DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org CAB153857C7D
From: Brian Inglis <Brian.Inglis@SystematicSw.ab.ca>
Subject: Re: cpp /usr/include/threads.h fails; modfl segfaults
To: cygwin@cygwin.com
References: <02b16d2e-9d51-de58-807b-3b31b2565b59.ref@aol.com>
 <02b16d2e-9d51-de58-807b-3b31b2565b59@aol.com>
 <9f819e67-5476-ea48-a13f-f7a4b25d6e69@cornell.edu>
 <12c7b933-d06e-3b92-9c50-a1c3ad353a48@aol.com>
 <4c895636-eebc-426d-33f2-2f587a181a2d@cornell.edu>
 <871rjod54j.fsf@Otto.invalid>
Autocrypt: addr=Brian.Inglis@SystematicSw.ab.ca; prefer-encrypt=mutual;
 keydata=
 mDMEXopx8xYJKwYBBAHaRw8BAQdAnCK0qv/xwUCCZQoA9BHRYpstERrspfT0NkUWQVuoePa0
 LkJyaWFuIEluZ2xpcyA8QnJpYW4uSW5nbGlzQFN5c3RlbWF0aWNTdy5hYi5jYT6IlgQTFggA
 PhYhBMM5/lbU970GBS2bZB62lxu92I8YBQJeinHzAhsDBQkJZgGABQsJCAcCBhUKCQgLAgQW
 AgMBAh4BAheAAAoJEB62lxu92I8Y0ioBAI8xrggNxziAVmr+Xm6nnyjoujMqWcq3oEhlYGAO
 WacZAQDFtdDx2koSVSoOmfaOyRTbIWSf9/Cjai29060fsmdsDLg4BF6KcfMSCisGAQQBl1UB
 BQEBB0Awv8kHI2PaEgViDqzbnoe8B9KMHoBZLS92HdC7ZPh8HQMBCAeIfgQYFggAJhYhBMM5
 /lbU970GBS2bZB62lxu92I8YBQJeinHzAhsMBQkJZgGAAAoJEB62lxu92I8YZwUBAJw/74rF
 IyaSsGI7ewCdCy88Lce/kdwX7zGwid+f8NZ3AQC/ezTFFi5obXnyMxZJN464nPXiggtT9gN5
 RSyTY8X+AQ==
Organization: Systematic Software
Message-ID: <d59590dc-552c-db45-0049-b5a287f36773@SystematicSw.ab.ca>
Date: Sun, 30 Aug 2020 14:07:51 -0600
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101
 Thunderbird/68.12.0
MIME-Version: 1.0
In-Reply-To: <871rjod54j.fsf@Otto.invalid>
Content-Language: en-CA
Precedence: list
Reply-To: cygwin@cygwin.com
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Errors-To: cygwin-bounces@cygwin.com
Sender: "Cygwin" <cygwin-bounces@cygwin.com>

On 2020-08-30 00:23, ASSI wrote:
> Ken Brown via Cygwin writes:
>> OK, so the problem was introduced between 3.1.4 and 3.1.5.  It should
>> be pretty easy to bisect and find the culprit.  I'll do that tomorrow
>> if no one beats me to it.
> 
> The most likely culprit would be this I think:
> 
> https://sourceware.org/git/?p=newlib-cygwin.git;a=commitdiff;h=4ad9ba42fc3dd116bad8b9cb89d434256d3431fb
> 
> If so and depending on why exactly it fails, there might be more fallout
> from other similar changes.

OP debugged to display winsup/cygwin/math/modfl.c assembler that hasn't
changed since added, so compiler, build, or runtime environment updates may have
changed the code generated or used e.g. predefined symbols, build flags, runtime
CPU features.

Does Cygwin detect and allow GCC builtins to be used where available, keeping
the function available for fallback where the compiler can't use the builtin?

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

This email may be disturbing to some readers as it contains
too much technical detail. Reader discretion is advised.
[Data in IEC units and prefixes, physical quantities in SI.]
--
Problem reports:      https://cygwin.com/problems.html
FAQ:                  https://cygwin.com/faq/
Documentation:        https://cygwin.com/docs.html
Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple