Since Fedora started to use DWZ DWARF compressor:
http://fedoraproject.org/wiki/Features/DwarfCompressor
GDB has slowed down a lot. To make it clear - DWZ is DWARF structure
rearrangement, "compressor" does not mean any zlib style data compression.
This patch reduces LibreOffice backtrace from 5 minutes to 3 seconds (100x)
and it also reduces memory consumption 20x.
[ benchmark is at the bottom of this mail ]
Example of DWZ output:
------------------------------------------------------------------------------
Compilation Unit @ offset 0xc4:
<0><cf>: Abbrev Number: 17 (DW_TAG_partial_unit)
<d0> DW_AT_stmt_list : 0x0
<d4> DW_AT_comp_dir : (indirect string, offset: 0x6f): /usr/src/debug/gdb-7.7.1/build-x86_64-redhat-linux-gnu/gdb
<1><d8>: Abbrev Number: 9 (DW_TAG_typedef)
<d9> DW_AT_name : (indirect string, offset: 0x827dc): size_t
<dd> DW_AT_decl_file : 4
<de> DW_AT_decl_line : 212
<df> DW_AT_type : <0xae>
Compilation Unit @ offset 0xe4:
<0><ef>: Abbrev Number: 13 (DW_TAG_partial_unit)
<f0> DW_AT_stmt_list : 0x0
<f4> DW_AT_comp_dir : (indirect string, offset: 0x6f): /usr/src/debug/gdb-7.7.1/build-x86_64-redhat-linux-gnu/gdb
<1><f8>: Abbrev Number: 45 (DW_TAG_typedef)
<f9> DW_AT_name : (indirect string, offset: 0x251): __off_t
<fd> DW_AT_decl_file : 3
<fe> DW_AT_decl_line : 131
<ff> DW_AT_type : <0x68>
Compilation Unit @ offset 0x62d9f9:
<0><62da04>: Abbrev Number: 20 (DW_TAG_compile_unit)
[...]
<62da12> DW_AT_low_pc : 0x807e10
<62da1a> DW_AT_high_pc : 134
<62da1c> DW_AT_stmt_list : 0xf557e
<1><62da20>: Abbrev Number: 7 (DW_TAG_imported_unit)
<62da21> DW_AT_import : <0xcf> [Abbrev Number: 17]
------------------------------------------------------------------------------
One can see all DW_TAG_partial_unit have DW_AT_stmt_list 0x0 which causes
repeated decoding of that .debug_line unit on each DW_TAG_imported_unit.
This was OK before as each DW_TAG_compile_unit has its own .debug_line unit.
But since the introduction of DW_TAG_partial_unit by DWZ one should cache
read-in DW_AT_stmt_list .debug_line units.
Fortunately one does not need to cache whole
struct linetable *symtab->linetable
and other data from .debug_line mapping PC<->lines
------------------------------------------------------------------------------
Line Number Statements:
Extended opcode 2: set Address to 0x45c880
Advance Line by 25 to 26
Copy
------------------------------------------------------------------------------
as the only part of .debug_line which GDB needs for DW_TAG_partial_unit is:
------------------------------------------------------------------------------
The Directory Table:
../../gdb
/usr/include/bits
[...]
The File Name Table:
Entry Dir Time Size Name
1 1 0 0 gdb.c
2 2 0 0 string3.h
[...]
