This seems to be http://gcc.gnu.org/PR33094, which is even applied on redhat/gcc-4_1-branch, but not on redhat/gcc-4_1-fc6 branch RHEL5 gcc is based on.
The patch is backportable to RHEL5 and is not risky.

Thanks Jakub for looking into this. 

I suggest you also check bug 503565 and bug 508735 as they reference the same make_rtl_for_nonlocal_decl function so maybe you can close three with one patch ;)

Created attachment 415636 [details]
Preprocessed source

Hi,

I tried to compile pycuda:

# /usr/bin/python setup.py build
Scanning installed packages
Setuptools installation detected at /usr/local/pycuda
Non-egg installation
Removing elements out of the way...
Already patched.
/usr/local/pycuda/setuptools-0.6c9-py2.6.egg-info already patched.
Extracting in /tmp/tmpBOz-Wu
Now working in /tmp/tmpBOz-Wu/distribute-0.6.4
Building a Distribute egg in /usr/local/pycuda
/usr/local/pycuda/setuptools-0.6c9-py2.4.egg-info already exists
/usr/local/boost /boost/  python .hpp
/usr/local/boost/stage/lib / lib boost_python .so
/usr/local/boost/stage/lib / lib boost_thread .so
/usr/local/cuda /bin/  nvcc 
/usr/local/cuda/include /  cuda .h
/usr/local/cuda/lib / lib cuda .so
/usr/local/cuda/lib / lib cuda .dylib
/usr/local/cuda/lib / lib cuda .lib
/usr/local/cuda/lib /  cuda .so
/usr/local/cuda/lib /  cuda .dylib
/usr/local/cuda/lib /  cuda .lib
/usr/local/cuda/lib /  cuda .so
/usr/local/cuda/lib /  cuda .dylib
/usr/local/cuda/lib /  cuda .lib
/usr/local/cuda/lib /  cuda .so
/usr/local/cuda/lib /  cuda .dylib
/usr/local/cuda/lib /  cuda .lib
*** Cannot find CUDA driver library. Checked locations:
   /usr/local/cuda/lib/libcuda.so
   /usr/local/cuda/lib/libcuda.dylib
   /usr/local/cuda/lib/libcuda.lib
   /usr/local/cuda/lib/cuda.so
   /usr/local/cuda/lib/cuda.dylib
   /usr/local/cuda/lib/cuda.lib
   /usr/local/cuda/lib/cuda.so
   /usr/local/cuda/lib/cuda.dylib
   /usr/local/cuda/lib/cuda.lib
   /usr/local/cuda/lib/cuda.so
   /usr/local/cuda/lib/cuda.dylib
   /usr/local/cuda/lib/cuda.lib
*** Note that this may not be a problem as this component is often installed system-wide.
/usr/lib64/python2.4/distutils/dist.py:236: UserWarning: Unknown distribution option: 'install_requires'
  warnings.warn(msg)
running build
running build_py
running build_ext
building '_driver' extension
gcc -pthread -fno-strict-aliasing -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m64 -mtune=generic -D_GNU_SOURCE -fPIC -O3 -DNDEBUG -fPIC -Isrc/cpp -I/usr/local/boost -I/usr/local/cuda/include -I/usr/lib64/python2.4/site-packages/numpy/core/include -I/usr/include/python2.4 -c src/wrapper/mempool.cpp -o build/temp.linux-x86_64-2.4/src/wrapper/mempool.o
src/cpp/mempool.hpp: In instantiation of ‘pycuda::memory_pool<<unnamed>::device_allocator>’:
src/wrapper/mempool.cpp:85:   instantiated from ‘<unnamed>::context_dependent_memory_pool<<unnamed>::device_allocator>’
src/cpp/mempool.hpp:284:   instantiated from ‘pycuda::pooled_allocation<<unnamed>::context_dependent_memory_pool<<unnamed>::device_allocator> >’
src/wrapper/mempool.cpp:100:   instantiated from here
src/cpp/mempool.hpp:48: warning: ‘class pycuda::memory_pool<<unnamed>::device_allocator>’ has virtual functions but non-virtual destructor
src/wrapper/mempool.cpp: In instantiation of ‘<unnamed>::context_dependent_memory_pool<<unnamed>::device_allocator>’:
src/cpp/mempool.hpp:284:   instantiated from ‘pycuda::pooled_allocation<<unnamed>::context_dependent_memory_pool<<unnamed>::device_allocator> >’
src/wrapper/me


.
.
.



/usr/local/boost/boost/type_traits/is_volatile.hpp:52:   instantiated from ‘boost::is_volatile<<unnamed>::pooled_host_allocation>’
/usr/local/boost/boost/type_traits/remove_const.hpp:54:   instantiated from ‘boost::detail::remove_const_impl<<unnamed>::pooled_host_allocation>’
/usr/local/boost/boost/type_traits/remove_const.hpp:61:   instantiated from ‘boost::remove_const<<unnamed>::pooled_host_allocation>’
/usr/local/boost/boost/python/object/pointer_holder.hpp:127:   instantiated from ‘void* boost::python::objects::pointer_holder<Pointer, Value>::holds(boost::python::type_info, bool) [with Pointer = std::auto_ptr<<unnamed>::pooled_host_allocation>, Value = <unnamed>::pooled_host_allocation]’
src/wrapper/mempool.cpp:278:   instantiated from here
/usr/local/boost/boost/type_traits/detail/cv_traits_impl.hpp:38: internal compiler error: in make_rtl_for_nonlocal_decl, at cp/decl.c:5067
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://bugzilla.redhat.com/bugzilla> for instructions.
Preprocessed source stored into /tmp/cccT6FJK.out file, please attach this to your bugreport.
error: command 'gcc' failed with exit status 1

gcc -v
Using built-in specs.
Target: x86_64-redhat-linux
Configured with: ../configure --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --enable-shared --enable-threads=posix --enable-checking=release --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-libgcj-multifile --enable-languages=c,c++,objc,obj-c++,java,fortran,ada --enable-java-awt=gtk --disable-dssi --enable-plugin --with-java-home=/usr/lib/jvm/java-1.4.2-gcj-1.4.2.0/jre --with-cpu=generic --host=x86_64-redhat-linux
Thread model: posix
gcc version 4.1.2 20080704 (Red Hat 4.1.2-46)

*** Bug 597380 has been marked as a duplicate of this bug. ***

In gcc-4.1.2-49.el5

An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on therefore solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHSA-2011-0025.html