Boost wrongly built for 'context' lib

Boost wrongly built for 'context' lib

[Lluís Batlle i Rossell]

Hello,

the boost library (1.66, quite outdated) is wrongly built for cygwin
regarding the 'context' lib, in a way that makes the 'coroutine2' lib
crash.

b2 should be called with "context-impl=ucontext" argument when building
it.

And programs using boost context/coroutine2 should build with the flag
-DBOOST_USE_UCONTEXT

These options are documented at the bottom of this page:
https://www.boost.org/doc/libs/1_75_0/libs/context/doc/html/context/architectures.html

And that would fix the problem here reported for the nix program.
https://github.com/NixOS/nix/issues/4360

Can someone make that fix?

I haven't tried explicitly 1.66 with that build flag, but 1.75 failed the
same way until I added that build flag.

Thank you,
Lluís.

-- 
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PGP key 7CBD1DA5 - https://emailselfdefense.fsf.org/

Re: Boost wrongly built for 'context' lib

[Lluís Batlle i Rossell]

I could get a change to boost upstream that will fix it likely in the next
release.

But that would require the cygwin boost maintainer at least to provide
that boost lib available. Nevertheless the fix is interesting as a patch
for previous boost versions though.

This patch:

https://github.com/boostorg/context/commit/e785657ec4d6a885ba2fd49c3ad8eaeac1f71a34

On Wed, Dec 16, 2020 at 02:12:23PM +0100, Lluís Batlle i Rossell wrote:
> Hello,
> 
> the boost library (1.66, quite outdated) is wrongly built for cygwin
> regarding the 'context' lib, in a way that makes the 'coroutine2' lib
> crash.
> 
> b2 should be called with "context-impl=ucontext" argument when building
> it.
> 
> And programs using boost context/coroutine2 should build with the flag
> -DBOOST_USE_UCONTEXT
> 
> These options are documented at the bottom of this page:
> https://www.boost.org/doc/libs/1_75_0/libs/context/doc/html/context/architectures.html
> 
> And that would fix the problem here reported for the nix program.
> https://github.com/NixOS/nix/issues/4360
> 
> Can someone make that fix?
> 
> I haven't tried explicitly 1.66 with that build flag, but 1.75 failed the
> same way until I added that build flag.
> 
> Thank you,
> Lluís.
> 
> -- 
> (Escriu-me xifrat si saps PGP / Write ciphered if you know PGP)
> PGP key 7CBD1DA5 - https://emailselfdefense.fsf.org/

-- 
(Escriu-me xifrat si saps PGP / Write ciphered if you know PGP)
PGP key 7CBD1DA5 - https://emailselfdefense.fsf.org/

Re: Boost wrongly built for 'context' lib

[Ken Brown]

[Please don't top-post on this list.  Thanks.]

On 12/18/2020 8:00 AM, Lluís Batlle i Rossell wrote:
> I could get a change to boost upstream that will fix it likely in the next
> release.
> 
> But that would require the cygwin boost maintainer at least to provide
> that boost lib available. Nevertheless the fix is interesting as a patch
> for previous boost versions though.
> 
> This patch:
> 
> https://github.com/boostorg/context/commit/e785657ec4d6a885ba2fd49c3ad8eaeac1f71a34

The boost maintainer has retired from Cygwin package maintenance, so nothing is 
likely to happen until a new maintainer steps forward.  Would you like to 
volunteer?  If so, start at

   https://cygwin.com/packages.html

and follow up on the cygwin-apps list if you have questions.

Ken