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Binutils 2.38 ARC patches #4

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merged 1 commit into from
Jul 8, 2022

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Binutils 2.38 ARC patches

Cherry-picked from foss-for-synopsys-dwc-arc-processors/binutils-gdb
commit d8beb08cbdfcdf65994f2ae09d8fb550002e9dd8.

Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
@stephanosio stephanosio self-assigned this Jun 14, 2022
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To be merged as part of a separate ARC support PR on the sdk-ng side.

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@stephanosio stephanosio merged commit e5502bc into zephyr-binutils-2_38 Jul 8, 2022
@stephanosio stephanosio removed the DNM label Jul 8, 2022
@stephanosio stephanosio deleted the zephyr-binutils-2_38_arc branch July 8, 2022 05:44
alpsayin pushed a commit to alpsayin/binutils-gdb that referenced this pull request Apr 29, 2023
Fedora Rawhide is now using gcc-12.0.  As part of updating to the
gcc-12.0 package set, Rawhide is also now using a version of libgcc_s
which lacks a .data section.  This causes gdb to fail in the following
fashion while debugging a program (such as gdb) which uses libgcc_s:

    (top-gdb) run
    Starting program: rawhide-master/bld/gdb/gdb
    ...
    objfiles.h:467: internal-error: sect_index_data not initialized
    A problem internal to GDB has been detected,
    further debugging may prove unreliable.
    ...

I snipped the backtrace from the above output.  Instead, here's a
portion of a backtrace obtained using GDB's backtrace command.
(Obviously, in order to obtain it, I used a GDB which has been patched
with this commit.)

    #0  internal_error (
	file=0xc6a508 "gdb/objfiles.h", line=467,
	fmt=0xc6a4e8 "sect_index_data not initialized")
	at gdbsupport/errors.cc:51
    zephyrproject-rtos#1  0x00000000005f9651 in objfile::data_section_offset (this=0x4fa48f0)
	at gdb/objfiles.h:467
    zephyrproject-rtos#2  0x000000000097c5f8 in relocate_address (address=0x17244, objfile=0x4fa48f0)
	at gdb/stap-probe.c:1333
    zephyrproject-rtos#3  0x000000000097c630 in stap_probe::get_relocated_address (this=0xa1a17a0,
	objfile=0x4fa48f0)
	at gdb/stap-probe.c:1341
    zephyrproject-rtos#4  0x00000000004d7025 in create_exception_master_breakpoint_probe (
	objfile=0x4fa48f0)
	at gdb/breakpoint.c:3505
    zephyrproject-rtos#5  0x00000000004d7426 in create_exception_master_breakpoint ()
	at gdb/breakpoint.c:3575
    zephyrproject-rtos#6  0x00000000004efcc1 in breakpoint_re_set ()
	at gdb/breakpoint.c:13407
    zephyrproject-rtos#7  0x0000000000956998 in solib_add (pattern=0x0, from_tty=0, readsyms=1)
	at gdb/solib.c:1001
    zephyrproject-rtos#8  0x00000000009576a8 in handle_solib_event ()
	at gdb/solib.c:1269
    ...

The function 'relocate_address' in gdb/stap-probe.c attempts to do
its "relocation" by using objfile->data_section_offset().  That
method, data_section_offset() is defined as follows in objfiles.h:

  CORE_ADDR data_section_offset () const
  {
    return section_offsets[SECT_OFF_DATA (this)];
  }

The internal error occurs when the SECT_OFF_DATA macro finds that the
'sect_index_data' field is -1:

    #define SECT_OFF_DATA(objfile) \
	 ((objfile->sect_index_data == -1) \
	  ? (internal_error (__FILE__, __LINE__, \
			     _("sect_index_data not initialized")), -1)	\
	  : objfile->sect_index_data)

relocate_address() is obtaining the section offset in order to compute
a relocated address.  For some ABIs, such as the System V ABI, the
section offsets will all be the same.  So for those ABIs, it doesn't
matter which offset is used.  However, other ABIs, such as the FDPIC
ABI, will have different offsets for the various sections.  Thus, for
those ABIs, it is vital that this and other relocation code use the
correct offset.

