On 14/05/16 18:09, Jim Meyering wrote:
On systems with recent glibc, this abuse of timeout elicits the expected error:
$ src/timeout -- -1.189731495357231765e+4932 sleep 0
src/timeout: invalid time interval ‘-1.189731495357231765e+4932’
Try 'src/timeout --help' for more information.
But with glibc-2.12's strtod, that input maps to a double-precision
value of 0 rather than to -inf, so timeout does this:
$ src/timeout -- -1.189731495357231765e+4932 sleep 0; echo $?
0
Similarly, the sleep.sh test fails because even without the leading "-",
that number ($LDBL_MAX) maps to 0:
So the buggy strtod() is treating the overflow as underflow :(
$ src/timeout 0.1 sleep 1.189731495357231765e+4932; echo $?
0
which causes two tests to fail:
tests/misc/timeout-parameters
tests/misc/sleep
I see a couple of ways to avoid trouble.
Perhaps the most general is to make gnulib's strtod module detect and
compensate for these errors.
But that's CentOS6-era glibc, so maybe not worth it for such a corner case.
Has up to date centos6 the bug?
I didn't see it with glibc-2.12-1.166.el6_7.7.x86_64
cheers,
Pádraig.
