topic Re: creating static object in library causing application to crash in Operating System - HP-UX

creating static object in library causing application to crash

pramodsharma — Thu, 14 May 2009 03:04:55 GMT

Here is my scenario,
1. mylib.cpp contains the code for library libfoo.sl
2. main.cpp uses the above library using dlopen.

mylib.cpp is attached and the main.cpp is like this
#include
#include
#include
typedef void (*f)(void) ;
int main()
{
void *handle = dlopen("/tmp/test/libfoo.sl",RTLD_NOW);
f cb = (f)dlsym(handle,"function");
cb();
dlclose(handle);
sleep(5);
return 0 ;
}

and the command lines are as follows
1. g++ -g -Wall -c -fPIC -D_PSTAT_64 -DPTHREAD_COMPAT_MODE -DREENTRANT -D_REENTRANT -o foo.o mylib.cpp
2. g++ -g -fPIC -shared -o libfoo.sl -lgcc_s -lstdc++ foo.o
3.gcc -g -Wl,-E main.cpp -o testexecutable

At the program exit there is a segmentation fault and the core is getting generated. Core is not telling much .

May be some flags at compile time or I am doing something really bad in code.

If I remove the static inside the void tuctuc() then everything works fine.

Any pointers will be appreciated.

Thanks,
Pramod

Re: creating static object in library causing application to crash

Dennis Handly — Thu, 14 May 2009 05:18:38 GMT

Step 3 is broken, you must link with g++, otherwise I get unsats on IPF.

You are out of luck, g++ is broken and doesn't handle dlclose with destruction of function scope statics. (I was using 4.2.1.)

aCC6 is designed to handle it.

Re: creating static object in library causing application to crash

pramodsharma — Thu, 14 May 2009 06:17:54 GMT

Thanks Denis. About this 3rd step we tried both gcc and g++ with the same result.

Ya even I figured that out that somehow g++ has some issues here but your confirmation will definetly help.

I am using gcc 4.0.1 so even moving to newer version is not going to help. Will recommend aCC to our team for next release.

Re: creating static object in library causing application to crash

Dennis Handly — Fri, 15 May 2009 01:18:31 GMT

Our g++ expert says this is a known problem. It is due to the differences in atexit(3) between libc on HP-UX and on Linux.