In stap_probe::get_relocated_address, the address to which to add the
offset (thus forming the relocated address) is obtained via
this->get_address (); get_address is a getter for m_address in
probe.h.  It's documented/defined as follows (also in probe.h):

  /* The address where the probe is inserted, relative to
     SECT_OFF_TEXT.  */
  CORE_ADDR m_address;

(Thanks to Tom Tromey for this observation.)

So, based on this, the current use of data_section_offset /
SECT_OFF_DATA is wrong.  This relocation code should have been using
text_section_offset / SECT_OFF_TEXT all along.  That being the
case, I've adjusted the stap-probe.c relocation code accordingly.

Searching the sources turned up one other use of data_section_offset,
in gdb/dtrace-probe.c, so I've updated that code as well.  The same
reasoning presented above applies to this case too.

Summary:

	* gdb/dtrace-probe.c (dtrace_probe::get_relocated_address):
	Use method text_section_offset instead of data_section_offset.
	* gdb/stap-probe.c (relocate_address): Likewise.
alpsayin pushed a commit to alpsayin/binutils-gdb that referenced this pull request Apr 29, 2023
g++ 11.1.0 has a bug where it will emit a negative
DW_AT_data_member_location in some cases:

    $ cat test.cpp
    #include <memory>

    int
    main()
    {
      std::unique_ptr<int> ptr;
    }
    $ g++ -g test.cpp
    $ llvm-dwarfdump -F a.out
    ...
    0x00000964:       DW_TAG_member
                        DW_AT_name [DW_FORM_strp]   ("_M_head_impl")
                        DW_AT_decl_file [DW_FORM_data1]     ("/usr/include/c++/11.1.0/tuple")
                        DW_AT_decl_line [DW_FORM_data1]     (125)
                        DW_AT_decl_column [DW_FORM_data1]   (0x27)
                        DW_AT_type [DW_FORM_ref4]   (0x0000067a "default_delete<int>")
                        DW_AT_data_member_location [DW_FORM_sdata]  (-1)
    ...

This leads to a GDB crash (when built with ASan, otherwise probably
garbage results), since it tries to read just before (to the left, in
ASan speak) of the value's buffer:

