Revert "Add support for the readnever concept"

This reverts commit e2e321740ce2e36a97be2a410cd56eebaa2304aa.

It was mistakenly pushed.

15 files changed, 39 insertions, 303 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 9f4b5e5..4eef5a9 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -14,37 +14,6 @@
 	* ada-exp.y (block_lookup): Make sure "syms" gets xfree'ed.
 	(write_var_or_type, write_name_assoc): Likewise.
 
-2017-12-01  Andrew Cagney  <cagney@redhat.com>
-	    Joel Brobecker  <brobecker@adacore.com>
-	    Sergio Durigan Junior  <sergiodj@redhat.com>
-
-	* NEWS (Changes since GDB 8.0: Mention new '--readnever'
-	feature.
-	* coffread.c (coff_symfile_read): Do not map over sections with
-	'coff_locate_sections' if readnever is on.
-	* dwarf2read.c (dwarf2_has_info): Return 0 if
-	readnever is on.
-	* elfread.c (elf_symfile_read): Do not map over sections with
-	'elf_locate_sections' if readnever is on.
-	* main.c (validate_readnow_readnever): New function.
-	(captured_main_1): Add support for --readnever.
-	(print_gdb_help): Document --readnever.
-	* objfile-flags.h (enum objfile_flag) <OBJF_READNEVER>: New
-	flag.
-	* symfile.c (readnever_symbol_files): New global.
-	(symbol_file_add_with_addrs): Set 'OBJF_READNEVER' when
-	'READNEVER_SYMBOL_FILES' is set.
-	(validate_readnow_readnever): New function.
-	(symbol_file_command): Handle '-readnever' option.
-	Call 'validate_readnow_readnever'.
-	(add_symbol_file_command): Handle '-readnever' option.
-	Call 'validate_readnow_readnever'.
-	(_initialize_symfile): Document new '-readnever' option for
-	both 'symbol-file' and 'add-symbol-file' commands.
-	* top.h (readnever_symbol_files): New extern global.
-	* xcoffread.c (xcoff_initial_scan): Do not read debug
-	information if readnever is on.
-
 2017-12-01  Tom Tromey  <tom@tromey.com>
 
 	* Makefile.in (all_deps_files): New variable.
diff --git a/gdb/NEWS b/gdb/NEWS
index ff9a819..06df528 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -3,12 +3,6 @@
 
 *** Changes since GDB 8.0
 
-* New "--readnever" command line option instructs GDB to not read each
-  symbol file's symbolic debug information.  This makes startup faster
-  but at the expense of not being able to perform symbolic debugging.
-  This option is intended for use cases where symbolic debugging will
-  not be used, e.g., when you only need to dump the debuggee's core.
-
 * GDB now uses the GNU MPFR library, if available, to emulate target
   floating-point arithmetic during expression evaluation when the target
   uses different floating-point formats than the host.  At least version
diff --git a/gdb/coffread.c b/gdb/coffread.c
index 98f6eec..62b6d79 100644
--- a/gdb/coffread.c
+++ b/gdb/coffread.c
@@ -699,8 +699,7 @@ coff_symfile_read (struct objfile *objfile, symfile_add_flags symfile_flags)
 	}
     }
 
-  if (!(objfile->flags & OBJF_READNEVER))
-    bfd_map_over_sections (abfd, coff_locate_sections, (void *) info);
+  bfd_map_over_sections (abfd, coff_locate_sections, (void *) info);
 
   if (info->stabsects)
     {
diff --git a/gdb/doc/ChangeLog b/gdb/doc/ChangeLog
index fa8180f..6d23a77 100644
--- a/gdb/doc/ChangeLog
+++ b/gdb/doc/ChangeLog
@@ -1,11 +1,3 @@
-2017-12-01  Andrew Cagney  <cagney@redhat.com>
-	    Joel Brobecker  <brobecker@adacore.com>
-	    Sergio Durigan Junior  <sergiodj@redhat.com>
-
-	* gdb.texinfo (File Options): Document --readnever.
-	(Commands to Specify Files): Likewise, for 'symbol-file' and
-	'add-symbol-file'.
-
 2017-11-29  Pedro Alves  <palves@redhat.com>
 
 	PR c++/19436
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 005fed8..4f55222 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -1037,16 +1037,6 @@ Read each symbol file's entire symbol table immediately, rather than
 the default, which is to read it incrementally as it is needed.
 This makes startup slower, but makes future operations faster.
 
