Remove dbx mode

This patch removes gdb's dbx mode.  Regression tested on x86-64 Fedora
34.

gdb/NEWS

@@ -8,6 +8,8 @@
 * Remove support for building against Python 2, it is now only possible to
   build GDB against Python 3.
 
+* DBX mode has been removed.
+
 * Python API
 
   ** New function gdb.format_address(ADDRESS, PROGSPACE, ARCHITECTURE),

gdb/breakpoint.c

@@ -9296,79 +9296,6 @@ thbreak_command (const char *arg, int from_tty)
   break_command_1 (arg, (BP_TEMPFLAG | BP_HARDWAREFLAG), from_tty);
 }
 
-static void
-stop_command (const char *arg, int from_tty)
-{
-  gdb_printf (_("Specify the type of breakpoint to set.\n\
-Usage: stop in <function | address>\n\
-       stop at <line>\n"));
-}
-
-static void
-stopin_command (const char *arg, int from_tty)
-{
-  int badInput = 0;
-
-  if (arg == NULL)
-    badInput = 1;
-  else if (*arg != '*')
-    {
-      const char *argptr = arg;
-      int hasColon = 0;
-
-      /* Look for a ':'.  If this is a line number specification, then
-	 say it is bad, otherwise, it should be an address or
-	 function/method name.  */
-      while (*argptr && !hasColon)
-	{
-	  hasColon = (*argptr == ':');
-	  argptr++;
-	}
-
-      if (hasColon)
-	badInput = (*argptr != ':');	/* Not a class::method */
-      else
-	badInput = isdigit (*arg);	/* a simple line number */
-    }
-
-  if (badInput)
-    gdb_printf (_("Usage: stop in <function | address>\n"));
-  else
-    break_command_1 (arg, 0, from_tty);
-}
-
-static void
-stopat_command (const char *arg, int from_tty)
-{
-  int badInput = 0;
-
-  if (arg == NULL || *arg == '*')	/* no line number */
-    badInput = 1;
-  else
-    {
-      const char *argptr = arg;
-      int hasColon = 0;
-
-      /* Look for a ':'.  If there is a '::' then get out, otherwise
-	 it is probably a line number.  */
-      while (*argptr && !hasColon)
-	{
-	  hasColon = (*argptr == ':');
-	  argptr++;
-	}
-
-      if (hasColon)
-	badInput = (*argptr == ':');	/* we have class::method */
-      else
-	badInput = !isdigit (*arg);	/* not a line number */
-    }
-
-  if (badInput)
-    gdb_printf (_("Usage: stop at LINE\n"));
-  else
-    break_command_1 (arg, 0, from_tty);
-}
-
 /* The dynamic printf command is mostly like a regular breakpoint, but
    with a prewired command list consisting of a single output command,
    built from extra arguments supplied on the dprintf command
@@ -15105,32 +15032,6 @@ BREAK_ARGS_HELP ("break")));
   add_com_alias ("bre", break_cmd, class_run, 1);
   add_com_alias ("brea", break_cmd, class_run, 1);
 
-  if (dbx_commands)
-    {
-      add_abbrev_prefix_cmd ("stop", class_breakpoint, stop_command, _("\
-Break in function/address or break at a line in the current file."),
-			     &stoplist, 1, &cmdlist);
-      add_cmd ("in", class_breakpoint, stopin_command,
-	       _("Break in function or address."), &stoplist);
-      add_cmd ("at", class_breakpoint, stopat_command,
-	       _("Break at a line in the current file."), &stoplist);
-      add_com ("status", class_info, info_breakpoints_command, _("\
-Status of user-settable breakpoints, or breakpoint number NUMBER.\n\
-The \"Type\" column indicates one of:\n\
-\tbreakpoint     - normal breakpoint\n\
-\twatchpoint     - watchpoint\n\
-The \"Disp\" column contains one of \"keep\", \"del\", or \"dis\" to indicate\n\
-the disposition of the breakpoint after it gets hit.  \"dis\" means that the\n\
-breakpoint will be disabled.  The \"Address\" and \"What\" columns indicate the\n\
-address and file/line number respectively.\n\
-\n\
-Convenience variable \"$_\" and default examine address for \"x\"\n\
-are set to the address of the last breakpoint listed unless the command\n\
-is prefixed with \"server \".\n\n\
-Convenience variable \"$bpnum\" contains the number of the last\n\
-breakpoint set."));
-    }
-
   cmd_list_element *info_breakpoints_cmd
     = add_info ("breakpoints", info_breakpoints_command, _("\
 Status of specified breakpoints (all user-settable breakpoints if no argument).\n\