    ==888645==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x6020000c52af at pc 0x7f711b239f4b bp 0x7fff356bd470 sp 0x7fff356bcc18
    READ of size 1 at 0x6020000c52af thread T0
        #0 0x7f711b239f4a in __interceptor_memcpy /build/gcc/src/gcc/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:827
        zephyrproject-rtos#1 0x555c4977efa1 in value_contents_copy_raw /home/simark/src/binutils-gdb/gdb/value.c:1347
        zephyrproject-rtos#2 0x555c497909cd in value_primitive_field(value*, long, int, type*) /home/simark/src/binutils-gdb/gdb/value.c:3126
        zephyrproject-rtos#3 0x555c478f2eaa in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:333
        zephyrproject-rtos#4 0x555c478f63b2 in cp_print_value /home/simark/src/binutils-gdb/gdb/cp-valprint.c:513
        zephyrproject-rtos#5 0x555c478f02ca in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:161
        zephyrproject-rtos#6 0x555c478f63b2 in cp_print_value /home/simark/src/binutils-gdb/gdb/cp-valprint.c:513
        zephyrproject-rtos#7 0x555c478f02ca in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:161
        zephyrproject-rtos#8 0x555c478f63b2 in cp_print_value /home/simark/src/binutils-gdb/gdb/cp-valprint.c:513
        zephyrproject-rtos#9 0x555c478f02ca in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:161
        zephyrproject-rtos#10 0x555c4760d45f in c_value_print_struct /home/simark/src/binutils-gdb/gdb/c-valprint.c:383
        zephyrproject-rtos#11 0x555c4760df4c in c_value_print_inner(value*, ui_file*, int, value_print_options const*) /home/simark/src/binutils-gdb/gdb/c-valprint.c:438
        zephyrproject-rtos#12 0x555c483ff9a7 in language_defn::value_print_inner(value*, ui_file*, int, value_print_options const*) const /home/simark/src/binutils-gdb/gdb/language.c:632
        zephyrproject-rtos#13 0x555c49758b68 in do_val_print /home/simark/src/binutils-gdb/gdb/valprint.c:1048
        zephyrproject-rtos#14 0x555c49759b17 in common_val_print(value*, ui_file*, int, value_print_options const*, language_defn const*) /home/simark/src/binutils-gdb/gdb/valprint.c:1151
        #15 0x555c478f2fcb in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:335
        #16 0x555c478f63b2 in cp_print_value /home/simark/src/binutils-gdb/gdb/cp-valprint.c:513
        #17 0x555c478f02ca in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:161
        #18 0x555c4760d45f in c_value_print_struct /home/simark/src/binutils-gdb/gdb/c-valprint.c:383
        #19 0x555c4760df4c in c_value_print_inner(value*, ui_file*, int, value_print_options const*) /home/simark/src/binutils-gdb/gdb/c-valprint.c:438
        #20 0x555c483ff9a7 in language_defn::value_print_inner(value*, ui_file*, int, value_print_options const*) const /home/simark/src/binutils-gdb/gdb/language.c:632
        #21 0x555c49758b68 in do_val_print /home/simark/src/binutils-gdb/gdb/valprint.c:1048
        #22 0x555c49759b17 in common_val_print(value*, ui_file*, int, value_print_options const*, language_defn const*) /home/simark/src/binutils-gdb/gdb/valprint.c:1151
        #23 0x555c478f2fcb in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:335
        #24 0x555c4760d45f in c_value_print_struct /home/simark/src/binutils-gdb/gdb/c-valprint.c:383
        #25 0x555c4760df4c in c_value_print_inner(value*, ui_file*, int, value_print_options const*) /home/simark/src/binutils-gdb/gdb/c-valprint.c:438
        #26 0x555c483ff9a7 in language_defn::value_print_inner(value*, ui_file*, int, value_print_options const*) const /home/simark/src/binutils-gdb/gdb/language.c:632
        #27 0x555c49758b68 in do_val_print /home/simark/src/binutils-gdb/gdb/valprint.c:1048
        #28 0x555c49759b17 in common_val_print(value*, ui_file*, int, value_print_options const*, language_defn const*) /home/simark/src/binutils-gdb/gdb/valprint.c:1151
        #29 0x555c4760f04c in c_value_print(value*, ui_file*, value_print_options const*) /home/simark/src/binutils-gdb/gdb/c-valprint.c:587
        #30 0x555c483ff954 in language_defn::value_print(value*, ui_file*, value_print_options const*) const /home/simark/src/binutils-gdb/gdb/language.c:614
        #31 0x555c49759f61 in value_print(value*, ui_file*, value_print_options const*) /home/simark/src/binutils-gdb/gdb/valprint.c:1189
        #32 0x555c48950f70 in print_formatted /home/simark/src/binutils-gdb/gdb/printcmd.c:337
        #33 0x555c48958eda in print_value(value*, value_print_options const&) /home/simark/src/binutils-gdb/gdb/printcmd.c:1258
        #34 0x555c48959891 in print_command_1 /home/simark/src/binutils-gdb/gdb/printcmd.c:1367
        #35 0x555c4895a3df in print_command /home/simark/src/binutils-gdb/gdb/printcmd.c:1458
        #36 0x555c4767f974 in do_simple_func /home/simark/src/binutils-gdb/gdb/cli/cli-decode.c:97
        #37 0x555c47692e25 in cmd_func(cmd_list_element*, char const*, int) /home/simark/src/binutils-gdb/gdb/cli/cli-decode.c:2475
        #38 0x555c4936107e in execute_command(char const*, int) /home/simark/src/binutils-gdb/gdb/top.c:670
        #39 0x555c485f1bff in catch_command_errors /home/simark/src/binutils-gdb/gdb/main.c:523
        #40 0x555c485f249c in execute_cmdargs /home/simark/src/binutils-gdb/gdb/main.c:618
        #41 0x555c485f6677 in captured_main_1 /home/simark/src/binutils-gdb/gdb/main.c:1317
        #42 0x555c485f6c83 in captured_main /home/simark/src/binutils-gdb/gdb/main.c:1338
        #43 0x555c485f6d65 in gdb_main(captured_main_args*) /home/simark/src/binutils-gdb/gdb/main.c:1363
        #44 0x555c46e41ba8 in main /home/simark/src/binutils-gdb/gdb/gdb.c:32
        #45 0x7f71198bcb24 in __libc_start_main (/usr/lib/libc.so.6+0x27b24)
        #46 0x555c46e4197d in _start (/home/simark/build/binutils-gdb-one-target/gdb/gdb+0x77f197d)

