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[[!tag open_issue_glibc open_issue_libpthread]]

IRC, freenode, #hurd, 2011-10-21:

    <pinotree> maybe i'm missing something... what's the reason for not
      allowing setting a different stack size in libpthread?

2011-10-23:

    <youpi> pinotree: the threadvars implementations
    <youpi> which needs to find the variables according to sp value
    <youpi> of course, since we now have TLS, threadvards can go away
    <youpi> it's simply on the so-long TODO list

[[glibc/t/tls-threadvar]].

2012-12-28:

Hurd commit 3a3fcc811e6b50b21124a5c5a128652e788a3b67 `libports: remove the
threadvars stack size hack`.

IRC, freenode, #hurd, 2014-01-09:

    <teythoon> braunr: i'm afraid it might be your patch 3a3fcc81 that breaks
      proc
    <teythoon> w/ the current debian libc that is
    <teythoon> braunr: i reverted that patch and now it boots again
    <gnu_srs> is alternate stack and arbitrary stack sizes supported by now, or
      upcoming?
    <braunr> gnu_srs: supported
    <braunr> well
    <braunr> considering what teythoon just said, maybe not
    <gg0> need to remove __pthread_stack_default_size from
      libpthread_hurd_cond_wait patch too i guess
    <braunr> teythoon: i don't understand why this change has any negative
      effect :/
    <braunr> or
    <braunr> hm no ..
    <braunr> there may be a bug in the latest glibc, where changing the stack
      is allowed on the ground that threadvars have been replaced with tls, but
      the libpthread stack handling code does it wrong
    <braunr> see 714413a7694ff534855e9e5904899695eac6c9bb in libpthread
    <braunr> which the thread destruction patches already did before it was
      fixed in libpthread
    <braunr> and may explain why my packages work


IRC, freenode, #hurd, 2014-01-14:

    <youpi> teythoon: Mmm, I tried to update to the latest hurd commits, but
      init dies early at boot
    <youpi> exec init proc auth, and then init crashes
    <youpi> downgrading libports to previous makes the issue go away
    <braunr> youpi: previous ?
    <youpi> previous debian package
    <braunr> which patch makes it fail ?
    <youpi> I'm bisecting
    <braunr> i remember teythoon saying he had failures with the patch that
      removes the threadvars stack size hack
    <youpi> I'll try that already, ok
    <youpi> yes, boots fine without this change
    <braunr> ok
    <youpi> perhaps some missing patches in the current 2.17-97 glibc
    <braunr> or libpthread reacting badly to new stack sizes
    <braunr> is 714413a7694ff534855e9e5904899695eac6c9bb included in your glibc
      ?
    <braunr> (714413a7694ff534855e9e5904899695eac6c9bb from libpthread)
    <braunr> or maybe that's not the problem
    <braunr> anyway, it's normally fixed with the thread destruction patch
    <braunr> i did test it and checked the stack size were correct
    <braunr> sizes*
    <youpi> yes, debian's glibc has it
    <youpi> ok
    <youpi> so that can wait
    <braunr> is 959f7365fccd1c89be9938c2655eba9122171e6a (Drop threadvars
      entirely) also in your glibc ?
    <youpi> yes
    <braunr> that's weird :/
    <braunr> the only thing i can think of is __pthread_stack_alloc miserably
      failing with 2M stacks and "many" threads for some odd reason ..
    <braunr> anyway, see you tomorrow
    <gg0> hurd-i386/libpthread_hurd_cond_wait.diff keeps using
      __pthread_stack_default_size. isn't it the problem?
    * youpi wonders what that change is doing there
    <youpi> and it's there from the start of that patch...
    <braunr> +  if (&__pthread_stack_default_size != NULL)
    <braunr> checks if the symbol is actually resolved
    <braunr> that's what allows regular applications to work
    <braunr> it should be the same for hurd servers


# sigaltstack

Likewise, `sigaltstack` is not usable at the moment.

IRC, freenode, #hurd, 2014-02-25:

    <gnu_srs> braunr: are the split/alternate stack etc problems solved by now
      so gccgo can work properly?
    <braunr> i don't know
    <braunr> i suspect it wouldn't require much work now that tls is well
      supported
    <youpi> alternate stack is supposed to be working