[Llvm-bgq-discuss] clang/bgclang

Tue May 6 13:13:39 CDT 2014

On Tuesday, May 06, 2014 16:11:37 Biddiscombe, John A. wrote:
> Hal,
> 
> In my ongoing struggle to succeed despite my repeated failures, I have
> successfully compiled boost/hpx/otherstuff with just clang++ and linked to
> libc++ from the c++11 toolchain. However, when I startup programs compiled
> as part of HPX, I get a segfault in some _dl_fixup going on during the
> initialization of a static path/dir object in boost filesystem.

Just for the record: I am not able to reproduce this issue with the 
bgclang++11 wrapper script on the CNK nodes (Unfortunately, I have no access 
to IONs).

Regards,
Thomas

> 
> The best explanation I've found from stackoverflow says
> (http://stackoverflow.com/questions/10578315/segmentation-fault-in-dl-runti
> me-resolve)
> 
>   1.  Heap corruption (overflow) or
>   2.  Mismatched parts of glibc itself.
> and 2) is clearly a possibility in my case since we're using
> libc.so.6 =>
> /bgsys/drivers/ppcfloor/gnu-linux-4.7.2/powerpc64-bgq-linux/lib/libc.so.6
> (0x00000fff78420000) which is non-standard.
> 
> Question: Is there anything in the bgclang script that does important
> setting of any var/flag which might influence how the exes get linked. I
> see stuff in particular that sets BGCLANG_TARGET_INC="-Xclang -isystem
> -Xclang
> /gpfs/bbp.cscs.ch/home/biddisco/apps/clang/bgclang/r206161-20140414/libc++/
> include $BGCLANG_TARGET_INC" and also
>                 BGCLANG_TARGET_FLAGS="$BGCLANG_TARGET_FLAGS
> -L$BGSYS_FLOOR/$GNU_LINUX/powerpc64-bgq-linux/lib" and I wonder about the
> -Xclang items which I understand to be instructions to clang plugins.
> 
> If I have my system configured as follows
> CFLAGS="-mcpu=a2"
> CXXFLAGS="-mcpu=a2 -std=c++11 -stdlib=libc++ -D_bgq_linux
> -I/gpfs/bbp.cscs.ch/home/biddisco/apps/clang/bgclang/r206161-20140414/libc+
> +/include -I/bgsys/drivers/ppcfloor" LDFLAGS="-dynamic
> -L/gpfs/bbp.cscs.ch/home/biddisco/apps/clang/bgclang/r206161-20140414/libc+
> +/lib -L/bgsys/drivers/ppcfloor/gnu-linux-4.7.2/powerpc64-bgq-linux/lib"
> (the -D_bgq_linux is mine and used by certain cpp files to #include stuff)
> 
> can you imagine what might be going wrong with my build/link to munge my
> libc initialization in any way? Have I linked to the wrong libc/c++ stuff
> perhaps? Typically my exes come out looking like this (ldd below) as far as
> libs are used, which seems ok, but they do segfault on start which is
> really annoying me a lot (understatement).
> 
> thanks
> 
> JB
> 
> bbpbg2:~/bgas/clang/build/cpp$ ldd ../hpx/bin/network_storage
>                 linux-vdso64.so.1 =>  (0x00000fff7d580000)
>                 libhpxd.so.0 =>
> /gpfs/bbp.cscs.ch/home/biddisco/bgas/clang/build/hpx/lib/hpx/libhpxd.so.0
> (0x00000fff79b00000) libhpx_serializationd.so.0 =>
> /gpfs/bbp.cscs.ch/home/biddisco/bgas/clang/build/hpx/lib/hpx/libhpx_seriali
> zationd.so.0 (0x00000fff79ac0000)
> libboost_date_time-clang35-mt-d-1_55.so.1.55.0 =>
> /gpfs/bbp.cscs.ch/home/biddisco/apps/clang/boost_1_55_0/lib/libboost_date_t
> ime-clang35-mt-d-1_55.so.1.55.0 (0x00000fff79a90000)