gdb/cli/cli-cmds.c

@@ -2421,8 +2421,7 @@ User-defined commands.\n\
 The commands in this class are those defined by the user.\n\
 Use the \"define\" command to define a command."), &cmdlist);
   add_cmd ("support", class_support, _("Support facilities."), &cmdlist);
-  if (!dbx_commands)
+  add_cmd ("status", class_info, _("Status inquiries."), &cmdlist);
-    add_cmd ("status", class_info, _("Status inquiries."), &cmdlist);
   add_cmd ("files", class_files, _("Specifying and examining files."),
 	   &cmdlist);
   add_cmd ("breakpoints", class_breakpoint,
@@ -2667,9 +2666,6 @@ can be shown using \"show listsize\"."));
 
   add_com_alias ("l", list_cmd, class_files, 1);
 
-  if (dbx_commands)
-    add_com_alias ("file", list_cmd, class_files, 1);
-
   c = add_com ("disassemble", class_vars, disassemble_command, _("\
 Disassemble a specified section of memory.\n\
 Usage: disassemble[/m|/r|/s] START [, END]\n\

gdb/defs.h

@@ -118,9 +118,6 @@ using RequireLongest = gdb::Requires<gdb::Or<std::is_same<T, LONGEST>,
 
 #include "hashtab.h"
 
-/* * Enable dbx commands if set.  */
-extern int dbx_commands;
-
 /* * System root path, used to find libraries etc.  */
 extern std::string gdb_sysroot;
 

gdb/doc/gdb.texinfo

@@ -47713,9 +47713,6 @@ Read all symbols from the given symfile on the first access.
 @item --readnever
 Do not read symbol files.
 
-@item --dbx
-Run in DBX compatibility mode.
-
 @item --return-child-result
 @value{GDBN}'s exit code will be the same as the child's exit code.
 

gdb/exec.c

@@ -1060,17 +1060,14 @@ _initialize_exec ()
 {
   struct cmd_list_element *c;
 
-  if (!dbx_commands)
+  c = add_cmd ("file", class_files, file_command, _("\
-    {
-      c = add_cmd ("file", class_files, file_command, _("\
 Use FILE as program to be debugged.\n\
 It is read for its symbols, for getting the contents of pure memory,\n\
 and it is the program executed when you use the `run' command.\n\
 If FILE cannot be found as specified, your execution directory path\n\
 ($PATH) is searched for a command of that name.\n\
 No arg means to have no executable file and no symbols."), &cmdlist);
-      set_cmd_completer (c, filename_completer);
+  set_cmd_completer (c, filename_completer);
-    }
 
   c = add_cmd ("exec-file", class_files, exec_file_command, _("\
 Use FILE as program for getting contents of pure memory.\n\

gdb/infrun.c

@@ -8564,28 +8564,25 @@ normal_stop (void)
 
   /* Look up the hook_stop and run it (CLI internally handles problem
      of stop_command's pre-hook not existing).  */
-  if (stop_command != NULL)
+  stop_context saved_context;
+
+  try
     {
-      stop_context saved_context;
+      execute_cmd_pre_hook (stop_command);
-
-      try
-	{
-	  execute_cmd_pre_hook (stop_command);
-	}
-      catch (const gdb_exception &ex)
-	{
-	  exception_fprintf (gdb_stderr, ex,
-			     "Error while running hook_stop:\n");
-	}
-
-      /* If the stop hook resumes the target, then there's no point in
-	 trying to notify about the previous stop; its context is
-	 gone.  Likewise if the command switches thread or inferior --
-	 the observers would print a stop for the wrong
-	 thread/inferior.  */
-      if (saved_context.changed ())
-	return 1;
     }
+  catch (const gdb_exception &ex)
+    {
+      exception_fprintf (gdb_stderr, ex,
+			 "Error while running hook_stop:\n");
+    }
+
+  /* If the stop hook resumes the target, then there's no point in
+     trying to notify about the previous stop; its context is
+     gone.  Likewise if the command switches thread or inferior --
+     the observers would print a stop for the wrong
+     thread/inferior.  */
+  if (saved_context.changed ())
+    return 1;
 
