From: "Gabriel F. T. Gomes" <gabriel@inconstante.eti.br>
To: Tulio Magno Quites Machado Filho <tuliom@linux.vnet.ibm.com>
Cc: <libc-alpha@sourceware.org>
Subject: Re: [PATCH v3 2/5] powerpc: Add redirection for finitef128, isinf128, and isnanf128
Date: Tue, 19 Sep 2017 15:12:00 -0000 [thread overview]
Message-ID: <20170919121220.1229d368@keller.br.ibm.com> (raw)
In-Reply-To: <87efr2izs5.fsf@linux.vnet.ibm.com>
On 19 Sep 2017, Tulio Magno Quites Machado Filho wrote:
>"Gabriel F. T. Gomes" <gabriel@inconstante.eti.br> writes:
>
>> The errors are due to the unintended macro expansion of __finitef128 to
>> __redirect_finitef128 in math/bits/mathcalls-helper-functions.h. In
>
>AFAIU, the expansion of __finitef128 to __redirect_finitef128 in
>math/bits/mathcalls-helper-functions.h is expected. The problem happens when
>the same thing doesn't happen in include/math.h too.
I mean unintended in the sense that the expansion of __finitef and
__finitel, which pertain to float and long double, are happening in
s_finite.c, which is the *double* implementation of finite. Compare that
with s_finitef.c, which only redefines __finitef, leaving the other macros
(__finite and __finitel) untouched.
On the other hand, I agree that my comments did not fully explain the
problem. They only mention the expansion in mathcalls-helper-functions.h
and do not say anything about the hidden prototypes in include/math.h.
So, how about expanding this paragraph to:
The errors are due to the unintended macro expansion of __finitef128 to
__redirect_finitef128 in math/bits/mathcalls-helper-functions.h. In
that header, __MATHDECL_1 takes '__finite' and 'f128' as arguments and
concatenates them. However, since '__finite' has been redefined in
s_finite.c, the function declaration becomes __redirect_finitef128:
extern int __redirect___finitef128 (_Float128 __value) __attribute__ ((__nothrow__ )) __attribute__ ((__const__));
This declaration itself is OK. The problem arises when include/math.h
creates the hidden prototype ('hidden_proto (__finitef128)'), which
expands to:
extern __typeof (__finitef128) __finitef128 __attribute__ ((visibility ("hidden")));
Since __finitef128 is not declared, __typeof fails. This effect was
already true for the 'float' and 'long double' versions and is now true
for float128. Likewise for isinsff128 and isnanf128.
>> +/* The following definitions, although not related to the 'double'
>> + version of 'finite', are required to compensate for the unintended
>> + macro expansion of __finitef to __redirect___finitef, etc. in
>> + math/bits/mathcalls-helper-functions.h. */
>
>Likewise.
>I suggest the following change:
>
>/* The following definitions, although not related to the 'double'
> version of 'finite', are required to guarantee the macro expansion
> of __finitef to __redirect___finitef, etc. in
> math/bits/mathcalls-helper-functions.h and include/math.h. */
The expansion in mathcalls-helper-functions.h is unintended, but we need
to guarantee the same expansion in include/math.h, so what about the
following:
The following definitions, although not related to the 'double' version
of 'finite', are required to guarantee expansions (e.g.: from __finitef
to __redirect_finitef) in include/math.h, thus compensating for the
unintended macro expansions in math/bits/mathcalls-helper-functions.h.
OK with these changes?
next prev parent reply other threads:[~2017-09-19 15:12 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-09-12 12:34 [PATCH v3 0/5] Fixes for gcc enabling -mfloat128 by default Gabriel F. T. Gomes
2017-09-12 12:34 ` [PATCH v3 1/5] powerpc64le: Add -mfloat128 to tst-strtod-nan-locale testcase Gabriel F. T. Gomes
2017-09-18 20:45 ` Tulio Magno Quites Machado Filho
2017-09-12 12:34 ` [PATCH v3 2/5] powerpc: Add redirection for finitef128, isinf128, and isnanf128 Gabriel F. T. Gomes
2017-09-19 13:28 ` Tulio Magno Quites Machado Filho
2017-09-19 15:12 ` Gabriel F. T. Gomes [this message]
2017-09-20 13:46 ` Tulio Magno Quites Machado Filho
2017-09-12 12:35 ` [PATCH v3 3/5] ldbl-128ibm: Copy implementations from ldbl-128 instead of including them Gabriel F. T. Gomes
2017-09-12 14:41 ` Joseph Myers
2017-09-12 12:35 ` [PATCH v3 4/5] ldbl-128ibm: Automatic replacing of _Float128 and L() Gabriel F. T. Gomes
2017-09-12 14:43 ` Joseph Myers
2017-09-12 12:35 ` [PATCH v3 5/5] Remove conditional on LDBL_MANT_DIG from e_lgammal_r.c Gabriel F. T. Gomes
2017-09-12 14:43 ` Joseph Myers
2017-09-21 21:31 ` [PATCH v3 0/5] Fixes for gcc enabling -mfloat128 by default Gabriel F. T. Gomes
2017-09-22 18:43 ` Tulio Magno Quites Machado Filho
2017-09-26 6:13 ` Florian Weimer
2017-10-09 14:10 ` Gabriel F. T. Gomes
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20170919121220.1229d368@keller.br.ibm.com \
--to=gabriel@inconstante.eti.br \
--cc=libc-alpha@sourceware.org \
--cc=tuliom@linux.vnet.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).