> libboost_filesystem-clang35-mt-d-1_55.so.1.55.0 =>
> /gpfs/bbp.cscs.ch/home/biddisco/apps/clang/boost_1_55_0/lib/libboost_filesy
> stem-clang35-mt-d-1_55.so.1.55.0 (0x00000fff79a40000)
> libboost_program_options-clang35-mt-d-1_55.so.1.55.0 =>
> /gpfs/bbp.cscs.ch/home/biddisco/apps/clang/boost_1_55_0/lib/libboost_progra
> m_options-clang35-mt-d-1_55.so.1.55.0 (0x00000fff79920000)
> libboost_regex-clang35-mt-d-1_55.so.1.55.0 =>
> /gpfs/bbp.cscs.ch/home/biddisco/apps/clang/boost_1_55_0/lib/libboost_regex-
> clang35-mt-d-1_55.so.1.55.0 (0x00000fff79710000)
> libboost_serialization-clang35-mt-d-1_55.so.1.55.0 =>
> /gpfs/bbp.cscs.ch/home/biddisco/apps/clang/boost_1_55_0/lib/libboost_serial
> ization-clang35-mt-d-1_55.so.1.55.0 (0x00000fff79530000)
> libboost_system-clang35-mt-d-1_55.so.1.55.0 =>
> /gpfs/bbp.cscs.ch/home/biddisco/apps/clang/boost_1_55_0/lib/libboost_system
> -clang35-mt-d-1_55.so.1.55.0 (0x00000fff79510000)
> libboost_thread-clang35-mt-d-1_55.so.1.55.0 =>
> /gpfs/bbp.cscs.ch/home/biddisco/apps/clang/boost_1_55_0/lib/libboost_thread
> -clang35-mt-d-1_55.so.1.55.0 (0x00000fff794c0000)
> libboost_atomic-clang35-mt-d-1_55.so.1.55.0 =>
> /gpfs/bbp.cscs.ch/home/biddisco/apps/clang/boost_1_55_0/lib/libboost_atomic
> -clang35-mt-d-1_55.so.1.55.0 (0x00000fff794a0000)
> libboost_chrono-clang35-mt-d-1_55.so.1.55.0 =>
> /gpfs/bbp.cscs.ch/home/biddisco/apps/clang/boost_1_55_0/lib/libboost_chrono
> -clang35-mt-d-1_55.so.1.55.0 (0x00000fff79480000)
> libboost_context-clang35-mt-d-1_55.so.1.55.0 =>
> /gpfs/bbp.cscs.ch/home/biddisco/apps/clang/boost_1_55_0/lib/libboost_contex
> t-clang35-mt-d-1_55.so.1.55.0 (0x00000fff79460000) libmpich.so.3 =>
> /usr/lib64/mvapich2/lib/libmpich.so.3 (0x00000fff790f0000) libibverbs.so.1
> => /usr/lib64/libibverbs.so.1 (0x000000808dbe0000) libopa.so.1 =>
> /usr/lib64/mvapich2/lib/libopa.so.1 (0x00000fff790a0000) libmpl.so.1 =>
> /usr/lib64/mvapich2/lib/libmpl.so.1 (0x00000080afc00000) librt.so.1 =>
> /bgsys/drivers/ppcfloor/gnu-linux-4.7.2/powerpc64-bgq-linux/lib/librt.so.1
> (0x00000fff78f70000) libpthread.so.0 =>
> /bgsys/drivers/ppcfloor/gnu-linux-4.7.2/powerpc64-bgq-linux/lib/libpthread.
> so.0 (0x00000fff78e50000) librdmacm.so.1 => /usr/lib64/librdmacm.so.1
> (0x000000808dc10000) libhwloc.so.5 =>
> /gpfs/bbp.cscs.ch/home/biddisco/apps/clang/hwloc-1.8.1/lib/libhwloc.so.5
> (0x00000fff78df0000) libdl.so.2 =>
> /bgsys/drivers/ppcfloor/gnu-linux-4.7.2/powerpc64-bgq-linux/lib/libdl.so.2
> (0x00000fff78cd0000) libc++.so.1 =>
> /gpfs/bbp.cscs.ch/home/biddisco/apps/clang/bgclang/libc++/lib/libc++.so.1
> (0x00000fff78ab0000) libstdc++.so.6 =>
> /bgsys/drivers/ppcfloor/gnu-linux-4.7.2/powerpc64-bgq-linux/lib/libstdc++.s
> o.6 (0x00000fff78880000) libm.so.6 =>
> /bgsys/drivers/ppcfloor/gnu-linux-4.7.2/powerpc64-bgq-linux/lib/libm.so.6
> (0x00000fff78760000) libgcc_s.so.1 =>
> /bgsys/drivers/ppcfloor/gnu-linux-4.7.2/powerpc64-bgq-linux/lib/libgcc_s.so
> .1 (0x00000fff78650000) libc.so.6 =>
> /bgsys/drivers/ppcfloor/gnu-linux-4.7.2/powerpc64-bgq-linux/lib/libc.so.6
> (0x00000fff78420000) libibumad.so.3 => /usr/lib64/libibumad.so.3
> (0x00000080a0b60000) /lib64/ld64.so.1 (0x0000000020a80000)