GATE CS 2017 Set 1 — Question 13

MCQ+1 / -0.33MediumDynamic Memory AllocationC ProgrammingProgramming & Data StructuresPointers & Pointer Arithmetic

Programming & Data Structures → C Programming → Dynamic Memory Allocation

Last updated 5 September 2026

Question

Consider the following C code:#include <stdio.h> int *assignval(int *x, int val) { *x = val; return x; } void main () { int *x = malloc(sizeof(int)); if(NULL == x) return; x = assignval(x,0); if(x) { x = (int *)malloc(sizeof(int)); if (NULL == x) return; x = assignval(x, 10); } printf("%d\n", *x); free(x); } The code suffers from which one of the following problems:

Correct answer (D) compiles successfully but execution may result in memory leak Solution The program allocates memory to x using malloc . Inside the if(x) block, x is reassigned to a new memory block allocated by a second malloc call. The address of the first allocated block is overwritten without being freed, causing a memory leak. The free(x) at the end only frees the second block. Turn this into a strength. Explore AI-powered practice and doubt support with Success Tracker.

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Correct answer (D) compiles successfully but execution may result in memory leak Solution The program allocates memory to x using malloc . Inside the if(x) block, x is reassigned to a new memory block allocated by a second malloc call. The address of the first allocated block is overwritten without being freed, causing a memory leak. The free(x) at the end only frees the second block.

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