Re: [PATCH v2 1/1] utils: Use fixed-point arithmetic in qemu_strtosz

[Eric Blake]

On 3/17/21 2:09 AM, Thomas Huth wrote:
> On 15/03/2021 16.58, Richard Henderson wrote:
>> Once we've parsed the fractional value, extract it into an integral
>> 64-bit fraction.  Perform the scaling with integer arithemetic, and
>> simplify the overflow detection.
> 
> I've put this patch in my local branch, but I'm still getting a failure
> in the cutils test, this time in the Cirrus-CI with the MinGW build:
> 
>  https://cirrus-ci.com/task/5413753530351616?command=test#L543
> 
> Is it related or is this a different bug?

ERROR test-cutils - Bail out!
ERROR:../tests/unit/test-cutils.c:2233:test_qemu_strtosz_trailing:
assertion failed (res == 0): (1024 == 0)

That's testing behavior on:

    str = "0x";
    err = qemu_strtosz(str, &endptr, &res);

which should parse as "0" with a suffix of 'x'.  It is an independent
issue (unrelated to the rounding issues fixed in rth's patch), and
rather appears to be a bug in mingw's libc for strtoull although I have
not actually set up an environment to test that assumption yet.

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
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