valgrind --track-origins=yes --leak-check=full --show-leak-kinds=all ./foo matrix2 2
==3159== Memcheck, a memory error detector
==3159== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==3159== Using Valgrind-3.14.0 and LibVEX; rerun with -h for copyright info
==3159== Command: ./foo matrix2 2
==3159==
index = 0, op.id = 0, buf[i] = A
index = 0, op.id = 0, buf[i] = *
index = 1, op.id = 0, buf[i] = B
2 1
1 1
*
1 1
2 1
=
4 3
3 2
==3159==
==3159== HEAP SUMMARY:
==3159==     in use at exit: 0 bytes in 0 blocks
==3159==   total heap usage: 7 allocs, 7 frees, 5,800 bytes allocated
==3159==
==3159== All heap blocks were freed -- no leaks are possible
==3159==
==3159== For counts of detected and suppressed errors, rerun with: -v
==3159== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)