   /* Notify observers about the stop.  This is where the interpreters
      print the stop event.  */
@@ -9489,9 +9486,8 @@ may be interspersed with actions, with the actions being performed for\n\
 all signals cumulatively specified."));
   set_cmd_completer (c, handle_completer);
 
-  if (!dbx_commands)
+  stop_command = add_cmd ("stop", class_obscure,
-    stop_command = add_cmd ("stop", class_obscure,
+			  not_just_help_class_command, _("\
-			    not_just_help_class_command, _("\
 There is no `stop' command, but you can set a hook on `stop'.\n\
 This allows you to set a list of commands to be run each time execution\n\
 of the program stops."), &cmdlist);

gdb/main.c

@@ -61,9 +61,6 @@
    do_setshow_command will free it.  */
 char *interpreter_p;
 
-/* Whether dbx commands will be handled.  */
-int dbx_commands = 0;
-
 /* System root path, used to find libraries etc.  */
 std::string gdb_sysroot;
 
@@ -766,7 +763,6 @@ captured_main_1 (struct captured_main_args *context)
     static struct option long_options[] =
     {
       {"tui", no_argument, 0, OPT_TUI},
-      {"dbx", no_argument, &dbx_commands, 1},
       {"readnow", no_argument, NULL, OPT_READNOW},
       {"readnever", no_argument, NULL, OPT_READNEVER},
       {"r", no_argument, NULL, OPT_READNOW},
@@ -1028,9 +1024,6 @@ captured_main_1 (struct captured_main_args *context)
       }
   }
 
-  if (dbx_commands)
-    warning (_("--dbx mode is deprecated and will be removed"));
-
   save_original_signals_state (quiet);
 
   /* Try to set up an alternate signal stack for SIGSEGV handlers.  */
@@ -1437,7 +1430,6 @@ Output and user interface control:\n\n\
 "), stream);
 #endif
   gdb_puts (_("\
-  --dbx              DBX compatibility mode.\n\
   -q, --quiet, --silent\n\
 		     Do not print version number on startup.\n\n\
 "), stream);

gdb/printcmd.c

@@ -3298,18 +3298,6 @@ Use \"set variable\" for variables with names identical to set subcommands.\n\
 With a subcommand, this command modifies parts of the gdb environment.\n\
 You can see these environment settings with the \"show\" command."),
 		  &setlist, 1, &cmdlist);
-  if (dbx_commands)
-    add_com ("assign", class_vars, set_command, _("\
-Evaluate expression EXP and assign result to variable VAR.\n\
-Usage: assign VAR = EXP\n\
-This uses assignment syntax appropriate for the current language\n\
-(VAR = EXP or VAR := EXP for example).\n\
-VAR may be a debugger \"convenience\" variable (names starting\n\
-with $), a register (a few standard names starting with $), or an actual\n\
-variable in the program being debugged.  EXP is any valid expression.\n\
-Use \"set variable\" for variables with names identical to set subcommands.\n\
-\nWith a subcommand, this command modifies parts of the gdb environment.\n\
-You can see these environment settings with the \"show\" command."));
 
   /* "call" is the same as "set", but handy for dbx users to call fns.  */
   c = add_com ("call", class_vars, call_command, _("\

gdb/source.c

@@ -1926,9 +1926,6 @@ directory in which the source file was compiled into object code.\n\
 With no argument, reset the search path to $cdir:$cwd, the default."),
 	       &cmdlist);
 
