bug#26253: tests/misc/cut-huge-range.sh fails on arm-linux-gnueabihf

[Ludovic Courtès]

Hi Pádraig,

We found that ‘tests/misc/cut-huge-range.sh’ would fail on our ARMv7
GNU/Linux machines:

  https://bugs.gnu.org/26253

(I noticed there’s a thinko in the patch I used for Guix: ‘getconf
PAGESIZE’ returns bytes whereas ‘ulimit -v’ expects kibibytes).

The reason for this failure is that the limit passed to ‘ulimit -v’
would be slightly too low, even after Coreutils commit
28803c8a3144d5d4363cdbd148bbe067af1a67c2 (2004 KiB before and 3004KiB
after this commit.)

Part of the reason, I think, is that ‘vm’ is computed by simply running
‘cut -b1’:

  vm=$(get_min_ulimit_v_ cut -b1 /dev/null) \
    || skip_ "this shell lacks ulimit support"

… but the last couple of tests also run sh within that limit:

  # Explicitly disallow values above CUT_MAX
  (ulimit -v $vm && returns_ 1 cut -b$SIZE_MAX /dev/null 2>/dev/null) || fail=1
  (ulimit -v $vm && returns_ 1 cut -b$SIZE_OFLOW /dev/null 2>/dev/null) || 
fail=1

It might be more accurate to do something like:

  vm=$(get_min_ulimit_v_ sh -c 'cut -b1 /dev/null')

However it still seems easy to slightly underestimate the limit and get
those spurious failures.

Thoughts?

Ludo’.