[Valgrind-developers] macports valgrind 3.8.0 built with XCode clang on OS X 10.8.1 fails to start

[Andrew C. M. <and...@gm...>]

Hi -

I recently built valgrind-3.8.0 using clang from XCode 4.5, via
macports, on OS X 10.8.1. It builds successfully, but the resulting
valgrind binary doesn't work. Any invocation of valgrind (even just
'valgrind --help') fails as follows:

--2030:0:main     Root stack 0x238E20000 to 0x238F24000, a local 0x238F21FB0
--2030:0:main     Valgrind: FATAL: Initial stack switched failed.
--2030:0:main        Cannot continue.  Sorry.

Turning on debug logging doesn't reveal anything interesting:

--2127:1:debuglog DebugLog system started by Stage 1, level 1 logging requested
--2127:1:launcher no tool requested, defaulting to 'memcheck'
--2127:1:launcher valgrind_lib = /opt/local/lib/valgrind
--2127:1:launcher arch 'x86' IS NOT installed
--2127:1:launcher arch 'amd64' IS installed
--2127:1:launcher arch 'arm' IS NOT installed
--2127:1:launcher arch 'ppc32' IS NOT installed
--2127:1:launcher arch 'ppc64' IS NOT installed
--2127:1:launcher no client specified, defaulting arch to 'amd64'
--2127:1:launcher launcher_name = /opt/local/bin/valgrind
--2127:1:launcher launching /opt/local/lib/valgrind/memcheck-amd64-darwin
--2127:1:debuglog DebugLog system started by Stage 2 (main), level 1
logging requested
--2127:1:main     Welcome to Valgrind version 3.8.0 debug logging
--2127:1:main     Checking current stack is plausible
--2127:0:main     Root stack 0x238E20000 to 0x238F24000, a local 0x238F21FB0
--2127:0:main     Valgrind: FATAL: Initial stack switched failed.
--2127:0:main        Cannot continue.  Sorry.

If I rebuild valgrind with llvm-gcc-4.2 as the compiler, all is well.

Is this a known issue? I searched the bug database but nothing jumped
out. If not, does anyone have any thoughts on what may be causing this
or where to start debugging? Obviously I can work around by building
with GCC, but AFAIK clang is the future on Apple platforms so it would
be good if this worked.

Thanks,
Andrew