我有两个外包的共享库,用于Linux平台(无源代码,无文档)。当这些库单独链接到程序时它们可以正常工作(g++ xx.cpp lib1.so 或者 g++ xx.cpp lib2.so)。
但是,当任何C++程序同时链接到这两个共享库时,程序不可避免地会崩溃并出现“double free”错误(g++ xx.cpp lib1.so lib2.so)。
即使C++程序是一个空的“hello world”程序,与这些库没有关系,它也会崩溃。
#include <iostream>
using namespace std;
int main(){
cout<<"haha, I crash again. Catch me if you can"<<endl;
return 0;
}
Makefile:
g++ helloword.cpp lib1.so lib2.so
我得到了一些线索,这些lib1.so和lib2.so库可能共享某些公共全局变量,并且它们会两次销毁某些变量。我尝试使用gdb和valgrind,但无法从回溯中提取有用的信息。
是否有任何方法可以隔离这两个共享库并使它们以sandbox方式工作?
编辑(添加核心转储和gdb回溯):
我刚刚将上述玩具空白helloword程序与这两个库链接起来(平台:centos 7.0 64位,使用gcc4.8.2):
g++ helloworld.cpp lib1.so lib2.so -o check
Valgrind:
==29953== Invalid free() / delete / delete[] / realloc()
==29953== at 0x4C29991: operator delete(void*) (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==29953== by 0x613E589: __cxa_finalize (in /usr/lib64/libc-2.17.so)
==29953== by 0x549B725: ??? (in /home/fanbin/InventoryManagment/lib1.so)
==29953== by 0x5551720: ??? (in /home/fanbin/InventoryManagment/lib1.so)
==29953== by 0x613E218: __run_exit_handlers (in /usr/lib64/libc-2.17.so)
==29953== by 0x613E264: exit (in /usr/lib64/libc-2.17.so)
==29953== by 0x6126AFB: (below main) (in /usr/lib64/libc-2.17.so)
==29953== Address 0x6afb780 is 0 bytes inside a block of size 624 free'd
==29953== at 0x4C29991: operator delete(void*) (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==29953== by 0x613E589: __cxa_finalize (in /usr/lib64/libc-2.17.so)
==29953== by 0x4F07AC5: ??? (in /home/fanbin/InventoryManagment/lib2.so)
==29953== by 0x5039900: ??? (in /home/fanbin/InventoryManagment/lib2.so)
==29953== by 0x613E218: __run_exit_handlers (in /usr/lib64/libc-2.17.so)
==29953== by 0x613E264: exit (in /usr/lib64/libc-2.17.so)
==29953== by 0x6126AFB: (below main) (in /usr/lib64/libc-2.17.so)
gdb回溯信息:
(gdb) bt
#0 0x00007ffff677d989 in raise () from /lib64/libc.so.6
#1 0x00007ffff677f098 in abort () from /lib64/libc.so.6
#2 0x00007ffff67be197 in __libc_message () from /lib64/libc.so.6
#3 0x00007ffff67c556d in _int_free () from /lib64/libc.so.6
#4 0x00007ffff7414aa2 in __tcf_0 () from ./lib1.so
#5 0x00007ffff678158a in __cxa_finalize () from /lib64/libc.so.6
#6 0x00007ffff739f726 in __do_global_dtors_aux () from ./lib1.so
#7 0x0000000000600dc8 in __init_array_start ()
#8 0x00007fffffffe2c0 in ?? ()
#9 0x00007ffff7455721 in _fini () from ./lib1.so
#10 0x00007fffffffe2c0 in ?? ()
#11 0x00007ffff7debb98 in _dl_fini () from /lib64/ld-linux-x86-64.so.2
Backtrace stopped: previous frame inner to this frame (corrupt stack?)
更新
感谢@RaduChivu的帮助,我找到了一个非常类似的情况: 程序退出时__tcf_0导致分段错误 ,看起来确实存在两个库之间的全局变量冲突。考虑到我没有这两个外部共享库的源文件,除了使用两个独立的进程外,是否还有其他解决此冲突的方法?