-@item --readnever
-@anchor{--readnever}
-@cindex @code{--readnever}, command-line option
-Do not read each symbol file's symbolic debug information.  This makes
-startup faster but at the expense of not being able to perform
-symbolic debugging.  DWARF unwind information is also not read,
-meaning backtraces may become incomplete or inaccurate.  One use of
-this is when a user simply wants to do the following sequence: attach,
-dump core, detach.  Loading the debugging information in this case is
-an unnecessary cause of delay.
 @end table
 
 @node Mode Options
@@ -18586,15 +18576,6 @@ tables by using the @samp{-readnow} option with any of the commands that
 load symbol table information, if you want to be sure @value{GDBN} has the
 entire symbol table available.
 
-@cindex @code{-readnever}, option for symbol-file command
-@cindex never read symbols
-@cindex symbols, never read
-@item symbol-file @r{[} -readnever @r{]} @var{filename}
-@itemx file @r{[} -readnever @r{]} @var{filename}
-You can instruct @value{GDBN} to never read the symbolic information
-contained in @var{filename} by using the @samp{-readnever} option.
-@xref{--readnever}.
-
 @c FIXME: for now no mention of directories, since this seems to be in
 @c flux.  13mar1992 status is that in theory GDB would look either in
 @c current dir or in same dir as myprog; but issues like competing
@@ -18623,7 +18604,7 @@ the program is running.  To do this, use the @code{kill} command
 @kindex add-symbol-file
 @cindex dynamic linking
 @item add-symbol-file @var{filename} @var{address}
-@itemx add-symbol-file @var{filename} @var{address} @r{[} -readnow @r{|} -readnever @r{]}
+@itemx add-symbol-file @var{filename} @var{address} @r{[} -readnow @r{]}
 @itemx add-symbol-file @var{filename} @var{address} -s @var{section} @var{address} @dots{}
 The @code{add-symbol-file} command reads additional symbol table
 information from the file @var{filename}.  You would use this command
diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 78c663c..2572179 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -2319,9 +2319,6 @@ int
 dwarf2_has_info (struct objfile *objfile,
                  const struct dwarf2_debug_sections *names)
 {
-  if (objfile->flags & OBJF_READNEVER)
-    return 0;
-
   dwarf2_per_objfile = ((struct dwarf2_per_objfile *)
 			objfile_data (objfile, dwarf2_objfile_data_key));
   if (!dwarf2_per_objfile)
diff --git a/gdb/elfread.c b/gdb/elfread.c
index b806ca3..f248302 100644
--- a/gdb/elfread.c
+++ b/gdb/elfread.c
@@ -1171,8 +1171,7 @@ elf_symfile_read (struct objfile *objfile, symfile_add_flags symfile_flags)
   struct elfinfo ei;
 
   memset ((char *) &ei, 0, sizeof (ei));
-  if (!(objfile->flags & OBJF_READNEVER))
-    bfd_map_over_sections (abfd, elf_locate_sections, (void *) & ei);
+  bfd_map_over_sections (abfd, elf_locate_sections, (void *) & ei);
 
   elf_read_minimal_symbols (objfile, symfile_flags, &ei);
 
diff --git a/gdb/main.c b/gdb/main.c
index 8f04da1..61168fa 100644
--- a/gdb/main.c
+++ b/gdb/main.c
@@ -402,19 +402,6 @@ symbol_file_add_main_adapter (const char *arg, int from_tty)
   symbol_file_add_main (arg, add_flags);
 }
 
-/* Perform validation of the '--readnow' and '--readnever' flags.  */
-
-static void
-validate_readnow_readnever ()
-{
-  if (readnever_symbol_files && readnow_symbol_files)
-    {
-      error (_("%s: '--readnow' and '--readnever' cannot be "
-	       "specified simultaneously"),
-	     gdb_program_name);
-    }
-}
-
 /* Type of this option.  */
 enum cmdarg_kind
 {
@@ -592,17 +579,14 @@ captured_main_1 (struct captured_main_args *context)
       OPT_NOWINDOWS,
       OPT_WINDOWS,
       OPT_IX,
-      OPT_IEX,
-      OPT_READNOW,
-      OPT_READNEVER
+      OPT_IEX
     };
     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},
+      {"readnow", no_argument, &readnow_symbol_files, 1},
+      {"r", no_argument, &readnow_symbol_files, 1},
       {"quiet", no_argument, &quiet, 1},
       {"q", no_argument, &quiet, 1},
       {"silent", no_argument, &quiet, 1},
@@ -825,20 +809,6 @@ captured_main_1 (struct captured_main_args *context)
 	    }
 	    break;
 
