`IOError: [Errno 0] Error` when comparing two 11MB ELF files

first of all: thank you so much for your very useful online service :D :D

When I try to compare two ELF binaries, each roughly 11MB in size (at https://try.diffoscope.org/pvrvdpvsztxf), I got the following from try.diffoscope.org after some minutes of "please wait":

WARNING: Your kernel does not support memory limit capabilities. Limitation discarded.
{"msg": "a/ppx_deriving [.rodata]", "total": 528366433, "current": 24016657}
{"msg": "a/ppx_deriving [.gnu.hash]", "total": 528366433, "current": 48033313}
{"msg": "a/ppx_deriving [.hash]", "total": 528366433, "current": 72049969}
{"msg": "a/ppx_deriving [.dynstr]", "total": 528366433, "current": 96066625}
{"msg": "a/ppx_deriving [.eh_frame_hdr]", "total": 528366433, "current": 120083281}
{"msg": "a/ppx_deriving [.eh_frame]", "total": 528366433, "current": 144099937}
{"msg": "a/ppx_deriving [.text]", "total": 528366433, "current": 168116593}
{"msg": "a/ppx_deriving [.init]", "total": 528366433, "current": 192133249}
{"msg": "a/ppx_deriving [.fini]", "total": 528366433, "current": 216149905}
{"msg": "a/ppx_deriving [.plt]", "total": 528366433, "current": 240166561}
{"msg": "a/ppx_deriving [.data]", "total": 528366433, "current": 264183217}
{"msg": "a/ppx_deriving [.got.plt]", "total": 528366433, "current": 288199873}
{"msg": "a/ppx_deriving [.ctors]", "total": 528366433, "current": 312216529}
{"msg": "a/ppx_deriving [.dtors]", "total": 528366433, "current": 336233185}
{"msg": "a/ppx_deriving [.jcr]", "total": 528366432, "current": 360249841}
{"msg": "a/ppx_deriving [.got]", "total": 528366433, "current": 384266497}
{"msg": "a/ppx_deriving [.bss]", "total": 528366433, "current": 408283153}
{"msg": "a/ppx_deriving [.comment]", "total": 528366433, "current": 432299809}
{"msg": "a/ppx_deriving [.debug_str]", "total": 528366433, "current": 456316465}
{"msg": "a/ppx_deriving [.shstrtab]", "total": 528366433, "current": 480333121}
{"msg": "a/ppx_deriving [.strtab]", "total": 528366433, "current": 504349777}
{"msg": "", "total": 528366433, "current": 528366433}
{"msg": "", "total": 528366433, "current": 528366433}

Traceback (most recent call last):
  File "/usr/share/python/trydiffoscope/local/lib/python2.7/site-packages/trydiffoscope/compare/tasks.py", line 54, in execute_diffoscope
    for line in p.stderr:
IOError: [Errno 0] Error

Merged from https://github.com/lamby/try.diffoscope.org/issues/2