[issue920] Incomplete backtrace in gdb

[Matthew Dillon]

    Also note that GCC-4 by default rolls up functions it thinks it
    can inline on a file-by-file basis.  So if function A calls function B
    and GCC thinks it can inline function B in function A, whether or
    not you've told it to, it will.  You'll then get an error for function
    B but the gdb backtrace will list the problem as being in function A.

    I've noticed this when trying to debug kernels.  I personally think
    its a mistake, along with the idiotic default numeric optimizations
    that break bounds checks.

						-Matt