libunwind & _Unwind_Backtrace

Wed May 18 16:51:00 GMT 2005

Steve Ellcey writes:
 > 
 > I was looking at building java on IA64 HP-UX and I found that the java
 > library calls _Unwind_Backtrace(). Now the unwind interface for C++ is
 > standardized and does not include this routine, apparently this was
 > added for java but isn't part of any standard.
 > 
 > The reason this affects me is that on IA64 HP-UX we are currently using
 > the system libunwind and it does not include this routine. So, to build
 > java on IA64 HP-UX I have to provide this somehow. I am looking at
 > several options and would like some opinions.
Something with this functionality is essential in any language that
needs to make stack traces. 
 > Convert g++ (and java) to use the GCC libunwind. I don't really like
 > this idea because I think that it is confusing to have two libunwinds
 > and it could hinder the compatibility objects compiled with GCC and
 > objects compiled with the system compilers.
 > 
 > Create my own _Unwind_Backtrace routine separate from libunwind. This
 > should be possible using the existing system interface to libunwind,
 > but where would it live then? Could I put it in the java runtime
 > library?
Why not put it in libgcc? Then everybody can use it.
Andrew.