default. There were 2 cases where the trace code was in the else-
part of an if-statement without any compound construct to protect
against nullification. The result was that 2 unconditional statements
turned into conditional statements and wrecked havoc.
This fix has been returned to the vendor and in anticipation of a
future import committed onto the vendor branch.
compilation accordingly. The net effect is that tracing is not by
default present and that it can easily be compiled-in.
The tracer uses getenv() and printf(), which cannot be used in all
cases (ie from the debugger) and with this change we improved the
applicability of the unwinder.
This change is made on the vendor branch and given back to the
vendor for possible inclusion in future versions.
available by Hewlett-Packard under the MIT license. The unwinder is
small, clean and fast and needed little adaptation for use in the
kernel.
This import has embedded in it the changes needed to make it build
in a kernel environment.
To optimize the common case, the kernel will minimize the number
of registers saved by not saving the preserved registers. In case
access to preserved registers is needed (signal handling, ptrace)
the kernel will unwind to the context of the syscall or exception.
For this we need an unwinder.
Approved by: re (blanket)
