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8 commits

Author SHA1 Message Date
Joel Brobecker
32d0add0a6 Update year range in copyright notice of all files owned by the GDB project.
gdb/ChangeLog:

        Update year range in copyright notice of all files.
2015-01-01 13:32:14 +04:00
Andrew Burgess
53e8a631a0 Add a TRY_CATCH to get_prev_frame_always to better manage errors during unwind.
https://sourceware.org/ml/gdb-patches/2014-05/msg00737.html

Currently a MEMORY_ERROR raised during unwinding a frame will cause the
unwind to stop with an error message, for example:

  (gdb) bt
  #0  breakpt () at amd64-invalid-stack-middle.c:27
  #1  0x00000000004008f0 in func5 () at amd64-invalid-stack-middle.c:32
  #2  0x0000000000400900 in func4 () at amd64-invalid-stack-middle.c:38
  #3  0x0000000000400910 in func3 () at amd64-invalid-stack-middle.c:44
  #4  0x0000000000400928 in func2 () at amd64-invalid-stack-middle.c:50
  Cannot access memory at address 0x2aaaaaab0000

However, frame #4 is marked as being the end of the stack unwind, so a
subsequent request for the backtrace looses the error message, such as:

  (gdb) bt
  #0  breakpt () at amd64-invalid-stack-middle.c:27
  #1  0x00000000004008f0 in func5 () at amd64-invalid-stack-middle.c:32
  #2  0x0000000000400900 in func4 () at amd64-invalid-stack-middle.c:38
  #3  0x0000000000400910 in func3 () at amd64-invalid-stack-middle.c:44
  #4  0x0000000000400928 in func2 () at amd64-invalid-stack-middle.c:50

When fetching the backtrace, or requesting the stack depth using the MI
interface the situation is even worse, the first time a request is made
we encounter the memory error and so the MI returns an error instead of
the correct result, for example:

  (gdb) -stack-info-depth
  ^error,msg="Cannot access memory at address 0x2aaaaaab0000"

Or,

  (gdb) -stack-list-frames
  ^error,msg="Cannot access memory at address 0x2aaaaaab0000"

However, once one of these commands has been used gdb has, internally,
walked the stack and figured that out that frame #4 is the bottom of the
stack, so the second time an MI command is tried you'll get the "expected"
result:

  (gdb) -stack-info-depth
  ^done,depth="5"

Or,

  (gdb) -stack-list-frames
  ^done,stack=[frame={level="0", .. snip lots .. }]

After this patch the MEMORY_ERROR encountered during the frame unwind is
attached to frame #4 as the stop reason, and is displayed in the CLI each
time the backtrace is requested.  In the MI, catching the error means that
the "expected" result is returned the first time the MI command is issued.
So, from the CLI the results of the backtrace will be:

  (gdb) bt
  #0  breakpt () at amd64-invalid-stack-middle.c:27
  #1  0x00000000004008f0 in func5 () at amd64-invalid-stack-middle.c:32
  #2  0x0000000000400900 in func4 () at amd64-invalid-stack-middle.c:38
  #3  0x0000000000400910 in func3 () at amd64-invalid-stack-middle.c:44
  #4  0x0000000000400928 in func2 () at amd64-invalid-stack-middle.c:50
  Backtrace stopped: Cannot access memory at address 0x2aaaaaab0000

Each and every time that the backtrace is requested, while the MI output
will similarly be consistently:

  (gdb) -stack-info-depth
  ^done,depth="5"

Or,

  (gdb) -stack-list-frames
  ^done,stack=[frame={level="0", .. snip lots .. }]

gdb/ChangeLog:

	* frame.c (struct frame_info): Add stop_string field.
	(get_prev_frame_always_1): Renamed from get_prev_frame_always.
	(get_prev_frame_always): Old content moved into
	get_prev_frame_always_1.  Call get_prev_frame_always_1 inside
	TRY_CATCH, handle MEMORY_ERROR exceptions.
	(frame_stop_reason_string): New function definition.
	* frame.h (unwind_stop_reason_to_string): Extend comment to
	mention frame_stop_reason_string.
	(frame_stop_reason_string): New function declaration.
	* stack.c (frame_info): Switch to frame_stop_reason_string.
	(backtrace_command_1): Switch to frame_stop_reason_string.
	* unwind_stop_reason.def: Add UNWIND_MEMORY_ERROR.
	(LAST_ENTRY): Changed to UNWIND_MEMORY_ERROR.
	* guile/lib/gdb.scm: Add FRAME_UNWIND_MEMORY_ERROR to export list.

gdb/doc/ChangeLog:

	* guile.texi (Frames In Guile): Mention FRAME_UNWIND_MEMORY_ERROR.
	* python.texi (Frames In Python): Mention
	gdb.FRAME_UNWIND_MEMORY_ERROR.

gdb/testsuite/ChangeLog:

	* gdb.arch/amd64-invalid-stack-middle.exp: Update expected results.
	* gdb.arch/amd64-invalid-stack-top.exp: Likewise.
2014-05-30 22:44:36 +01:00
Joel Brobecker
ecd75fc8ee Update Copyright year range in all files maintained by GDB. 2014-01-01 07:54:24 +04:00
Pedro Alves
20e1ca3bc1 UNWIND_NULL_ID is no longer used anywhere. Update comments.
Unfortunately, UNWIND_NULL_ID is exported to Python as
gdb.FRAME_UNWIND_NULL_ID so we can't really eliminate it.

