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Subject: Re: please add bear package
To: cygwin@cygwin.com
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From: Brian Inglis <Brian.Inglis@SystematicSw.ab.ca>
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Message-ID: <1449c825-422f-2646-88b9-77a2c69fea52@SystematicSw.ab.ca>
Date: Wed, 16 Sep 2020 09:50:11 -0600
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On 2020-09-16 08:42, Eliot Moss wrote:
> On 9/16/2020 10:35 AM, Brian Inglis wrote:
>> On 2020-09-15 23:34, Thomas Wolff wrote:
>>> Am 16.09.2020 um 05:27 schrieb anlex N via Cygwin:
>>>> Bear is a tool that generates a compilation database for clang tooling.
>>> You cannot expect anyone to go on bear hunt and make a package for you.
>>> On the cygwin.com page you find information about how to propose and build
>>> packages.
>>
>> "Bear currently only works on Unix-based systems (FreeBSD, GNU/Linux and macOS),
>> since it’s heavily relying on the LD_PRELOAD mechanism on *BSD/Linux and its
>> macOS counterpart to intercept the system calls."
> 
> Some old posts suggest that LD_PRELOAD works for overloading functions that
> Cygwin provides.  I can't swear to it myself :-) ...

There's functionality there but no docs to say what's possible:

- does dlsym(RTLD_DEFAULT,name) return the original entry point,
  as (unsupported) RTLD_NEXT would on other systems?
- can they hook core Cygwin, newlib, library package dynamic,
  static entry points?
- can it decide whether to call original, change return code?

Would probably be an R&D exercise, not just a straight port.

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

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