Re: [PATCH] Export _Unwind_Find_FDE from glibc (GCC 3.0.1 vs GLIBC 2.2.4 solution part)

[Mark Kettenis <kettenis at wins dot uva dot nl>]

   Date: Sun, 22 Jul 2001 11:44:37 -0700
   From: "H . J . Lu" <hjl@lucon.org>

   My proposal

   http://gcc.gnu.org/ml/gcc/2001-07/msg00651.html

That's not a proposal, it's a patch.

   doesn't have this problem. I patched those files so that they can be
   compiled in gcc as well as in glibc. It is an old version. I have fixed
   a few minor problems in my current version. It puts unwind-dw2.o and
   unwind-dw2.o in glibc. One thing missing is to dlopen libgcc_s.so.1
   and fall back to unwind-dw2.o and unwind-dw2.o in glibc if libgcc_s.so.1
   is missing. Also we need a way to verify the run-time libgcc_s.so.1
   is compatible with the link-time libgcc_s.so.1 at the startup time.

I think the fall-back approach introduces false security.  The
compatibility check is an orthogonal problem; see my other mail on
that issue.  I really think we should try to keep as much of the
unwinder code out of glibc as possible.  We can't get rid of the frame
registration stuff, but we don't need any of the actual unwinder code.

Fixing unwind-dw2-fde.c such that it doesn't need any functions from
unwind-dw2.c seems to be trivial.  I really think we should do that,
regardless of what we put into glibc.