    0x6020000c52af is located 1 bytes to the left of 8-byte region [0x6020000c52b0,0x6020000c52b8)
    allocated by thread T0 here:
        #0 0x7f711b2b7459 in __interceptor_calloc /build/gcc/src/gcc/libsanitizer/asan/asan_malloc_linux.cpp:154
        zephyrproject-rtos#1 0x555c470acdc9 in xcalloc /home/simark/src/binutils-gdb/gdb/alloc.c:100
        zephyrproject-rtos#2 0x555c49b775cd in xzalloc(unsigned long) /home/simark/src/binutils-gdb/gdbsupport/common-utils.cc:29
        zephyrproject-rtos#3 0x555c4977bdeb in allocate_value_contents /home/simark/src/binutils-gdb/gdb/value.c:1029
        zephyrproject-rtos#4 0x555c4977be25 in allocate_value(type*) /home/simark/src/binutils-gdb/gdb/value.c:1040
        zephyrproject-rtos#5 0x555c4979030d in value_primitive_field(value*, long, int, type*) /home/simark/src/binutils-gdb/gdb/value.c:3092
        zephyrproject-rtos#6 0x555c478f6280 in cp_print_value /home/simark/src/binutils-gdb/gdb/cp-valprint.c:501
        zephyrproject-rtos#7 0x555c478f02ca in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:161
        zephyrproject-rtos#8 0x555c478f63b2 in cp_print_value /home/simark/src/binutils-gdb/gdb/cp-valprint.c:513
        zephyrproject-rtos#9 0x555c478f02ca in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:161
        zephyrproject-rtos#10 0x555c478f63b2 in cp_print_value /home/simark/src/binutils-gdb/gdb/cp-valprint.c:513
        zephyrproject-rtos#11 0x555c478f02ca in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:161
        zephyrproject-rtos#12 0x555c4760d45f in c_value_print_struct /home/simark/src/binutils-gdb/gdb/c-valprint.c:383
        zephyrproject-rtos#13 0x555c4760df4c in c_value_print_inner(value*, ui_file*, int, value_print_options const*) /home/simark/src/binutils-gdb/gdb/c-valprint.c:438
        zephyrproject-rtos#14 0x555c483ff9a7 in language_defn::value_print_inner(value*, ui_file*, int, value_print_options const*) const /home/simark/src/binutils-gdb/gdb/language.c:632
        #15 0x555c49758b68 in do_val_print /home/simark/src/binutils-gdb/gdb/valprint.c:1048
        #16 0x555c49759b17 in common_val_print(value*, ui_file*, int, value_print_options const*, language_defn const*) /home/simark/src/binutils-gdb/gdb/valprint.c:1151
        #17 0x555c478f2fcb in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:335
        #18 0x555c478f63b2 in cp_print_value /home/simark/src/binutils-gdb/gdb/cp-valprint.c:513
        #19 0x555c478f02ca in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:161
        #20 0x555c4760d45f in c_value_print_struct /home/simark/src/binutils-gdb/gdb/c-valprint.c:383
        #21 0x555c4760df4c in c_value_print_inner(value*, ui_file*, int, value_print_options const*) /home/simark/src/binutils-gdb/gdb/c-valprint.c:438
        #22 0x555c483ff9a7 in language_defn::value_print_inner(value*, ui_file*, int, value_print_options const*) const /home/simark/src/binutils-gdb/gdb/language.c:632
        #23 0x555c49758b68 in do_val_print /home/simark/src/binutils-gdb/gdb/valprint.c:1048
        #24 0x555c49759b17 in common_val_print(value*, ui_file*, int, value_print_options const*, language_defn const*) /home/simark/src/binutils-gdb/gdb/valprint.c:1151
        #25 0x555c478f2fcb in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:335
        #26 0x555c4760d45f in c_value_print_struct /home/simark/src/binutils-gdb/gdb/c-valprint.c:383
        #27 0x555c4760df4c in c_value_print_inner(value*, ui_file*, int, value_print_options const*) /home/simark/src/binutils-gdb/gdb/c-valprint.c:438
        #28 0x555c483ff9a7 in language_defn::value_print_inner(value*, ui_file*, int, value_print_options const*) const /home/simark/src/binutils-gdb/gdb/language.c:632
        #29 0x555c49758b68 in do_val_print /home/simark/src/binutils-gdb/gdb/valprint.c:1048