-  if (dbx_commands)
-    add_com_alias ("use", directory_cmd, class_files, 0);
-
   set_cmd_completer (directory_cmd, filename_completer);
 
   add_setshow_optional_filename_cmd ("directories",

gdb/stack.c

@@ -2903,24 +2903,6 @@ find_frame_for_function (const char *function_name)
   return frame;
 }
 
-/* Implements the dbx 'func' command.  */
-
-static void
-func_command (const char *arg, int from_tty)
-{
-  if (arg == NULL)
-    return;
-
-  struct frame_info *frame = find_frame_for_function (arg);
-  if (frame == NULL)
-    error (_("'%s' not within current stack frame."), arg);
-  if (frame != get_selected_frame (NULL))
-    {
-      select_frame (frame);
-      print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC, 1);
-    }
-}
-
 /* The qcs command line flags for the "frame apply" commands.  Keep
    this in sync with the "thread apply" commands.  */
 
@@ -3560,11 +3542,6 @@ Prints the argument variables of the current stack frame.\n"),
 					false));
   set_cmd_completer_handle_brkchars (cmd, info_print_command_completer);
 
-  if (dbx_commands)
-    add_com ("func", class_stack, func_command, _("\
-Select the stack frame that contains NAME.\n\
-Usage: func NAME"));
-
   /* Install "set print raw frame-arguments", a deprecated spelling of
      "set print raw-frame-arguments".  */
   set_show_commands set_show_frame_args

gdb/symtab.c

@@ -6932,17 +6932,6 @@ Prints the global and static variables.\n"),
 				      _("global and static variables"),
 				      true));
   set_cmd_completer_handle_brkchars (c, info_vars_funcs_command_completer);
-  if (dbx_commands)
-    {
-      c = add_com ("whereis", class_info, info_variables_command,
-		   info_print_args_help (_("\
-All global and static variable names, or those matching REGEXPs.\n\
-Usage: whereis [-q] [-n] [-t TYPEREGEXP] [NAMEREGEXP]\n\
-Prints the global and static variables.\n"),
-					 _("global and static variables"),
-					 true));
-      set_cmd_completer_handle_brkchars (c, info_vars_funcs_command_completer);
-    }
 
