Re: strtod bugs

[Jim Meyering]

Eric Blake <address@hidden> wrote:

> According to Eric Blake on 3/30/2008 4:03 PM:
> | And just now, I tested cygwin with -O2, and got:
> |
> | ../../m4/tests/test-strtod.c:149: assertion failed
> | ../../m4/tests/test-strtod.c:221: assertion failed
> |
> | which looks like rounding errors in computing 0.1.  On further thought,
> | that particular failure is due to x86 registers having more precision than
> | memory, such that .1 (register) != .1 (memory).  So I've also changed the
> | test to use .5 instead of .1.
>
> Wow - gnulib's version of strtod really IS inaccurate.  The buildbot is
> still showing failures, since 5 * pow (10.0, -1) != 0.5.  Any suggestions
> on how to make this test pass?  Would it be acceptable (for now) to just
> check that the result is within 1 or 2 ULP of the correct answer?

Sounds good.