Binutils with MCST patches
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Tankut Baris Aktemur d43b7a2d57 gdb/infrun: switch the context before 'displaced_step_restore'
In infrun.c's 'displaced_step_fixup', as part of the 'finish_step_over'
flow, switch to the eventing thread *before* calling
'displaced_step_restore', because down in the flow ptid-dependent
memory accesses are used via current_inferior() and current_top_target().

Without this patch, the problem is exposed with the scenario below:

   $ gdb -q
   (gdb) maint set target-non-stop on
   (gdb) file a.out
   Reading symbols from a.out...
   (gdb) set remote exec-file a.out
   (gdb) target extended-remote | gdbserver --once --multi -
   ...
   (gdb) add-inferior
   [New inferior 2]
   Added inferior 2 on connection 1 (extended-remote ...)
   (gdb) inferior 2
   [Switching to inferior 2 [<null>] (<noexec>)]
   (gdb) file a.out
   Reading symbols from a.out...
   (gdb) set remote exec-file a.out
   (gdb) run
   ...
   Cannot access memory at address 0x555555555042
   (gdb)

The problem is, down inside 'displaced_step_restore', GDB wants to
access the memory for inferior 2 because of an internal breakpoint.
However, the current inferior and inferior_ptid are out of sync.
While inferior_ptid correctly points to the process of inf 2 that was
just started, current_inferior points to inf 1.  Then, the attempt to
access the memory fails, because target_has_execution results in false
since inf 1 was not started.  I was not able to simplify the failing
scenario, but it shows the problem.

After this patch, we get

  ... same steps above...
  (gdb) run
  ...
  [Inferior 2 (process 28652) exited normally]
  (gdb)

Regression-tested on X86_64 Linux with `make check`s default board file
and also `--target_board=native-extended-gdbserver`.  In fact, the bug
fixed by this patch was exposed when using the native-extended-gdbserver
board file.

gdb/ChangeLog:
2020-04-21  Tankut Baris Aktemur  <tankut.baris.aktemur@intel.com>

	* infrun.c (displaced_step_fixup): Switch to the event_thread
	before calling displaced_step_restore, not after.

gdb/testsuite/ChangeLog:
2020-04-21  Tankut Baris Aktemur  <tankut.baris.aktemur@intel.com>

	* gdb.multi/run-only-second-inf.c: New file.
	* gdb.multi/run-only-second-inf.exp: New file.
2020-04-21 17:24:03 +02:00
bfd BFD: Exclude sections with no content from compress check. 2020-04-21 15:17:18 +01:00
binutils fix typo last commit 2020-04-20 12:01:47 +09:30
config
contrib
cpu cpu,gas,opcodes: support for eBPF JMP32 instruction class 2020-04-16 09:52:57 +02:00
elfcpp
etc
gas Disallow PC relative for CMPI on MC68000/10 2020-04-21 16:53:36 +02:00
gdb gdb/infrun: switch the context before 'displaced_step_restore' 2020-04-21 17:24:03 +02:00
gdbserver Fix Cygwin gdb build 2020-04-16 07:24:57 -06:00
gdbsupport Mark move constructors as "noexcept" 2020-04-20 11:45:06 -06:00
gnulib gdb: update gnulib import 2020-02-22 20:37:18 -05:00
gold Add support for --no-rosegment option. 2020-03-19 15:54:38 -07:00
gprof Updated Serbian translation for the gprof subdirectory 2020-04-01 14:37:02 +01:00
include Remove SH-5 remnants 2020-04-21 11:35:43 +09:30
intl Regen with blessed automake-1.15.1 2020-02-20 13:02:24 +10:30
ld Fix linker tests to work with 16-bit targets. 2020-04-21 15:10:52 +01:00
libctf libctf: Mark bswap_identity_64 inline function as static. 2020-03-11 17:48:49 +10:30
libdecnumber
libiberty Import latest fixes to libiberty from GCC 2020-03-02 03:56:36 -08:00
opcodes Disallow PC relative for CMPI on MC68000/10 2020-04-21 16:53:36 +02:00
readline
sim sim: ppc: netbsd: Sync signal names with NetBSD 9.99.49 2020-03-12 16:07:37 +01:00
texinfo
zlib
.cvsignore
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ar-lib
ChangeLog Since the pdp11-aout target does not support gdb, gdbserver or gprof these should be excluded in configure. 2020-04-21 10:27:50 +01:00
compile
config-ml.in
config.guess
config.rpath
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configure Since the pdp11-aout target does not support gdb, gdbserver or gprof these should be excluded in configure. 2020-04-21 10:27:50 +01:00
configure.ac Since the pdp11-aout target does not support gdb, gdbserver or gprof these should be excluded in configure. 2020-04-21 10:27:50 +01:00
COPYING
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MAINTAINERS
Makefile.def Change gdbserver to use existing gdbsupport 2020-03-12 13:32:16 -06:00
Makefile.in Change gdbserver to use existing gdbsupport 2020-03-12 13:32:16 -06:00
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		   README for GNU development tools

This directory contains various GNU compilers, assemblers, linkers, 
debuggers, etc., plus their support routines, definitions, and documentation.

If you are receiving this as part of a GDB release, see the file gdb/README.
If with a binutils release, see binutils/README;  if with a libg++ release,
see libg++/README, etc.  That'll give you info about this
package -- supported targets, how to use it, how to report bugs, etc.

It is now possible to automatically configure and build a variety of
tools with one command.  To build all of the tools contained herein,
run the ``configure'' script here, e.g.:

	./configure 
	make

To install them (by default in /usr/local/bin, /usr/local/lib, etc),
then do:
	make install

(If the configure script can't determine your type of computer, give it
the name as an argument, for instance ``./configure sun4''.  You can
use the script ``config.sub'' to test whether a name is recognized; if
it is, config.sub translates it to a triplet specifying CPU, vendor,
and OS.)

If you have more than one compiler on your system, it is often best to
explicitly set CC in the environment before running configure, and to
also set CC when running make.  For example (assuming sh/bash/ksh):

	CC=gcc ./configure
	make

A similar example using csh:

	setenv CC gcc
	./configure
	make

Much of the code and documentation enclosed is copyright by
the Free Software Foundation, Inc.  See the file COPYING or
COPYING.LIB in the various directories, for a description of the
GNU General Public License terms under which you can copy the files.

REPORTING BUGS: Again, see gdb/README, binutils/README, etc., for info
on where and how to report problems.