libbacktrace patch committed: Don't exit Mach-O dyld loop on failure

[Ian Lance Taylor via Gcc-patches]

This libbacktrace patch changes the loop over dynamic libraries on
Mach-O to keep going if we fail to find the debug info for a
particular library.  We can still pick up debug info for other
libraries even if one fails.  Tested on x86_64-pc-linux-gnu which
admittedly does little, but others have tested it on Mach-o.
Committed to mainline.

Ian

* macho.c (backtrace_initialize) [HAVE_MACH_O_DYLD_H]: Don't exit
loop if we can't find debug info for one shared library.

d8ddf1fa098fa50929ea0a1569a8e38d80fadbaf
diff --git a/libbacktrace/macho.c b/libbacktrace/macho.c
index 3f40811719e..16f406507d2 100644
--- a/libbacktrace/macho.c
+++ b/libbacktrace/macho.c
@@ -1268,7 +1268,7 @@ backtrace_initialize (struct backtrace_state *state, 
const char *filename,
       mff = macho_nodebug;
       if (!macho_add (state, name, d, 0, NULL, base_address, 0,
                      error_callback, data, &mff, &mfs))
-       return 0;
+       continue;
 
       if (mff != macho_nodebug)
        macho_fileline_fn = mff;