[libunwind] Re: libunwind subscription

[David Mosberger]

>>>>> On Wed, 27 Aug 2003 10:46:42 +0200, "Karl Ostner" <address@hidden> said:

  Karl> BTW, tests-ptrace (which is the only test using remote
  Karl> unwinding that I've found) is failing on the machine I'm
  Karl> running on. This is expected, according to your README, for
  Karl> glibc < 2.3.1.  I have glibc 2.2.4, cc is 3.0.4 (pretty old, I
  Karl> know, but I cannot upgrade, its not my box, and there is
  Karl> currently no newer one available).

  Karl> Is there any way to get remote unwinding working on glibc
  Karl> 2.2.4, or is a glibc upgrade to >= 2.3.1 a prerequisite ?

A clarification is needed here: the test-ptrace test-case will fail
with old libcs, but remote unwinding works just fine.  For example,
try:

        test-ptrace -v /bin/echo hello

On my home system (libc-2.2.5) this will produce a long list of
backtraces with a grand total of just 40 errors.  Those errors are
basically due to lack of unwind info for the code in the init/fini
section (newer libc/gcc combos use init_array/fini_array instead).

Anyhow, it's unusual to do a backtrace at that point in time, so these
errors are unlikely to affect practical use of libunwind very much.

        --david