------------------------------------------------------------------------------
specifically referenced in GDB for DW_AT_decl_file at a single place:
------------------------------------------------------------------------------
fe = &cu->line_header->file_names[file_index - 1];
SYMBOL_SYMTAB (sym) = fe->symtab;
------------------------------------------------------------------------------
This is because for some reason DW_TAG_partial_unit never contains PC-related
DWARF information. I do not know exactly why, the compression ratio is a bit
lower due to it but thanksfully currently it is that way:
dwz.c:
------------------------------------------------------------------------------
/* These attributes reference code, prevent moving
DIEs with them. */
case DW_AT_low_pc:
case DW_AT_high_pc:
case DW_AT_entry_pc:
case DW_AT_ranges:
die->die_ck_state = CK_BAD;
+
/* State of checksum computation. Not computed yet, computed and
suitable for moving into partial units, currently being computed
and finally determined unsuitable for moving into partial units. */
enum { CK_UNKNOWN, CK_KNOWN, CK_BEING_COMPUTED, CK_BAD } die_ck_state : 2;
------------------------------------------------------------------------------
I have also verified also real-world Fedora debuginfo files really comply with
that assumption with dwgrep
https://github.com/pmachata/dwgrep
using:
------------------------------------------------------------------------------
dwgrep -e 'entry ?DW_TAG_partial_unit child* ( ?DW_AT_low_pc , ?DW_AT_high_pc , ?DW_AT_ranges )' /usr/lib/debug/**
------------------------------------------------------------------------------
BTW I think GDB already does not support the whole DW_TAG_imported_unit and
DW_TAG_partial_unit usage possibilities as specified by the DWARF standard.
I think GDB would not work if DW_TAG_imported_unit was used in some inner
level and not at the CU level (readelf -wi level <1>) - this is how DWZ is
using DW_TAG_imported_unit. Therefore I do not think further assumptions
about DW_TAG_imported_unit and DW_TAG_partial_unit usage by DWZ are a problem
for GDB.
One could save the whole .debug_line decoded PC<->lines mapping (and not just
the DW_AT_decl_file table) but:
* there are some problematic corner cases so one could do it incorrectly
* there are no real world data to really test such patch extension
* such extension could be done perfectly incrementally on top of this patch
------------------------------------------------------------------------------
benchmark - on Fedora 20 x86_64 and FSF GDB HEAD:
echo -e 'thread apply all bt\nset confirm no\nq'|./gdb -p `pidof soffice.bin` -ex 'set pagination off' -ex 'maintenance set per-command
space' -ex 'maintenance set per-command symtab' -ex 'maintenance set per-command time'
FSF GDB HEAD ("thread apply all bt"):
Command execution time: 333.693000 (cpu), 335.587539 (wall)
---sec
Space used: 1736404992 (+1477189632 for this command)
----MB
vs.
THIS PATCH ("thread apply all bt"):
Command execution time: 2.595000 (cpu), 2.607573 (wall)
-sec
Space used: 340058112 (+85917696 for this command)
--MB
FSF GDB HEAD ("thread apply all bt full"):
Command execution time: 466.751000 (cpu), 468.345837 (wall)
---sec
Space used: 2330132480 (+2070974464 for this command)
----MB
vs.
THIS PATCH ("thread apply all bt full"):
Command execution time: 18.907000 (cpu), 18.964125 (wall)
--sec
Space used: 364462080 (+110325760 for this command)
---MB
------------------------------------------------------------------------------
gdb/ChangeLog
2015-01-24 Jan Kratochvil <jan.kratochvil@redhat.com>
Fix 100x slowdown regression on DWZ files.
* dwarf2read.c (struct dwarf2_per_objfile): Add line_header_hash.
(struct line_header): Add offset and offset_in_dwz.
(dwarf_decode_lines): Add parameter decode_mapping to the declaration.
(free_line_header_voidp): New declaration.
(line_header_hash, line_header_hash_voidp, line_header_eq_voidp): New
functions.
(dwarf2_build_include_psymtabs): Update dwarf_decode_lines caller.
(handle_DW_AT_stmt_list): Use line_header_hash.
(free_line_header_voidp): New function.
(dwarf_decode_line_header): Initialize offset and offset_in_dwz.
(dwarf_decode_lines): New parameter decode_mapping, use it.
(dwarf2_free_objfile): Free line_header_hash.
In the situation described in bug 17416 [1]:
* "set print object" is on;
* The variable object is a pointer to a struct, and it contains an
invalid value (e.g. NULL, or random uninitialized value);
* The variable object (struct) has a child which is also a pointer to a
struct;
* We try to use "-var-list-children".
