Re: [PATCH] glibc: Refactor startfiles/headers into do_libc_backend()

[Bryan Hundven <bryanhundven at gmail dot com>]

On Thu, Jun 23, 2011 at 4:34 PM, Yann E. MORIN
<yann.morin.1998@anciens.enib.fr> wrote:
> Bryan, All,
>
> On Thursday 23 June 2011 11:20:41 Bryan Hundven wrote:
>> On Wed, Jun 22, 2011 at 11:19 PM, Bryan Hundven <bryanhundven@gmail.com> wrote:
>> > # HG changeset patch
>> > # User Bryan Hundven <bryanhundven@gmail.com>
>> > # Date 1308809915 25200
>> > # Node ID 54b9dc8f9f00dce0653534c54fe2c1f6667ecc37
>> > # Parent Â8bb5151c5b01fb4d1ab7bc48cec563a1e6277304
>> > glibc: Refactor startfiles/headers into do_libc_backend()
> [--SNIP--]
>
> Very good commit message, very inexplicative. Thank you!
>
> [--SNIP patch--]
>
> Nothing special to say, looks good to me. Thanks!
>
>> I tested builds of:
>>
>> mips64-octeon-linux-gnu (eglibc 2.14) (still testing sample... will
>> commit when it passes more test-suite tests on my cn3120, and a kernel
>> runs... at least it builds ;) )
>> powerpc-e500v2-linux-gnuspe (eglibc 2.14)
>> armeb-unknown-linux-gnueabi (glibc 2.13)
>> i686-nptl-linux-gnu (glibc 2.13)
>>
>> ..on an x86_64 host.
>
> Good! That's a good indication that it's still working OK. Thanks for these
> tests, I'll do more a bit later (as I said earlier).
>
> Queued, thank you!
>
>> I noticed that both the armeb and i686 builds required unwind support.
>> Must be because I'm building on x86_64?
>>
>> From CT_LIBC_GLIBC_FORCE_UNWIND help:
>> ----------------------------------------------------------------------
>> The issue seems to be related to building NPTL on old versions
>> of glibc (and possibly eglibc as well) on some architectures
>> (seen on s390, s390x and x86_64).
>> ----------------------------------------------------------------------
>>
>> Does this mean when building on these platforms, or when building
>> cross tools targeted for these platforms?
>
> Oh, bad phrasing, bad Yann... Slap cheek...
>
> I know that it happened to me when:
> Â- running on x86_64
> Â- targetting s390{,x} and x86_64
> Â- building an old glibc
>
> Maybe we could rephrase the help message a little bit, avoiding explictly
> naming architectures, and just keeping the first part:
>
> Â Â ÂIf your toolchain fails building while building the C library
> Â Â Âstart files, or the complete C library, with a message like:
> Â Â Â Âconfigure: error: forced unwind support is required
>
> Â Â Âthen you may try setting this to 'y'. Otherwise, leave it to 'n'.

I think that defaulting to 'y' is right, if the 'build' computer is
running {x86_64, s390, s390x}.
Is that correct? I am going to test this on my i686 computer tonight
to validate this.

> But virtually all architectures crosstool-NG can target have unwind support.
> So this could maybe default to 'y'. Thoughts?
>
>> I only noticed this issue with glibc, and not with eglibc.
>
> OK, thanks for the confirmation. I did not observed that error with eglibc
> so far, but did not even tried to reproduce it just replacing eglibc for
> glibc, either.

It sounds like we need more testing. I will ponder 'testing' for a
little bit, and will respond soon with a better response.

> Regards,
> Yann E. MORIN.
>
> --
> .-----------------.--------------------.------------------.--------------------.
> | ÂYann E. MORIN Â| Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
> | +33 662 376 056 | Software ÂDesigner | \ / CAMPAIGN Â Â | Â___ Â Â Â Â Â Â Â |
> | +33 223 225 172 `------------.-------: ÂX ÂAGAINST Â Â Â| Â\e/ ÂThere is no Â|
> | http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL  Â|  v  conspiracy. Â|
> '------------------------------^-------^------------------^--------------------'
>

-Bryan

--
For unsubscribe information see http://sourceware.org/lists.html#faq