Since there are some binaries with this in the wild, I think it would be
useful for GDB to work around this.  I did the obvious simple thing, if
the DW_AT_data_member_location's value is -1, replace it with 0.  I
added a producer check to only apply this fixup for GCC 11.  The idea is
that if some other compiler ever uses a DW_AT_data_member_location value
of -1 by mistake, we don't know (before analyzing the bug at least) if
they did mean 0 or some other value.  So I wouldn't want to apply the
fixup in that case.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=28063
Change-Id: Ieef3459b0b9bbce8bdad838ba83b4b64e7269d42
alpsayin pushed a commit to alpsayin/binutils-gdb that referenced this pull request Apr 29, 2023
Starting with commit

  commit 1da5d0e
  Date:   Tue Jan 4 08:02:24 2022 -0700

    Change how Python architecture and language are handled

we see a failure in gdb.threads/killed-outside.exp:

  ...
  Executing on target: kill -9 16622    (timeout = 300)
  builtin_spawn -ignore SIGHUP kill -9 16622
  continue
  Continuing.
  Couldn't get registers: No such process.
  (gdb) [Thread 0x7ffff77c2700 (LWP 16626) exited]

  Program terminated with signal SIGKILL, Killed.
  The program no longer exists.
  FAIL: gdb.threads/killed-outside.exp: prompt after first continue (timeout)

This is not a regression but a failure due to a change in GDB's
output.  Prior to the aforementioned commit, GDB has been printing the
"Couldn't get registers: No such process." message twice.  The second
one came from

