Re: GDB does not stop in breakpoint!

[Richard Stallman]

    3       breakpoint     keep y   0x081fc176 in funcall_lambda at eval.c:3147
            stop only if EQ(XCDR(XCAR(arg_vector[0])),Qx)
            breakpoint already hit 411 times


    It stops even if XCDR(XCAR(arg_vector[0])) != 'x

I did not know it was possible to use C macros in GDB.
But if that does work now, I do not see why this condition would fail
to work correctly.

But it is clear that that fails to verify whether arg_vector[0]
is a cons cell.  So it will sometimes match objects that are the
wrong type.

Therefore, it is certain that this

    cond 3 (CONSP(arg_vector[0]) && CONSP(XCAR(arg_vector[0])) &&
    EQ(XCAR(XCAR(arg_vector[0])),Qx))

is the right command to use.