(I'd assume scripts just check the result of Frame.unwind_stop_reason,
and compare it to gdb.FRAME_UNWIND_NO_REASON.  That at most, they'll
pass the result of Frame.unwind_stop_reason to
gdb.frame_stop_reason_string.  I'd prefer to just get rid of it, but
because we make an API promise, we get to keep this around for
compatibility, in case a script does refer to gdb.FRAME_UNWIND_NULL_ID
directly.)

gdb/
2013-11-29  Pedro Alves  <palves@redhat.com>

	* unwind_stop_reasons.def (UNWIND_NULL_ID): Update comment.

gdb/doc/
2013-11-29  Pedro Alves  <palves@redhat.com>

	* gdb.texinfo (Frames In Python) <gdb.FRAME_UNWIND_NULL_ID>:
	Update comment.
2013-11-29 15:25:46 +00:00
Pedro Alves
0b1afbb37b Consistent use of (C) after "Copyright".
While writing the previous patch, I noticed that we're not consistent
with the (C) in the copyright header.  The maintainers manual prefers
having it, though also says it's optional.  We have over 10x more
files with (C) than without in gdb's code, so I spent a few minutes
grepping and fixing.  Funny enough, the testsuite has it backwards.
I'll leave that for another time.

gdb/
2013-02-12  Pedro Alves  <palves@redhat.com>

	* amd64-darwin-tdep.c: Add (C) after Copyright.
	* cli/cli-cmds.h: Ditto.
	* cli/cli-decode.c: Ditto.
	* cli/cli-decode.h: Ditto.
	* cli/cli-dump.c: Ditto.
	* cli/cli-dump.h: Ditto.
	* cli/cli-interp.c: Ditto.
	* cli/cli-logging.c: Ditto.
	* cli/cli-script.c: Ditto.
	* cli/cli-script.h: Ditto.
	* cli/cli-setshow.c: Ditto.
	* cli/cli-setshow.h: Ditto.
	* cli/cli-utils.c: Ditto.
	* cli/cli-utils.h: Ditto.
	* config/alpha/nm-osf3.h: Ditto.
	* config/djgpp/djconfig.sh: Ditto.
	* config/i386/nm-fbsd.h: Ditto.
	* config/i386/nm-i386gnu.h: Ditto.
	* config/nm-linux.h: Ditto.
	* config/nm-nto.h: Ditto.
	* config/rs6000/nm-rs6000.h: Ditto.
	* config/sparc/nm-sol2.h: Ditto.
	* darwin-nat-info.c: Ditto.
	* dfp.c: Ditto.
	* dfp.h: Ditto.
	* gdb-demangle.h: Ditto.
	* i386-darwin-nat.c: Ditto.
	* i386-darwin-tdep.c: Ditto.
	* linux-fork.h: Ditto.
	* m32c-tdep.c: Ditto.
	* microblaze-linux-tdep.c: Ditto.
	* microblaze-rom.c: Ditto.
	* microblaze-tdep.c: Ditto.
	* microblaze-tdep.h: Ditto.
	* mips-linux-tdep.h: Ditto.
	* ppc-ravenscar-thread.c: Ditto.
	* ppc-ravenscar-thread.h: Ditto.
	* prologue-value.c: Ditto.
	* prologue-value.h: Ditto.
	* ravenscar-thread.c: Ditto.
	* ravenscar-thread.h: Ditto.
	* sparc-ravenscar-thread.c: Ditto.
	* sparc-ravenscar-thread.h: Ditto.
	* tilegx-linux-tdep.c: Ditto.
	* unwind_stop_reasons.def: Ditto.
	* windows-nat.h: Ditto.
	* xtensa-linux-tdep.c: Ditto.
	* xtensa-xtregs.c: Ditto.
	* regformats/regdat.sh: Ditto.
	* regformats/regdef.h: Ditto.

gdb/gdbserver/
2013-02-12  Pedro Alves  <palves@redhat.com>

	* linux-xtensa-low.c: Ditto.
	* xtensa-xtregs.c: Ditto.
2013-02-12 19:03:57 +00:00
Joel Brobecker
8acc9f485b Update years in copyright notice for the GDB files.
Two modifications:
  1. The addition of 2013 to the copyright year range for every file;
  2. The use of a single year range, instead of potentially multiple
     year ranges, as approved by the FSF.
2013-01-01 06:41:43 +00:00
Joel Brobecker
c5a5708100 Copyright year update in most files of the GDB Project.
gdb/ChangeLog:

        Copyright year update in most files of the GDB Project.
2012-01-04 08:28:28 +00:00
Kevin Pouget
2231f1fb60 Move unwind reasons to an external .def file
gdb/
	* frame.c (frame_stop_reason_string): Rewrite using
	unwind_stop_reasons.def.
	* frame.h (enum unwind_stop_reason): Likewise.
	* python/py-frame.c (gdbpy_initialize_frames): Likewise.
	(gdbpy_frame_stop_reason_string): Use new enum unwind_stop_reason
	constants for bound-checking.
	* unwind_stop_reasons.def: New file.
	* stack.c (backtrace_command_1): Handle UNWIND_FIRST_ERROR as an alias
	instead of a distinct value.

doc/
	* gdb.texinfo ((Frames In Python): Document
	gdb.FRAME_UNWIND_FIRST_ERROR contant.
2011-10-27 11:04:27 +00:00