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 Merge changes from GCC for the config/ directory 2020-02-19 17:51:24 +00:00
contrib contrib: Update dg-extract-results.* from gcc 2019-10-21 15:26:48 +01:00
cpu cpu,gas,opcodes: support for eBPF JMP32 instruction class 2020-04-16 09:52:57 +02:00
elfcpp Add markers for 2.34 branch to the NEWS files and ChangeLogs. 2020-01-18 13:50:25 +00:00
etc texi2pod.pl: import support for @t{...} from gcc 2020-01-15 12:58:09 -05:00
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 Merge config/ changes from GCC. 2018-10-31 17:16:41 +00:00
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 Fix compilation of Readline on mingw.org's MinGW 2019-12-23 16:28:32 +02:00
sim sim: ppc: netbsd: Sync signal names with NetBSD 9.99.49 2020-03-12 16:07:37 +01:00
texinfo
zlib Merge changes from GCC for the config/ directory 2020-02-19 17:51:24 +00:00
.cvsignore
.gitattributes
.gitignore Add profiling outputs to .gitignore 2019-12-26 06:54:58 +01:00
COPYING
COPYING.LIB
COPYING.LIBGLOSS
COPYING.NEWLIB
COPYING3
COPYING3.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
MAINTAINERS Move gdbserver to top level 2020-02-07 08:42:25 -07:00
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
Makefile.tpl Revert "Sync top level files with versions from gcc." 2019-05-30 11:17:19 +01:00
README
README-maintainer-mode Bump to autoconf 2.69 and automake 1.15.1 2018-06-19 16:55:06 -04:00
ar-lib Bump to autoconf 2.69 and automake 1.15.1 2018-06-19 16:55:06 -04:00
compile
config-ml.in Update top level configure files by synchronizing them with gcc. 2018-01-10 15:29:21 +00:00
config.guess Update top level config files with copies from the official repository. 2020-01-18 13:43:19 +00:00
config.rpath
config.sub Update top level config files with copies from the official repository. 2020-01-18 13:43:19 +00:00
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
depcomp
djunpack.bat
install-sh
libtool.m4 Bump to autoconf 2.69 and automake 1.15.1 2018-06-19 16:55:06 -04:00
ltgcc.m4
ltmain.sh
ltoptions.m4
ltsugar.m4
ltversion.m4
lt~obsolete.m4
makefile.vms
missing
mkdep
mkinstalldirs
move-if-change
multilib.am Merge autoconf / automake update changes from GCC. 2018-10-31 17:10:56 +00:00
setup.com
src-release.sh Move gdbserver to top level 2020-02-07 08:42:25 -07:00
symlink-tree
test-driver Bump to autoconf 2.69 and automake 1.15.1 2018-06-19 16:55:06 -04:00
ylwrap

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