Heap Consolidation

This is the process of combining adjacent free chunks, and used to prevent fragmentation

• This does not happen with tcache and fastbin

Process

• Removes chunks from other bins (unlink)
• combines chunks
• add new combined chunk back into a bin

This is determined by the prev_inuse bit on the metadata of the chunk

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#include <stdio.h>
#include <stdlib.h>


int main() {
	char *a, *b;
	a = malloc(0x88);
	b = malloc(0x88);

	free(b);
	
	b = malloc(0x88)
	return 0;
}

Often freed chunks that adjacent to the top chunk are combined to the top chunk