-	  case OPT_READNOW:
-	    {
-	      readnow_symbol_files = 1;
-	      validate_readnow_readnever ();
-	    }
-	    break;
-
-	  case OPT_READNEVER:
-	    {
-	      readnever_symbol_files = 1;
-	      validate_readnow_readnever ();
-	    }
-	    break;
-
 	  case '?':
 	    error (_("Use `%s --help' for a complete list of options."),
 		   gdb_program_name);
@@ -1213,7 +1183,6 @@ Selection of debuggee and its files:\n\n\
   --se=FILE          Use FILE as symbol file and executable file.\n\
   --symbols=SYMFILE  Read symbols from SYMFILE.\n\
   --readnow          Fully read symbol files on first access.\n\
-  --readnever        Do not read symbol files.\n\
   --write            Set writing into executable and core files.\n\n\
 "), stream);
   fputs_unfiltered (_("\
diff --git a/gdb/objfile-flags.h b/gdb/objfile-flags.h
index f2a2ccf..43ba8aa 100644
--- a/gdb/objfile-flags.h
+++ b/gdb/objfile-flags.h
@@ -64,10 +64,6 @@ enum objfile_flag
        unrelated to filesystem names.  It can be for example
        "<image in memory>".  */
     OBJF_NOT_FILENAME = 1 << 6,
-
-    /* User requested that we do not read this objfile's symbolic
-       information.  */
-    OBJF_READNEVER = 1 << 7,
   };
 
 DEF_ENUM_FLAGS_TYPE (enum objfile_flag, objfile_flags);
diff --git a/gdb/symfile.c b/gdb/symfile.c
index 36b34e6..4bbe0b5 100644
--- a/gdb/symfile.c
+++ b/gdb/symfile.c
@@ -81,7 +81,6 @@ static void clear_symtab_users_cleanup (void *ignore);
 
 /* Global variables owned by this file.  */
 int readnow_symbol_files;	/* Read full symbols immediately.  */
-int readnever_symbol_files;	/* Never read full symbols.  */
 
 /* Functions this file defines.  */
 
@@ -1132,12 +1131,6 @@ symbol_file_add_with_addrs (bfd *abfd, const char *name,
       flags |= OBJF_READNOW;
       add_flags &= ~SYMFILE_NO_READ;
     }
-  else if (readnever_symbol_files
-	   || (parent != NULL && (parent->flags & OBJF_READNEVER)))
-    {
-      flags |= OBJF_READNEVER;
-      add_flags |= SYMFILE_NO_READ;
-    }
 
   /* Give user a chance to burp if we'd be
      interactively wiping out any existing symbols.  */
@@ -1601,16 +1594,6 @@ find_separate_debug_file_by_debuglink (struct objfile *objfile)
   return debugfile;
 }
 
-/* Make sure that OBJF_{READNOW,READNEVER} are not set
-   simultaneously.  */
-
-static void
-validate_readnow_readnever (objfile_flags flags)
-{
-  if ((flags & OBJF_READNOW) && (flags & OBJF_READNEVER))
-    error (_("-readnow and -readnever cannot be used simultaneously"));
-}
-
 /* This is the symbol-file command.  Read the file, analyze its
    symbols, and add a struct symtab to a symtab list.  The syntax of
    the command is rather bizarre:
@@ -1648,20 +1631,17 @@ symbol_file_command (const char *args, int from_tty)
 	{
 	  if (strcmp (arg, "-readnow") == 0)
 	    flags |= OBJF_READNOW;
-	  else if (strcmp (arg, "-readnever") == 0)
-	    flags |= OBJF_READNEVER;
 	  else if (*arg == '-')
 	    error (_("unknown option `%s'"), arg);
 	  else
-	    name = arg;
+	    {
+	      symbol_file_add_main_1 (arg, add_flags, flags);
+	      name = arg;
+	    }
 	}
 
       if (name == NULL)
 	error (_("no symbol file name was specified"));
-
-      validate_readnow_readnever (flags);
-
-      symbol_file_add_main_1 (name, add_flags, flags);
     }
 }
 
@@ -2258,8 +2238,6 @@ add_symbol_file_command (const char *args, int from_tty)
 	    }
 	  else if (strcmp (arg, "-readnow") == 0)
 	    flags |= OBJF_READNOW;
-	  else if (strcmp (arg, "-readnever") == 0)
-	    flags |= OBJF_READNEVER;
 	  else if (strcmp (arg, "-s") == 0)
 	    {
 	      expecting_sec_name = 1;
@@ -2270,8 +2248,6 @@ add_symbol_file_command (const char *args, int from_tty)
 	}
     }
 
