Segmentation fault outside of main

Question

I'm working on a large, mixed C++/Fortran project. Currently, the executable segfaults immediately on startup, before reaching main, AFAICT. In fact before loading shared libraries.

Some output:

$ ./myprog
Segmentation fault (core dumped)
$ gdb ./myprog core
GNU gdb (Ubuntu 7.7-0ubuntu3) 7.7
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Reading symbols from ./myprog...done.
[New LWP 9194]
bt
Core was generated by `./myprog'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0x0000000000000001 in ?? ()
(gdb) bt
#0  0x0000000000000001 in ?? ()
#1  0x00007fff08fa02ca in ?? ()
#2  0x0000000000000000 in ?? ()

Also:

$ LD_DEBUG=all ./myprog
Segmentation fault (core dumped)

$ ldd ./myprog
    linux-vdso.so.1 =>  (0x00007fffd81fe000)
    libxerces-c-3.1.so => /usr/lib/x86_64-linux-gnu/libxerces-c-3.1.so (0x00007f774738e000)
    libxml-security-c.so.17 => /usr/lib/x86_64-linux-gnu/libxml-security-c.so.17 (0x00007f7747083000)
    libblas.so.3 => /usr/lib/libblas.so.3 (0x00007f7746ab6000)
    liblapack.so.3 => /usr/lib/liblapack.so.3 (0x00007f774631a000)
    libboost_serialization.so.1.54.0 => /usr/lib/x86_64-linux-gnu/libboost_serialization.so.1.54.0 (0x00007f77460af000)
    libboost_filesystem.so.1.54.0 => /usr/lib/x86_64-linux-gnu/libboost_filesystem.so.1.54.0 (0x00007f7745e98000)
    libboost_system.so.1.54.0 => /usr/lib/x86_64-linux-gnu/libboost_system.so.1.54.0 (0x00007f7745c94000)
    libhdf5_cpp.so.7 => /usr/lib/x86_64-linux-gnu/libhdf5_cpp.so.7 (0x00007f7745a43000)
    libhdf5.so.7 => /usr/lib/x86_64-linux-gnu/libhdf5.so.7 (0x00007f77455a6000)
    libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f7745388000)
    libgfortran.so.3 => /usr/lib/x86_64-linux-gnu/libgfortran.so.3 (0x00007f774506f000)
    libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f7744e6a000)
    libstdc++.so.6 => /usr/lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007f7744b5f000)
    libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f7744859000)
    libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007f7744641000)
    libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f774427b000)
    libcrypto.so.1.0.0 => /lib/x86_64-linux-gnu/libcrypto.so.1.0.0 (0x00007f7743ea1000)
    libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007f7743c87000)
    /lib64/ld-linux-x86-64.so.2 (0x00007f7756ed5000)
    libquadmath.so.0 => /usr/lib/x86_64-linux-gnu/libquadmath.so.0 (0x00007f7743a49000)

As can see, it depends on a fair number of libraries but crashes before LD gets to load any of them. I'm not sure where to look next. Any suggestions?

Answer 1

This was caused by compiling object files with -fPIC and the executable with -shared.