... an exception thrown in value_ind can propagate too far and leave an
half-built variable object, leading to a wrong state. This patch adds a
TRY_CATCH to catch it and makes value_rtti_indirect_type return NULL in
that case, meaning that the type of the pointed object could not be
found.
A test for the fix is also added.
New in v2:
* Added test.
* Restructured "catch" code.
* Added details about the bug in commit log.
gdb/Changelog:
* valops.c (value_rtti_indirect_type): Catch exception thrown by
value_ind.
gdb/testsuite/ChangeLog
* gdb.mi/mi-var-list-children-invalid-grandchild.c: New file.
* gdb.mi/mi-var-list-children-invalid-grandchild.exp: New file.
[1] https://sourceware.org/bugzilla/show_bug.cgi?id=17416
Add a flag field is_noreturn to struct func_type. Make calling_convention
a small bit field to not increase the size of the struct. Set is_noreturn
if the new GCC5/DWARF5 DW_AT_noreturn is set on a DW_TAG_subprogram.
Use this information to warn the user before doing a finish or return from
a function that does not return normally to its caller.
(gdb) finish
warning: Function endless does not return normally.
Try to finish anyway? (y or n)
(gdb) return
warning: Function does not return normally to caller.
Make endless return now? (y or n)
gdb/ChangeLog
* dwarf2read.c (read_subroutine_type): Set TYPE_NO_RETURN from
DW_AT_noreturn.
* gdbtypes.h (struct func_type): Add is_noreturn field flag. Make
calling_convention an 8 bit bit field.
(TYPE_NO_RETURN): New macro.
* infcmd.c (finish_command): Query if function does not return
normally.
* stack.c (return_command): Likewise.
gdb/testsuite/ChangeLog
* gdb.base/noreturn-return.c: New file.
* gdb.base/noreturn-return.exp: New file.
* gdb.base/noreturn-finish.c: New file.
* gdb.base/noreturn-finish.exp: New file.
include/ChangeLog
* dwarf2.def (DW_AT_noreturn): New DWARF5 attribute.
The dwarf2.h addition and the code to emit the new attribute is already in
the gcc tree.
linux_nat_is_async_p currently always returns true, even when the
target is _not_ async. That confuses
gdb_readline_wrapper/gdb_readline_wrapper_cleanup, which
force-disables target-async while the secondary prompt is active. As
a result, when gdb_readline_wrapper returns, the target is left async,
even through it was sync to begin with.
That can result in weird bugs, like the one the test added by this
commit exposes.
Ref: https://sourceware.org/ml/gdb-patches/2015-01/msg00592.html
gdb/ChangeLog:
2015-01-23 Pedro Alves <palves@redhat.com>
* linux-nat.c (linux_is_async_p): New macro.
(linux_nat_is_async_p):
(linux_nat_terminal_inferior): Check whether the target can async
instead of whether it is already async.
(linux_nat_terminal_ours): Don't check whether the target is
async.
(linux_async_pipe): Use linux_is_async_p.
gdb/testsuite/ChangeLog:
2015-01-23 Pedro Alves <palves@redhat.com>
* gdb.threads/continue-pending-after-query.c: New file.
* gdb.threads/continue-pending-after-query.exp: New file.
2015-01-22 DJ Delorie <dj@redhat.com>
* elf32-m32c.c (m32c_apply_reloc_24): New.
(m32c_elf_howto_table): Use it for R_M32C_24.
(m32c_elf_relocate_section): Handle R_M32C_24 specially.
gdb_interact is a small utility that we have found quite useful to debug
test cases.
Putting gdb_interact in a test suspends it and allows to interact with
gdb to inspect whatever you want. You can then type ">>>" to resume the
test execution. Of course, this is only for gdb devs. It wouldn't make
sense to leave a gdb_interact permanently in a test case.