   c = add_info ("functions", info_functions_command,
 		info_print_args_help (_("\

gdb/testsuite/gdb.base/dbx.exp

@@ -1,308 +0,0 @@
-# Copyright 1998-2022 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/>.  */
-
-
-standard_testfile average.c sum.c
-
-if {[build_executable $testfile.exp $testfile \
-	 [list $srcfile $srcfile2] debug] == -1} {
-    untested "failed to compile"
-    return -1
-}
-
-#
-# start gdb -- start gdb running, default procedure
-#
-proc dbx_gdb_start { } {
-    global prompt
-    global timeout
-    global gdb_spawn_id
-
-    save_vars { GDBFLAGS } {
-	append GDBFLAGS " -dbx"
-
-	set res [gdb_spawn]
-	if { $res != 0} {
-	    return $res
-	}
-    }
-
-    set oldtimeout $timeout
-    set timeout [expr "$timeout + 60"]
-    gdb_expect {
-        -re ".*\r\n$gdb_prompt $" {
-            verbose "GDB initialized."
-        }
-        -re "$prompt $" {
-            perror "GDB never initialized."
-	    unset gdb_spawn_id
-            return -1
-        }
-        timeout         {
-            perror "(timeout) GDB never initialized."
-	    unset gdb_spawn_id
-            return -1
-        }
-    }
-    set timeout $oldtimeout
-    # force the height to "unlimited", so no pagers get used
-    send_gdb "set height 0\n"
-    gdb_expect {
-        -re ".*$prompt $" {
-            verbose "Setting height to 0." 2
-        }
-        timeout {
-            warning "Couldn't set the height to 0."
-        }
-    }
-    # force the width to "unlimited", so no wraparound occurs
-    send_gdb "set width 0\n"
-    gdb_expect {
-        -re ".*$prompt $" {
-            verbose "Setting width to 0." 2
-        }
-        timeout {
-            warning "Couldn't set the width to 0."
-        }
-    }
-}
-
-
-proc dbx_reinitialize_dir { subdir } {
-    global gdb_prompt
-
-   send_gdb "use\n"
-    gdb_expect {
-        -re "Reinitialize source path to empty.*y or n. " {
-            send_gdb "y\n"
-            gdb_expect {
-                -re "Source directories searched.*$gdb_prompt $" {
-                    send_gdb "use $subdir\n"
-                    gdb_expect {
-                        -re "Source directories searched.*$gdb_prompt $" {
-                            verbose "Dir set to $subdir"
-                        }
-                        -re ".*$gdb_prompt $" {
-                            perror "Dir \"$subdir\" failed."
-                        }
-                    }
-                }
-                -re ".*$gdb_prompt $" {
-                    perror "Dir \"$subdir\" failed."
-                }
-            }
-        }
-        -re ".*$gdb_prompt $" {
-            perror "Dir \"$subdir\" failed."
-        }
-    }
-}
-
-# In "testsuite/config/unix-gdb.exp", the routine "gdb_load"
-# is defined as "gdb_file_cmd".  The binding of "gdb_file_cmd"
-# is done at invocation time.  Before this file is processed,
-# it binds to the definition in "testsuite/lib/gdb.exp"; after
-# this file is processed, it binds to this definition.
-# TCL lets us overrides a previous routine definition without a
-# warning (isn't that special?).
-#
-# This means that tests before use "file" to load a target, and
-# tests afterwards use the pair "symbol-file" "exec-file".
-#
-# I'm leaving it as it is for now because at the moment it
-# is the only test we have of the use of the combination of
-# "symbol-file" and "exec-file" to load a debugging target (the
-# other definition uses "file". 
-#
-# Symbol-file and exec-file should be tested explicitly, not
-# as a side effect of running a particular test (in this case,
-# "testsuite/gdb.compat/dbx.exp").
-#
-# CM: Renamed the procedure so it does not override the orginal file name.
-#     Having the test suite change behavior depending on the tests run makes
-#     it extremely difficult to reproduce errors. I've also added a
-#     "dbx_gdb_load" procedure.  This and only this test will call these
-#     procedures now. I also added an "expect" to the "send exec-file" line.
-#     The "expect" waits for a prompt to appear. Otherwise, if the tests run
-#     too quickly, the caller could send another command before the prompt
-#     of this command returns, causing the test to get out of sync and fail
-#     seemingly randomly or only on a loaded system.
-#
-# Problem is, though, that the testsuite config files can override the definition of
-# gdb_load (without notice, as was mentioned above). Unfortunately, the gdb_load proc
-# that was copied into this test was a copy of the unix native version.
-#
-# The real problem that we're attempting to solve is how to load an exec and symbol
-# file into gdb for a dbx session. So why not just override gdb_file_cmd with the