  (top-gdb) bt
  #0  amd64_linux_nat_target::fetch_registers (this=0x555557f31440 <the_amd64_linux_nat_target>, regcache=0x555558805ce0, regnum=16) at /gdb-up/gdb/amd64-linux-nat.c:225
  zephyrproject-rtos#1  0x000055555640ac5f in target_ops::fetch_registers (this=0x555557d636d0 <the_thread_db_target>, arg0=0x555558805ce0, arg1=16) at /gdb-up/gdb/target-delegates.c:502
  zephyrproject-rtos#2  0x000055555641a647 in target_fetch_registers (regcache=0x555558805ce0, regno=16) at /gdb-up/gdb/target.c:3945
  zephyrproject-rtos#3  0x0000555556278e68 in regcache::raw_update (this=0x555558805ce0, regnum=16) at /gdb-up/gdb/regcache.c:587
  zephyrproject-rtos#4  0x0000555556278f14 in readable_regcache::raw_read (this=0x555558805ce0, regnum=16, buf=0x555558881950 "") at /gdb-up/gdb/regcache.c:601
  zephyrproject-rtos#5  0x00005555562792aa in readable_regcache::cooked_read (this=0x555558805ce0, regnum=16, buf=0x555558881950 "") at /gdb-up/gdb/regcache.c:690
  zephyrproject-rtos#6  0x000055555627965e in readable_regcache::cooked_read_value (this=0x555558805ce0, regnum=16) at /gdb-up/gdb/regcache.c:748
  zephyrproject-rtos#7  0x0000555556352a37 in sentinel_frame_prev_register (this_frame=0x555558181090, this_prologue_cache=0x5555581810a8, regnum=16) at /gdb-up/gdb/sentinel-frame.c:53
  zephyrproject-rtos#8  0x0000555555fa4773 in frame_unwind_register_value (next_frame=0x555558181090, regnum=16) at /gdb-up/gdb/frame.c:1235
  zephyrproject-rtos#9  0x0000555555fa420d in frame_register_unwind (next_frame=0x555558181090, regnum=16, optimizedp=0x7fffffffd570, unavailablep=0x7fffffffd574, lvalp=0x7fffffffd57c, addrp=0x7fffffffd580,
      realnump=0x7fffffffd578, bufferp=0x7fffffffd5b0 "") at /gdb-up/gdb/frame.c:1143
  zephyrproject-rtos#10 0x0000555555fa455f in frame_unwind_register (next_frame=0x555558181090, regnum=16, buf=0x7fffffffd5b0 "") at /gdb-up/gdb/frame.c:1199
  zephyrproject-rtos#11 0x00005555560178e2 in i386_unwind_pc (gdbarch=0x5555587c4a70, next_frame=0x555558181090) at /gdb-up/gdb/i386-tdep.c:1972
  zephyrproject-rtos#12 0x0000555555cd2b9d in gdbarch_unwind_pc (gdbarch=0x5555587c4a70, next_frame=0x555558181090) at /gdb-up/gdb/gdbarch.c:3007
  zephyrproject-rtos#13 0x0000555555fa3a5b in frame_unwind_pc (this_frame=0x555558181090) at /gdb-up/gdb/frame.c:948
  zephyrproject-rtos#14 0x0000555555fa7621 in get_frame_pc (frame=0x555558181160) at /gdb-up/gdb/frame.c:2572
  #15 0x0000555555fa7706 in get_frame_address_in_block (this_frame=0x555558181160) at /gdb-up/gdb/frame.c:2602
  #16 0x0000555555fa77d0 in get_frame_address_in_block_if_available (this_frame=0x555558181160, pc=0x7fffffffd708) at /gdb-up/gdb/frame.c:2665
