The purpose of this concept is to turn the load of debugging
information off, either globally (via the '--readnever' option), or
objfile-specific. The implementation proposed here is an extension of
the patch distributed with Fedora GDB; looking at the Fedora patch
itself and the history, one can see some reasons why it was never
resubmitted:
- The patch appears to have been introduced as a workaround, at
least initially;
- The patch is far from perfect, as it simply shunts the load of
DWARF debugging information, without really worrying about the
other debug format.
- Who really does non-symbolic debugging anyways?
One use of this feature 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.
This patch expands the version shipped with Fedora GDB in order to
make the feature available for all the debuginfo backends, not only
for DWARF. It also implements a per-objfile flag which can be
activated by using the "-readnever" command when using the
'add-symbol-file' or 'symbol-file' commands.
It's also worth mentioning that this patch tests whether GDB correctly
fails to initialize if both '--readnow' and '--readnever' options are
passed.
Tested on the BuildBot.
gdb/ChangeLog:
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.
gdb/doc/ChangeLog:
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'.
gdb/testsuite/ChangeLog:
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.
The purpose of this concept is to turn the load of debugging
information off, either globally (via the '--readnever' option), or
objfile-specific. The implementation proposed here is an extension of
the patch distributed with Fedora GDB; looking at the Fedora patch
itself and the history, one can see some reasons why it was never
resubmitted:
- The patch appears to have been introduced as a workaround, at
least initially;
- The patch is far from perfect, as it simply shunts the load of
DWARF debugging information, without really worrying about the
other debug format.
- Who really does non-symbolic debugging anyways?
One use of this feature 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.
This patch expands the version shipped with Fedora GDB in order to
make the feature available for all the debuginfo backends, not only
for DWARF. It also implements a per-objfile flag which can be
activated by using the "-readnever" command when using the
'add-symbol-file' or 'symbol-file' commands.
It's also worth mentioning that this patch tests whether GDB correctly
fails to initialize if both '--readnow' and '--readnever' options are
passed.
Tested on the BuildBot.
gdb/ChangeLog:
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.
gdb/doc/ChangeLog:
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'.
gdb/testsuite/ChangeLog:
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.
This applies the second part of GDB's End of Year Procedure, which
updates the copyright year range in all of GDB's files.
gdb/ChangeLog:
Update copyright year range in all GDB files.
This makes these flag types be "enum flag" types. The benefit is
making use of C++'s stronger typing -- mixing the flags types by
mistake errors at compile time.
This caught one old bug in symbol_file_add_main_1 already, fixed by
this patch as well:
@@ -1318,7 +1326,7 @@ symbol_file_add_main_1 (const char *args, int from_tty, int flags)
what is frameless. */
reinit_frame_cache ();
- if ((flags & SYMFILE_NO_READ) == 0)
+ if ((add_flags & SYMFILE_NO_READ) == 0)
set_initial_language ();
}
Above, "flags" are objfile flags, not symfile_add_flags. So that was
actually checking for "flag & OBJF_PSYMTABS_READ", which has the same
value as SYMFILE_NO_READ...
I moved the flags definitions to separate files to break circular
dependencies.
Built with --enable-targets=all and tested on x86-64 Fedora 23.
gdb/ChangeLog:
2016-10-26 Pedro Alves <palves@redhat.com>
* coffread.c (coff_symfile_read): Use symfile_add_flags.
* dbxread.c (dbx_symfile_read): Ditto.
* elfread.c (elf_symfile_read): Ditto.
* inferior.h: Include symfile-add-flags.h.
(struct inferior) <symfile_flags>: Now symfile_add_flags.
* machoread.c (macho_add_oso_symfile, macho_symfile_read_all_oso)
(macho_symfile_read, mipscoff_symfile_read): Use
symfile_add_flags.
* objfile-flags.h: New file.
* objfiles.c (allocate_objfile): Use objfile_flags.
* objfiles.h: Include objfile-flags.h.
(struct objfile) <flags>: Now an objfile_flags.
(OBJF_REORDERED, OBJF_SHARED, OBJF_READNOW, OBJF_USERLOADED)
(OBJF_PSYMTABS_READ, OBJF_MAINLINE, OBJF_NOT_FILENAME): Delete.
Converted to an enum-flags in objfile-flags.h.
(allocate_objfile): Use objfile_flags.
* python/py-objfile.c (objfpy_add_separate_debug_file): Remove
unnecessary local.
* solib.c (solib_read_symbols, solib_add)
(reload_shared_libraries_1): Use symfile_add_flags.
* solib.h: Include "symfile-add-flags.h".
(solib_read_symbols): Use symfile_add_flags.
* symfile-add-flags.h: New file.
* symfile-debug.c (debug_sym_read): Use symfile_add_flags.
* symfile-mem.c (symbol_file_add_from_memory): Use
symfile_add_flags.
* symfile.c (read_symbols, syms_from_objfile_1)
(syms_from_objfile, finish_new_objfile): Use symfile_add_flags.
(symbol_file_add_with_addrs): Use symfile_add_flags and
objfile_flags.
(symbol_file_add_separate): Use symfile_add_flags.
(symbol_file_add_from_bfd, symbol_file_add): Use symfile_add_flags
and objfile_flags.
(symbol_file_add_main_1): : Use objfile_flags. Fix add_flags vs
flags confusion.
(symbol_file_command): Use objfile_flags.
(add_symbol_file_command): Use symfile_add_flags and
objfile_flags.
(clear_symtab_users): Use symfile_add_flags.
* symfile.h: Include "symfile-add-flags.h" and "objfile-flags.h".
(struct sym_fns) <sym_read>: Use symfile_add_flags.
(clear_symtab_users): Use symfile_add_flags.
(enum symfile_add_flags): Delete, moved to symfile-add-flags.h and
converted to enum-flags.
(symbol_file_add, symbol_file_add_from_bfd)
(symbol_file_add_separate): Use symfile_add_flags.
* xcoffread.c (xcoff_initial_scan): Use symfile_add_flags.
Joel Brobecker
Sergio Durigan Junior
Pedro Alves