-  validate_readnow_readnever (flags);
-
   /* This command takes at least two arguments.  The first one is a
      filename, and the second is the address where this file has been
      loaded.  Abort now if this address hasn't been provided by the
@@ -3902,29 +3878,26 @@ _initialize_symfile (void)
 
   observer_attach_free_objfile (symfile_free_objfile);
 
-#define READNOW_READNEVER_HELP \
+#define READNOW_HELP \
   "The '-readnow' option will cause GDB to read the entire symbol file\n\
 immediately.  This makes the command slower, but may make future operations\n\
-faster.\n\
-The '-readnever' option will prevent GDB from reading the symbol file's\n\
-symbolic debug information."
+faster."
 
   c = add_cmd ("symbol-file", class_files, symbol_file_command, _("\
 Load symbol table from executable file FILE.\n\
-Usage: symbol-file [-readnow | -readnever] FILE\n\
+Usage: symbol-file [-readnow] FILE\n\
 The `file' command can also load symbol tables, as well as setting the file\n\
-to execute.\n" READNOW_READNEVER_HELP), &cmdlist);
+to execute.\n" READNOW_HELP), &cmdlist);
   set_cmd_completer (c, filename_completer);
 
   c = add_cmd ("add-symbol-file", class_files, add_symbol_file_command, _("\
 Load symbols from FILE, assuming FILE has been dynamically loaded.\n\
-Usage: add-symbol-file FILE ADDR [-readnow | -readnever | \
--s SECT-NAME SECT-ADDR]...\n\
+Usage: add-symbol-file FILE ADDR [-readnow | -s SECT-NAME SECT-ADDR]...\n\
 ADDR is the starting address of the file's text.\n\
 Each '-s' argument provides a section name and address, and\n\
 should be specified if the data and bss segments are not contiguous\n\
 with the text.  SECT-NAME is a section name to be loaded at SECT-ADDR.\n"
-READNOW_READNEVER_HELP),
+READNOW_HELP),
 	       &cmdlist);
   set_cmd_completer (c, filename_completer);
 
diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 9f84eea..69e1c3a 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,9 +1,3 @@
-2017-12-01  Joel Brobecker  <brobecker@adacore.com>
-	    Sergio Durigan Junior  <sergiodj@redhat.com>
-	    Pedro Alves  <palves@redhat.com>
-
-	* gdb.base/readnever.c, gdb.base/readnever.exp: New files.
-
 2017-12-01  Yao Qi  <yao.qi@linaro.org>
 
