Compilation process in C - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of Preprocessor Directive

What will be the output when the following C code is compiled and run?

C

#include <stdio.h>
#define SQUARE(x) x * x

int main() {
    int a = 3;
    int result = SQUARE(a + 1);
    printf("%d", result);
    return 0;
}

A 7

B 10

C 16

D Compilation error

💡 Hint

Remember how macros expand without parentheses.

The macro expands as a + 1 * a + 1 which is 3 + 1 * 3 + 1 = 3 + 3 + 1 = 7 due to operator precedence.

🧠 Conceptual

intermediate

Stages of Compilation

Which stage of the C compilation process converts assembly code into machine code?

A Linking

B Compilation

C Assembly

D Preprocessing

💡 Hint

Think about which step deals with low-level instructions.

The Assembly stage translates assembly language into machine code (object files).

🔧 Debug

advanced

Identify the Compilation Error

What error will the compiler report for this code snippet?

C

#include <stdio.h>

int main() {
    int x = 10;
    int y = 0;
    int z = x / y;
    printf("%d", z);
    return 0;
}

A Division by zero runtime error

B Compilation error: division by zero

C Warning: unused variable y

D No error, prints 0

💡 Hint

Division by zero is not caught at compile time in C.

Division by zero causes a runtime error, not a compile-time error.

📝 Syntax

advanced

Syntax Error in Macro Definition

Which option contains a syntax error that will cause the compiler to fail during preprocessing?

C

#define MAX(a, b) ((a) > (b) ? (a) : (b))

A #define MAX(a, b) (a > b ? a : b)

B #define MAX(a, b) ((a) > (b) ? (a) : (b)

C #define MAX(a, b) ((a) > (b) ? (a) : (b))

D #define MAX(a, b) ((a) > (b) ? (a) : (b));

💡 Hint

Check for balanced parentheses in macro definitions.

Option B is missing a closing parenthesis causing a syntax error during preprocessing.

🚀 Application

expert

Order of Compilation Steps

What is the correct order of the main compilation steps in C?

A 3,2,4,1

B 4,3,2,1

C 2,4,3,1

D 2,3,4,1

💡 Hint

Think about what happens first to the source code.

The source code is first preprocessed, then compiled to assembly, assembled to machine code, and finally linked.