler and a pre-processor?

3) Language implementations based on interpretation are almost always slower than implementation based on compilation. Why, then, do people still use interpreter?

4) Numerous compilers are divided into two mostly autonomous stages: an initial phase (called: front-end) that examines the source code, and a subsequent phase (called: back-end) responsible for generating the desired target code. What constitutes the primary impetus behind this bifurcation into distinct stages?

5) A parser:

6) Total number of times a new symbol can be added to any FIRST set of LL(1) grammar without ε-productions is limited by:

7) Consider the following statements about the main differences between a compiler and an interpreter?

STATEMENT1: A compiler builds an executable binary object file that can be run again many times, whereas an interpreter produces executable code directly in temporary memory that can only be run once.

STATEMENT2: A compiler reads all of the input file before it begins translation, whereas an interpreter reads only a small section of the input file (e.g. a single line) and transliterates the line into executable code.

STATEMENT3: A compiler will build a table of symbols and perform both syntactic analysis and semantic analysis, whereas an interpreter usually only examines the syntax rules of the input language.

STATEMENT4: A compiler can perform optimizations on the input code, but an interpreter typically will not optimize the input code.

STATEMENT5: Compilation is an off-line process, interpretation is an on-line process.

Which of the following statements are TRUE?

8) A common way to define a programming language’s syntax is to use a:

9) Maximum number of elements in a FIRST set of LL(1) grammar without ε-productions is equivalent to:

10) A UNIX LEX program is used to define the:

11) Left factoring is a technique that can be used to:

STATEMENT1: Prepare a grammar for use in a recursive descent parser.

STATEMENT2: Produce a leftmost derivation of a string from a grammar

STATEMENT3: Remove left recursion from a grammar

STATEMENT4: Factor out left associative operators

STATEMENT5: Eliminate a non-terminal from the left side of a grammar rule.

STATEMENT6: All of the previous answers.

STATEMENT7: None of the previous answers.

Which of the following statements are TRUE?

12) A reduce/reduce conflict occurs when:

13) The UNIX YACC utility program parser input using a:

14) A LR(1) parser:

STATEMENT1: Processes the input symbols from left to right.

STATEMENT2: Produces a leftmost derivation.

STATEMENT3: Looks ahead at most one input symbol before knowing what action to take.

STATEMENT4: Takes time proportional to the cube of the number of input symbols.

Which of the following statements are TRUE?

15) Which of the following is true of attribute grammars?

16) For the intermediate code assignment:

17) Consider the following Context Free Grammar (CFG):

list → ids ;

ids → ids , id

→ id

Which of the following is a sentential form for this language?

18) In an attribute grammar, what is the difference between synthesized and inherited attributes?

19) For each of the following actions, state whether it happens:

(1) at compiler construction time (i.e., when developing the compiler),

(2) at compile time (i.e., when compiling or linking a program), or

(3) at run-time (i.e., when executing the code generated by the compiler).

In some cases, multiple answers are possible (i.e., an action can happen at either of two different times in different situations). For example, evaluating an arithmetic expression can happen:

(1) at compile-time, if all operands have known constant values,

(2) at runtime otherwise.

PART-1: Compute the numerical offset for a local variable within a stack frame for the C programming language.

(A) Compiler construction time          (B) Compile time        (C) Run-time   (D) None of these

PART-2: Choose the order of evaluation of the operators in a single expression.

(A) Compiler construction time          (B) Compile time        (C) Run-time   (D) None of these

PART-3: Choose the representation (data structures) to use for a 3-address code intermediate representation.

(A) Compiler construction time          (B) Compile time        (C) Run-time   (D) None of these

PART-4: Choose whether to use the mid-level or low-level model of compilation.

(A) Compiler construction time          (B) Compile time        (C) Run-time   (D) None of these

PART-5: Choose between numerical values and control flow as the strategy for compiling a relational expression.

(A) Compiler construction time          (B) Compile time        (C) Run-time   (D) None of these

Select the correct option.

20) An interpreter:

21) A parsing algorithm which performs a LEFT TO RIGHT SCAN and a RIGHTMOST DERIVATION is:

22) Put the following algorithms in order from LEAST powerful to MOST powerful: LR(0), LR(1), LALR(1), SLR.

23) What is a sentential form?

24) Consider the following C/C++ code.

01: struct Car {

02: int seats;

03: float length;

04: };

05:

06: int main(void) {

07: Car one, two, three;

08: one.seats = 4;

09: one.length = 1.23;

10: two.seats = 5;

11: two length = 2.34;

12: three = one + two;

13: return 0;

14: }

Do you think that it would fail during?

25) A parsing algorithm which performs a left to right scan and a leftmost derivation is:

26) Attribute grammars are typically used to:

27) If a grammar conforms to a classification given in one of these lists, then it automatically conforms to all grammar classifications listed to the right of it.

28) Number of FIRST set of LL(1) grammar is equivalent to:

29) What is the significance of L-attributed attribute grammars?

30) Which of the following is a checked dynamic semantic error in C (one the language implementation is required to catch at run time)?