  #17 0x0000555555fa5f8d in select_frame (fi=0x555558181160) at /gdb-up/gdb/frame.c:1890
  #18 0x0000555555fa5bab in lookup_selected_frame (a_frame_id=..., frame_level=-1) at /gdb-up/gdb/frame.c:1720
  #19 0x0000555555fa5e47 in get_selected_frame (message=0x0) at /gdb-up/gdb/frame.c:1810
  #20 0x0000555555cc9c6e in get_current_arch () at /gdb-up/gdb/arch-utils.c:848
  #21 0x000055555625b239 in gdbpy_before_prompt_hook (extlang=0x555557451f20 <extension_language_python>, current_gdb_prompt=0x555557f4d890 <top_prompt+16> "(gdb) ")
      at /gdb-up/gdb/python/python.c:1063
  #22 0x0000555555f7cfbb in ext_lang_before_prompt (current_gdb_prompt=0x555557f4d890 <top_prompt+16> "(gdb) ") at /gdb-up/gdb/extension.c:922
  #23 0x0000555555f7d442 in std::_Function_handler<void (char const*), void (*)(char const*)>::_M_invoke(std::_Any_data const&, char const*&&) (__functor=...,
      __args#0=@0x7fffffffd900: 0x555557f4d890 <top_prompt+16> "(gdb) ") at /usr/include/c++/7/bits/std_function.h:316
  #24 0x0000555555f752dd in std::function<void (char const*)>::operator()(char const*) const (this=0x55555817d838, __args#0=0x555557f4d890 <top_prompt+16> "(gdb) ")
      at /usr/include/c++/7/bits/std_function.h:706
  #25 0x0000555555f75100 in gdb::observers::observable<char const*>::notify (this=0x555557f49060 <gdb::observers::before_prompt>, args#0=0x555557f4d890 <top_prompt+16> "(gdb) ")
      at /gdb-up/gdb/../gdbsupport/observable.h:150
  #26 0x0000555555f736dc in top_level_prompt () at /gdb-up/gdb/event-top.c:444
  #27 0x0000555555f735ba in display_gdb_prompt (new_prompt=0x0) at /gdb-up/gdb/event-top.c:411
  #28 0x00005555564611a7 in tui_on_command_error () at /gdb-up/gdb/tui/tui-interp.c:205
  #29 0x0000555555c2173f in std::_Function_handler<void (), void (*)()>::_M_invoke(std::_Any_data const&) (__functor=...) at /usr/include/c++/7/bits/std_function.h:316
  #30 0x0000555555e10c20 in std::function<void ()>::operator()() const (this=0x5555580f9028) at /usr/include/c++/7/bits/std_function.h:706
  #31 0x0000555555e10973 in gdb::observers::observable<>::notify() const (this=0x555557f48d20 <gdb::observers::command_error>) at /gdb-up/gdb/../gdbsupport/observable.h:150
  #32 0x00005555560e9b3f in start_event_loop () at /gdb-up/gdb/main.c:438
  #33 0x00005555560e9bcc in captured_command_loop () at /gdb-up/gdb/main.c:481
  #34 0x00005555560eb616 in captured_main (data=0x7fffffffddd0) at /gdb-up/gdb/main.c:1348
  #35 0x00005555560eb67c in gdb_main (args=0x7fffffffddd0) at /gdb-up/gdb/main.c:1363
  #36 0x0000555555c1b6b3 in main (argc=12, argv=0x7fffffffded8) at /gdb-up/gdb/gdb.c:32