 	* gdb.arch/aarch64-atomic-inst.exp: Replace mail address with
diff --git a/gdb/testsuite/gdb.base/readnever.c b/gdb/testsuite/gdb.base/readnever.c
deleted file mode 100644
index 6489e89..0000000
--- a/gdb/testsuite/gdb.base/readnever.c
+++ /dev/null
@@ -1,41 +0,0 @@
-/* Copyright 2016-2017 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/>.  */
-
-static void
-fun_three (int a, char b, void *c)
-{
-  /* Do nothing.  */
-}
-
-static void
-fun_two (unsigned int p, const char *y)
-{
-  fun_three ((int) p, '1', (void *) y);
-}
-
-static void
-fun_one (int *x)
-{
-  fun_two (10, (const char *) x);
-}
-
-int
-main (void)
-{
-  int a = 10;
-
-  fun_one (&a);
-  return 0;
-}
diff --git a/gdb/testsuite/gdb.base/readnever.exp b/gdb/testsuite/gdb.base/readnever.exp
deleted file mode 100644
index 151f12a..0000000
--- a/gdb/testsuite/gdb.base/readnever.exp
+++ /dev/null
@@ -1,83 +0,0 @@
-# Copyright 2016-2017 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 .c
-
-if { [build_executable "failed to build" $testfile $srcfile { debug }] == -1 } {
-    untested "Couldn't compile ${srcfile}"
-    return -1
-}
-
-save_vars { GDBFLAGS } {
-    append GDBFLAGS " --readnever"
-    clean_restart ${binfile}
-}
-
-if ![runto_main] then {
-    perror "couldn't run to breakpoint"
-    continue
-}
-
-gdb_test "break fun_three" \
-         "Breakpoint $decimal at $hex"
-
-gdb_test "continue" \
-         "Breakpoint $decimal, $hex in fun_three \\(\\)"
-
-gdb_test "backtrace" \
-         [multi_line "#0  $hex in fun_three \\(\\)" \
-                     "#1  $hex in fun_two \\(\\)" \
-                     "#2  $hex in fun_one \\(\\)" \
-                     "#3  $hex in main \\(\\)" ]
-
-gdb_test_no_output "maint info symtabs" \
-    "maint info symtabs no output for --readnever"
-gdb_test_no_output "maint info psymtabs" \
-    "maint info psymtabs no output for --readnever"
-
-# Test invalid combination of flags.
-save_vars { GDBFLAGS } {
-    append GDBFLAGS " --readnever --readnow"
-    gdb_exit
-    gdb_spawn
-
-    set test "test readnow and readnever at the same time"
-    gdb_test_multiple "" $test {
-	"'--readnow' and '--readnever' cannot be specified simultaneously" {
-	    pass $test
-	    set test "expect eof after failure"
-	    gdb_test_multiple "" $test {
-		eof {
-		    pass $test
-		}
-	    }
-	}
-    }
-}
-
-
-# Test symbol-file's -readnever option.
-
-# Restart GDB without the --readnever option.
-gdb_exit
-gdb_start
-gdb_test "symbol-file ${binfile}0.o -readnever" \
-    "Reading symbols from ${binfile}0\.o\.\.\.\\\(no debugging symbols found\\\)\.\.\.done\." \
-    "use symbol-file -readnever"
-
-gdb_test_no_output "maint info symtabs" \
-    "maint info symtabs no output for symbol-file -readnever"
-gdb_test_no_output "maint info psymtabs" \
-    "maint info psymtabs no output for symbol-file -readnever"
diff --git a/gdb/top.h b/gdb/top.h
index a1df64f..26fe878 100644
--- a/gdb/top.h
+++ b/gdb/top.h
@@ -267,7 +267,6 @@ extern int gdb_in_secondary_prompt_p (struct ui *ui);
 
 /* From random places.  */
 extern int readnow_symbol_files;
-extern int readnever_symbol_files;
 
 /* Perform _initialize initialization.  */
 extern void gdb_init (char *);
diff --git a/gdb/xcoffread.c b/gdb/xcoffread.c
index b1c634c..46a43bc9 100644
--- a/gdb/xcoffread.c
+++ b/gdb/xcoffread.c
@@ -2975,33 +2975,31 @@ xcoff_initial_scan (struct objfile *objfile, symfile_add_flags symfile_flags)
       /* Read the string table.  */
       init_stringtab (abfd, stringtab_offset, objfile);
 
-      /* Read the .debug section, if present and if we're not ignoring
-	 it.  */
-      if (!(objfile->flags & OBJF_READNEVER))
-	{
-	  struct bfd_section *secp;
-	  bfd_size_type length;
-	  bfd_byte *debugsec = NULL;
+      /* Read the .debug section, if present.  */
+      {
+	struct bfd_section *secp;
+	bfd_size_type length;
+	bfd_byte *debugsec = NULL;
 
-	  secp = bfd_get_section_by_name (abfd, ".debug");
-	  if (secp)
-	    {
-	      length = bfd_section_size (abfd, secp);
-	      if (length)
-		{
-		  debugsec
-		    = (bfd_byte *) obstack_alloc (&objfile->objfile_obstack,
-						  length);
+	secp = bfd_get_section_by_name (abfd, ".debug");
+	if (secp)
+	  {
+	    length = bfd_section_size (abfd, secp);
+	    if (length)
+	      {
+		debugsec
+		  = (bfd_byte *) obstack_alloc (&objfile->objfile_obstack,
+						length);
 
-		  if (!bfd_get_full_section_contents (abfd, secp, &debugsec))
-		    {
-		      error (_("Error reading .debug section of `%s': %s"),
-			     name, bfd_errmsg (bfd_get_error ()));
-		    }
-		}
-	    }
-	  info->debugsec = (char *) debugsec;
-	}
+		if (!bfd_get_full_section_contents (abfd, secp, &debugsec))
+		  {
+		    error (_("Error reading .debug section of `%s': %s"),
+			   name, bfd_errmsg (bfd_get_error ()));
+		  }
+	      }
+	  }
+	info->debugsec = (char *) debugsec;
+      }
     }
 
   /* Read the symbols.  We keep them in core because we will want to