When starting the interaction with the user, the script prints this
banner:
+------------------------------------------+
| Script interrupted, you can now interact |
| with by gdb. Type >>> to continue. |
+------------------------------------------+
Notes:
* When gdb is launched, the gdb_spawn_id variable (lib/gdb.exp) is
assigned -1. Given the name, I would expect it to contain the gdb
expect spawn id, which is needed for interact. I changed all places
that set gdb_spawn_id to -1 to set it to the actual gdb spawn id
instead.
* When entering the "interact" mode, the last (gdb) prompt is already
eaten by expect, so it doesn't show up on the terminal. Subsequent
prompts do appear though. We tried to print "(gdb)" just before the
interact to replace it. However, it could be misleading if you are
debugging an MI test case, it makes you think that you are typing in a
CLI prompt, when in reality it's MI. In the end I decided that since
the feature is for developers who know what they're doing and that one
is normally consciously using gdb_interact, the script doesn't need
to babysit the user.
* There are probably some quirks depending on where in the script
gdb_interact appears (e.g. it could interfere with following
commands and make them fail), but it works for most cases. Quirks can
always be fixed later.
The idea and original implementation was contributed by Anders
Granlund, a colleague of mine. Thanks to him.
gdb/testsuite/ChangeLog:
* gdb.base/statistics.exp: Assign spawn id to gdb_spawn_id.
* gdb.base/valgrind-db-attach.exp: Same.
* gdb.base/valgrind-infcall.exp: Same.
* lib/mi-support.exp (default_mi_gdb_start): Same.
* lib/prompt.exp (default_prompt_gdb_start): Same.
* lib/gdb.exp (default_gdb_spawn): Same.
(gdb_interact): New.
downstream Fedora request:
Please make it easier to find the backtrace of the crashing thread
https://bugzilla.redhat.com/show_bug.cgi?id=1024504
Currently after loading a core file GDB prints:
Core was generated by `./threadcrash1'.
Program terminated with signal SIGSEGV, Segmentation fault.
8 *(volatile int *)0=0;
(gdb) _
there is nowhere seen which of the threads had crashed. In reality GDB always
numbers that thread as #1 and it is the current thread that time. But after
dumping all the info into a file for later analysis it is no longer obvious.
'thread apply all bt' even puts the thread #1 to the _end_ of the output!!!
I find maybe as good enough and with no risk of UI change flamewar to just
sort the threads by their number. Currently they are printed as they happen
in the internal GDB list which has no advantage. Printing thread #1 as the
first one with assumed 'thread apply all bt' (after the core file is loaded)
should make the complaint resolved I guess.
On Thu, 15 Jan 2015 20:29:07 +0100, Doug Evans wrote:
No objection to sorting the list, but if thread #1 is the important one,
then a concern could be it'll have scrolled off the screen (such a
concern has been voiced in another thread in another context),
and if not lost (say it's in an emacs buffer) one would still have
to scroll back to see it.
So one *could* still want #1 to be last.
Do we want an option to choose the sort direction?
gdb/ChangeLog
2015-01-22 Jan Kratochvil <jan.kratochvil@redhat.com>
* NEWS (Changes since GDB 7.9): Add 'thread apply all' option
'-ascending'.
* thread.c (tp_array_compar_ascending, tp_array_compar): New.
(thread_apply_all_command): Parse CMD for tp_array_compar_ascending.
Sort tp_array using tp_array_compar.
(_initialize_thread): Extend thread_apply_all_command help.
gdb/doc/ChangeLog
2015-01-22 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.texinfo (Threads): Describe -ascending for thread apply all.
downstream Fedora request:
Please make it easier to find the backtrace of the crashing thread
https://bugzilla.redhat.com/show_bug.cgi?id=1024504
Currently after loading a core file GDB prints:
Core was generated by `./threadcrash1'.
Program terminated with signal SIGSEGV, Segmentation fault.
