[Bug sanitizer/56393] SIGSEGV when -fsanitize=address and dynamic lib with global objects

["kcc at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56393

Kostya Serebryany <kcc at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2013-02-19
     Ever Confirmed|0                           |1

--- Comment #6 from Kostya Serebryany <kcc at gcc dot gnu.org> 2013-02-19 18:33:32 UTC ---
The problem also shows up with clang. 
Funny. C++ global init has greater priority than C global init. 

This is the usual place from where __asan_init is called: 

gcc: 
#0  __asan_init_v1 () at ../../../../gcc/libsanitizer/asan/asan_rtl.cc:315
#1  0x0000000000417819 in _GLOBAL__sub_I_00099_1_g ()
#2  0x000000000041788d in __libc_csu_init ()
#3  0x00007ffff761b700 in __libc_start_main 
#4  0x0000000000401ec9 in _start ()

clang: 
#0  __asan_init_v1 () 
#1  0x0000000000419dcd in asan.module_ctor ()
#2  0x0000000000419e8d in __libc_csu_init ()
#3  0x00007ffff761b700 in __libc_start_main 
#4  0x0000000000419b15 in _start ()

This is where your test case crashes: 
#0  0x000000000041a864 in boost::exception_ptr
boost::get_static_exception_object<boost::bad_alloc_>() ()
#1  0x00007ffff7ff62c9 in __cxx_global_var_init () from ./libhoge.so
#2  0x00007ffff7ff62f9 in global constructors keyed to a () from ./libhoge.so
#3  0x00007ffff7de9306 in call_init 
#4  0x00007ffff7de93df in call_init 
#5  _dl_init 
#6  0x00007ffff7ddb6ea in _dl_start_user

Apparently, _dl_start_user starts before _start. 

In fact, I think that we saw something like this before and this is why 
in one of our settings we run __asan_init from the preinit array. I.e. from
here: 

#0  __asan_init_v1 () at 
#1  0x00007ffff7de943e in _dl_init
#2  0x00007ffff7ddb6ea in _dl_start_user () from /lib64/ld-linux-x86-64.so.2

Looks like it's time to enable the preinit hack by default on linux, it's
pretty stable now.
Thoughts? 

You may temporary change "defined(ASAN_USE_PREINIT_ARRAY)" to '1' in
asan_rtl.cc,
or add something like this into your code: 
  __attribute__((section(".preinit_array")))
    typeof(__asan_init) *__asan_preinit =__asan_init;