==13279== Memcheck, a memory error detector
==13279== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==13279== Using Valgrind-3.15.0.GIT and LibVEX; rerun with -h for copyright info
==13279== Command: _test/bin/test_popen_read ./_test/work/test_32
==13279== Parent PID: 13274
==13279==
==13279== Invalid write of size 1
==13279==    at 0x4C3720B: memmove (vg_replace_strmem.c:1271)
==13279==    by 0x4E3E4EC: so_fread (so_stdio.c:173)
==13279==    by 0x109212: main (test_popen_read.c:80)
==13279==  Address 0x5638ec0 is 0 bytes after a block of size 16,000 alloc'd
==13279==    at 0x4C2FDFB: malloc (vg_replace_malloc.c:309)
==13279==    by 0x109057: main (test_popen_read.c:51)
==13279==
==13279==
==13279== HEAP SUMMARY:
==13279==     in use at exit: 0 bytes in 0 blocks
==13279==   total heap usage: 11 allocs, 11 frees, 26,611 bytes allocated
==13279==
==13279== All heap blocks were freed -- no leaks are possible
==13279==
==13279== For lists of detected and suppressed errors, rerun with: -s
==13279== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 0 from 0)