8 *(volatile int *)0=0;
(gdb) _
there is nowhere seen which of the threads had crashed. In reality GDB always
numbers that thread as #1 and it is the current thread that time. But after
dumping all the info into a file for later analysis it is no longer obvious.
'thread apply all bt' even puts the thread #1 to the _end_ of the output!!!
Should GDB always print after loading a core file what "thread" command would
print?
[Current thread is 1 (Thread 0x7fcbe28fe700 (LWP 15453))]
BTW I think it will print the thread even when loading single/non-threaded
core file when other inferior(s) exist. But that currently crashes
[Bug threads/12074] multi-inferior internal error
https://sourceware.org/bugzilla/show_bug.cgi?id=12074
plus I think that would be a correct behavior anyway.
gdb/ChangeLog
2015-01-22 Jan Kratochvil <jan.kratochvil@redhat.com>
* corelow.c (core_open): Call also thread_command.
* gdbthread.h (thread_command): New prototype moved from ...
* thread.c (thread_command): ... here.
(thread_command): Make it global.
When GDB is configured with "--without-tui --with-curses" or "--with-tui",
$prefer_curses is set to yes. But, that still doesn't mean that curses
will be used. configure will still search for the curses library, and
continue building without it. That's done here:
curses_found=no
if test x"$prefer_curses" = xyes; then
...
AC_SEARCH_LIBS(waddstr, [ncurses cursesX curses])
if test "$ac_cv_search_waddstr" != no; then
curses_found=yes
fi
fi
So if waddstr is not found, meaning curses is not really
available, even though it'd be preferred, $prefer_curses is
'yes', but $curses_found is 'no'.
So the right fix to tell whether we're linking with curses is
$curses_found=yes.
gdb/ChangeLog:
2015-01-22 Pedro Alves <palves@redhat.com>
* configure.ac [*mingw32*]: Check $curses_found instead of
$prefer_curses.
* configure: Regenerate.
* windows-termcap.c: Remove HAVE_CURSES_H, HAVE_NCURSES_H and
HAVE_NCURSES_NCURSES_H checks.
gdb/
2015-01-22 Eli Zaretskii <eliz@gnu.org>
* gdb/tui/tui.c (tui_enable) [__MINGW32__]: If the call to 'newterm'
fails with the 1st arg NULL, try again with "unknown". Don't test
the "cup" capability: it isn't supported by the Windows port of
ncurses, but the Windows console driver is still capable of
supporting TUI.
TBH while I always comment reasons for each of the compilation options in
reality I tried them all and chose that combination that needs the most simple
compile/compile-object-load.c (ld.so emulation) implementation.
gdb/ChangeLog
2015-01-22 Jan Kratochvil <jan.kratochvil@redhat.com>
* compile/compile.c (_initialize_compile): Use -fPIE for compile_args.
gdb/testsuite/ChangeLog
2015-01-22 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.compile/compile.exp (pointer to jit function): New test.
gdb/
2015-01-22 Eli Zaretskii <eliz@gnu.org>
* Makefile.in (HFILES_NO_SRCDIR): Remove ada-varobj.h.
(ALLDEPFILES): Remove irix5-nat.c. These two are part of the
reason that "make TAGS" is broken.
Original working flow has several issues:
- typo issue: "(inst >> 26) == 0x1f && ..." for checking 'stw(m)'.
- "(inst >> 6) == 0xa" needs to be "((inst >> 6) & 0xf) == 0xa".
And also need check additional store instructions:
- For absolute memory: 'stby', 'stdby'.
- For unaligned: 'stwa', 'stda'.
The original code also can be improved:
- Remove redundant double check "(inst >> 26) == 0x1b" for 'stwm'.
- Use 2 'switch' statements instead of all 'if' statements.
* hppa-tdep.c (inst_saves_gr): Fix logical working flow issues
and check additional store instructions.
PR binutils/17512
* coffcode.h (handle_COMDAT): When searching for the section
symbol, make sure that there is space left in the symbol table.