Commit 1da5d0e eliminated the call to 'get_current_arch'
in 'gdbpy_before_prompt_hook'.  Hence, the second instance of
"Couldn't get registers: No such process." does not appear anymore.

Fix the failure by updating the regular expression in the test.
alpsayin pushed a commit to alpsayin/binutils-gdb that referenced this pull request Apr 29, 2023
…ync."

Commit 14b3360 ("do_target_wait_1: Clear
TARGET_WNOHANG if the target isn't async.") broke some multi-target
tests, such as gdb.multi/multi-target-info-inferiors.exp.  The symptom
is that execution just hangs at some point.  What happens is:

1. One remote inferior is started, and now sits stopped at a breakpoint.
   It is not "async" at this point (but it "can async").

2. We run a native inferior, the event loop gets woken up by the native
   target's fd.

3. In do_target_wait, we randomly choose an inferior to call target_wait
   on first, it happens to be the remote inferior.

4. Because the target is currently not "async", we clear
   TARGET_WNOHANG, resulting in synchronous wait.  We therefore block
   here:

  #0  0x00007fe9540dbb4d in select () from /usr/lib/libc.so.6
  zephyrproject-rtos#1  0x000055fc7e821da7 in gdb_select (n=15, readfds=0x7ffdb77c1fb0, writefds=0x0, exceptfds=0x7ffdb77c2050, timeout=0x7ffdb77c1f90) at /home/simark/src/binutils-gdb/gdb/posix-hdep.c:31
  zephyrproject-rtos#2  0x000055fc7ddef905 in interruptible_select (n=15, readfds=0x7ffdb77c1fb0, writefds=0x0, exceptfds=0x7ffdb77c2050, timeout=0x7ffdb77c1f90) at /home/simark/src/binutils-gdb/gdb/event-top.c:1134
  zephyrproject-rtos#3  0x000055fc7eda58e4 in ser_base_wait_for (scb=0x6250002e4100, timeout=1) at /home/simark/src/binutils-gdb/gdb/ser-base.c:240
  zephyrproject-rtos#4  0x000055fc7eda66ba in do_ser_base_readchar (scb=0x6250002e4100, timeout=-1) at /home/simark/src/binutils-gdb/gdb/ser-base.c:365
  zephyrproject-rtos#5  0x000055fc7eda6ff6 in generic_readchar (scb=0x6250002e4100, timeout=-1, do_readchar=0x55fc7eda663c <do_ser_base_readchar(serial*, int)>) at /home/simark/src/binutils-gdb/gdb/ser-base.c:444
  zephyrproject-rtos#6  0x000055fc7eda718a in ser_base_readchar (scb=0x6250002e4100, timeout=-1) at /home/simark/src/binutils-gdb/gdb/ser-base.c:471
  zephyrproject-rtos#7  0x000055fc7edb1ecd in serial_readchar (scb=0x6250002e4100, timeout=-1) at /home/simark/src/binutils-gdb/gdb/serial.c:393
  zephyrproject-rtos#8  0x000055fc7ec48b8f in remote_target::readchar (this=0x617000038780, timeout=-1) at /home/simark/src/binutils-gdb/gdb/remote.c:9446
  zephyrproject-rtos#9  0x000055fc7ec4da82 in remote_target::getpkt_or_notif_sane_1 (this=0x617000038780, buf=0x6170000387a8, forever=1, expecting_notif=1, is_notif=0x7ffdb77c24f0) at /home/simark/src/binutils-gdb/gdb/remote.c:9928
  zephyrproject-rtos#10 0x000055fc7ec4f045 in remote_target::getpkt_or_notif_sane (this=0x617000038780, buf=0x6170000387a8, forever=1, is_notif=0x7ffdb77c24f0) at /home/simark/src/binutils-gdb/gdb/remote.c:10037
  zephyrproject-rtos#11 0x000055fc7ec354d4 in remote_target::wait_ns (this=0x617000038780, ptid=..., status=0x7ffdb77c33c8, options=...) at /home/simark/src/binutils-gdb/gdb/remote.c:8147
  zephyrproject-rtos#12 0x000055fc7ec38aa1 in remote_target::wait (this=0x617000038780, ptid=..., status=0x7ffdb77c33c8, options=...) at /home/simark/src/binutils-gdb/gdb/remote.c:8337
  zephyrproject-rtos#13 0x000055fc7f1409ce in target_wait (ptid=..., status=0x7ffdb77c33c8, options=...) at /home/simark/src/binutils-gdb/gdb/target.c:2612
  zephyrproject-rtos#14 0x000055fc7e19da98 in do_target_wait_1 (inf=0x617000038080, ptid=..., status=0x7ffdb77c33c8, options=...) at /home/simark/src/binutils-gdb/gdb/infrun.c:3636
  #15 0x000055fc7e19e26b in operator() (__closure=0x7ffdb77c2f90, inf=0x617000038080) at /home/simark/src/binutils-gdb/gdb/infrun.c:3697
  #16 0x000055fc7e19f0c4 in do_target_wait (ecs=0x7ffdb77c33a0, options=...) at /home/simark/src/binutils-gdb/gdb/infrun.c:3716
  #17 0x000055fc7e1a31f7 in fetch_inferior_event () at /home/simark/src/binutils-gdb/gdb/infrun.c:4061

Before the aforementioned commit, we would not have cleared
TARGET_WNOHANG, the remote target's wait would have returned nothing,
and we would have consumed the native target's event.

After applying this revert, the testsuite state looks as good as before
for me on Ubuntu 20.04 amd64.

Change-Id: Ic17a1642935cabcc16c25cb6899d52e12c2f5c3f
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