binutils-gdb/gdb/testsuite/gdb.python/py-unwind.c
Joel Brobecker 61baf725ec update copyright year range in GDB files
This applies the second part of GDB's End of Year Procedure, which
updates the copyright year range in all of GDB's files.

gdb/ChangeLog:

        Update copyright year range in all GDB files.
2017-01-01 10:52:34 +04:00

81 lines
2.6 KiB
C

/* This test program is part of GDB, the GNU debugger.
Copyright 2015-2017 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
/* This is the test program loaded into GDB by the py-unwind test. */
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
static void *
swap_value (void **location, void *new_value)
{
void *old_value = *location;
*location = new_value;
return old_value;
}
static void
bad_layout(void **variable_ptr, void *fp)
{
fprintf (stderr, "First variable should be allocated one word below "
"the frame. Got variable's address %p, frame at %p instead.\n",
variable_ptr, fp);
abort();
}
#define MY_FRAME (__builtin_frame_address (0))
static void
corrupt_frame_inner (void)
{
/* Save outer frame address, then corrupt the unwind chain by
setting the outer frame address in it to self. This is
ABI-specific: the first word of the frame contains previous frame
address in amd64. */
void *previous_fp = swap_value ((void **) MY_FRAME, MY_FRAME);
/* Verify the compiler allocates the first local variable one word
below frame. This is where the test unwinder expects to find the
correct outer frame address. */
if (&previous_fp + 1 != (void **) MY_FRAME)
bad_layout (&previous_fp + 1, MY_FRAME);
/* Now restore it so that we can return. The test sets the
breakpoint just before this happens, and GDB will not be able to
show the backtrace without JIT reader. */
swap_value ((void **) MY_FRAME, previous_fp); /* break backtrace-broken */
}
static void
corrupt_frame_outer (void)
{
/* See above for the explanation of the code here. This function
corrupts its frame, too, and then calls the inner one. */
void *previous_fp = swap_value ((void **) MY_FRAME, MY_FRAME);
if (&previous_fp + 1 != (void **) MY_FRAME)
bad_layout (&previous_fp, MY_FRAME);
corrupt_frame_inner ();
swap_value ((void **) MY_FRAME, previous_fp);
}
int
main ()
{
corrupt_frame_outer ();
return 0;
}