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From Stefan Teleman <>
Subject Re: 4.2.2 release
Date Fri, 14 Aug 2009 19:27:56 GMT
On Fri, Aug 14, 2009 at 15:18, Martin Sebor<> wrote:
> I think we should think about cutting a 4.2.2 release sometime this
> month. It's been embarrassingly long since 4.2.1. Farid (or anyone
> else), do you have anything that you'd like included in it?
> Martin


Solaris 10 10/2008 SPARC has introduced a binary incompatible change
in the POSIX and Solaris threads implementation:


Objects of type mutex_t and pthread_mutex_t must start at 8-byte
aligned addresses. Applications that do not satisfy this requirement
fail. The following error message is displayed:

*** _THREAD_ERROR_DETECTION: lock usage error detected ***
"mutex is misaligned"
"condvar is misaligned"


In reality, the run-time performance is much worse than the errata
above claims: misaligned mutexes or conditional variables cause the
program to spuriously SEGV in sometimes hard to reproduce ways [
Heisenbug ].

You can view full details of this bug/change here:

To make a long story short, Solaris Kernel Update 137111-01 introduced
an ABI incompatible implementation restriction, requiring that mutexes
and conditional variables must be 8-byte aligned. This restriction has
never been documented, nor has it ever been enforced, until Solaris 10
10/2008 [ Solaris Kernel Update 137111-01 ].

The consequence of this KU is that, the multi-threaded 32-bit SPARC
version of the Apache Standard C++ Library [ 4.2.1 ] will no longer
work, and will fail at run-time with seemingly unexplainable crashes [
the exact same build will work on Solaris versions prior to Kernel
Update 137111-01 ].

This problem is not specific to the Apache Standard C++ Library: it
will occur with any 32-bit SPARCV8 binaries which do not align mutexes
or conditional variables on an 8 byte boundary.

I have created a set of patches for the Apache Standard C++ Library,
Version 4.2.1, for this problem:

You can download the tarball with all the patches from the same URL:

These patches force an 8-byte alignment for all objects which contain
a mutex or a conditional variable, and that only for SPARC. With these
patches, all the tests perform as expected.

The patch 22.locale.numpunct.cpp.43.diff is not related to the SPARCV8
ABI change -- it is simply an avoidance of a SEGV in case the variable
first_non_c == NULL [ Solaris sprintf(3C) SEGV's on NULL char*
arguments ].


Stefan Teleman

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