-# right sequence of events, allowing gdb_load to do its normal thing? This way
-# remotes and simulators will work, too.
-#
-
-proc local_gdb_file_cmd {arg} {
-    global loadpath
-    global loadfile
-    global GDB
-    global gdb_prompt
-    global spawn_id
-    upvar timeout timeout
-    global last_loaded_file
-
-    set last_loaded_file $arg
-
-    if [is_remote host] {
-        set arg [remote_download host $arg]
-        if { $arg == "" } {
-            error "download failed"
-            return -1
-        }
-    }
-
-    send_gdb "symbol-file $arg\n"
-    gdb_expect {
-        -re "Reading symbols from.*$gdb_prompt $" {
-            verbose "\t\tLoaded $arg into the $GDB"
-            send_gdb "exec-file $arg\n" 
-            gdb_expect {
-	        -re "A program is being debugged already.*Kill it.*y or n. $" {
-	            send_gdb "y\n"
-	                verbose "\t\tKilling previous program being debugged"
-	            exp_continue
-	        }
-                -re ".*$gdb_prompt $" {
-                    verbose "\t\tLoaded $arg with new symbol table into $GDB"
-                    return 0
-                }
-                timeout {
-                    perror "(timeout) Couldn't load $arg"
-                    return -1
-                }
-            }
-            return 0
-        }
-        -re "has no symbol-table.*$gdb_prompt $" {
-            perror "$arg wasn't compiled with \"-g\""
-            return -1
-        }
-        -re "Load new symbol table from \".*\".*y or n. $" {
-            send_gdb "y\n"
-	    exp_continue
-        }
-        -re ".*No such file or directory.*$gdb_prompt $" {
-            perror "($arg) No such file or directory\n"
-            return -1
-        }
-        -re "$gdb_prompt $" {
-            perror "couldn't load $arg into $GDB."
-            return -1
-            }
-        timeout {
-            perror "couldn't load $arg into $GDB (timed out)."
-            return -1
-        }
-        eof {
-            # This is an attempt to detect a core dump, but seems not to
-            # work.  Perhaps we need to match .* followed by eof, in which
-            # expect does not seem to have a way to do that.
-            perror "couldn't load $arg into $GDB (end of file)."
-            return -1
-        }
-    }
-}
-
-#
-#test_breakpoints
-#
-proc test_breakpoints { } {
-    set stop_line [gdb_get_line_number "stop-in-main"]
-    gdb_test "stop in main" "Breakpoint.*at.*: file.*average\.c, line $stop_line\."
-    gdb_test "status" "Num.*Type.*Disp.*Enb.*Address.*What\r\n1\[ \r\]+breakpoint\[ \r\]+keep y.*in main at.*average\.c:$stop_line.*"
-    set stop_line [gdb_get_line_number "stop-at-call"]
-    gdb_test "stop at average.c:$stop_line" "Breakpoint.*at.*: file.*average\.c, line $stop_line.*"
-    gdb_test "stop in average.c:$stop_line" "Usage: stop in <function . address>"
-    gdb_test "stop at main" "Usage: stop at LINE"
-}
-
-#
-#test_assign
-#
-proc test_assign { } {
-    global decimal
-    global gdb_prompt
-
-    gdb_run_cmd
-    set test "running to main"
-    gdb_test_multiple "" $test {
-        -re "Break.* at .*:$decimal.*$gdb_prompt $" {
-	    pass $test
-	}
-        -re "Breakpoint \[0-9\]*, \[0-9xa-f\]* in .*$gdb_prompt $" {
-	    pass $test
-	}
-    }
-    send_gdb "assign first=1\n"
-    gdb_expect {
-      -re "No symbol \"first\" in current context.*$" { fail "assign first" }
-      -re "$gdb_prompt $" { pass "assign first" }
-      timeout { fail "assign first (timeout)" }
-    }
-    gdb_test "print first" ".1 = 1"
-}
-
-#
-#test_whereis
-#
-proc test_whereis { } {
-    gdb_test "whereis my_list" "All variables matching regular expression \"my_list\":\r\n\r\nFile.*average\.c:\r\n.*\tstatic int my_list\\\[10\\\];"
-}
-
-#
-#test_func
-#
-proc test_func { } {
-    global decimal
-    global srcfile2
-    gdb_test "cont" ".*" "cont 1"
-    gdb_test "step" ".*"
-    gdb_test "func sum" "'sum' not within current stack frame\."
-    set stop_line [gdb_get_line_number "stop-in-sum" $srcfile2]
-    gdb_test "stop in sum" "Breakpoint.*at.*: file.*sum\.c, line $stop_line\."
-    gdb_test "cont" ".*" "cont 2"
-    gdb_test "func print_average" ".*in print_average.*\\(list=.*, low=0, high=6\\).*at.*average\.c:${decimal}\r\n${decimal}\[ \t\]+total = sum\\(list, low, high\\);"
-}
-
-# Start with a fresh gdb.
-
-gdb_exit
-
-with_override gdb_file_cmd local_gdb_file_cmd {
-    save_vars GDBFLAGS {
-	set GDBFLAGS "$GDBFLAGS --dbx"
-
-	gdb_start
-	dbx_reinitialize_dir $srcdir/$subdir
-	gdb_load ${binfile}
-
-	test_breakpoints
-	test_assign
-	test_whereis
-	gdb_test "file average.c:1" "1\[ \t\]+/. This is a sample program.*"
-	test_func
-
-	#exit and cleanup
-	gdb_exit
-    }
-}
-
-return 0