* vms-alpha.c (_bfd_vms_slurp_ehdr): Add range checks.
Found when attempting to build an ELFv2 Linux kernel. We don't
generally need a plt entry for ELFv2 got relocs, only on ifunc, just
like ppc32.
* powerpc.cc (Target_powerpc::Scan::local <got relocs>): Correct
condition for need of ifunc plt entry.
(Target_powerpc::Scan::global <got relocs>): Likewise.
PR binutils/17512
* coffcode.h (coff_set_arch_mach_hook): Check return value from
bfd_malloc.
(coff_slurp_line_table): Return FALSE if the line number
information was corrupt.
(coff_slurp_symbol_table): Return FALSE if the symbol information
was corrupt.
* mach-o.c (bfd_mach_o_bfd_copy_private_header_data): Always
initialise the fields of the dyld_info structure.
(bfd_mach_o_build_exec_seg_command): Replace assertion with an
error message and a return value.
(bfd_mach_o_layout_commands): Change the function to boolean.
Return FALSE if the function fails.
(bfd_mach_o_build_commands): Fail if bfd_mach_o_layout_commands
fails.
(bfd_mach_o_read_command): Fail if an unrecognised command is
encountered.
* peXXigen.c (_bfd_XXi_swap_aouthdr_in): Set bfd_error if the
read fails.
(slurp_symtab): Check the return from bfd_malloc.
(_bfd_XX_bfd_copy_private_bfd_data_common): Fail if the copy
encountered an error.
(_bfd_XXi_final_link_postscript): Fail if a section could not be
copied.
* peicode.h (pe_bfd_object_p): Fail if the header could not be
swapped in.
* tekhex.c (first_phase): Fail if the section is too big.
* versados.c (struct esdid): Add content_size field.
(process_otr): Use and check the new field.
(versados_get_section_contents): Check that the section exists and
that the requested data is available.
PR binutils/17512
* addr2line.c (main): Call bfd_set_error_program_name.
* ar.c (main): Likewise.
* coffdump.c (main): Likewise.
* cxxfilt.c (main): Likewise.
* dlltool.c (main): Likewise.
* nlmconv.c (main): Likewise.
* nm.c (main): Likewise.
* objdump.c (main): Likewise.
* size.c (main): Likewise.
* srconv.c (main): Likewise.
* strings.c (main): Likewise.
* sysdump.c (main): Likewise.
* windmc.c (main): Likewise.
* windres.c (main): Likewise.
* objcopy.c (main): Likewise.
(copy_relocations_in_section): Check for relocs without associated
symbol pointers.
Tests that I added in commit c05b575a8d
fails on 32-bit hosts due to differences in whitespace.
This patch updates the expected output patterns to be more accepting of
differences in whitespace, the tests should now pass.
ld/testsuite/ChangeLog:
* ld-scripts/provide-4-map.d: Update expected output.
* ld-scripts/provide-5-map.d: Likewise.
.toc1 is the second level TOC section used by gcc's -mminimal-toc. It
too should be read-only after relocation. Also, the last patch
description mentioned .sbss moving but didn't actually do that, so fix
that problem. .tocbss (whatever that is) was before .sbss previously,
so move that one too.
* emulparams/elf64ppc.sh (OTHER_SDATA_SECTIONS): Use in place of..
(OTHER_BSS_SYMBOLS): ..this.
(OTHER_PLT_RELOC_SECTIONS): Don't define.
(OTHER_GOT_RELOC_SECTIONS): Add rela.toc1 and rela.tocbss.
(OTHER_READWRITE_SECTIONS): Don't define. Move .toc1 to..
(OTHER_RELRO_SECTIONS_2): ..here.
* scripttempl/elf.sc: Move SBSS too when DATA_SDATA.
When creating a linker mapfile (using -Map=MAPFILE), we previously would
always try to evaluate the expression from a PROVIDE statement.
However, this is not always safe, consider:
PROVIDE (foo = 0x10);
PROVIDE (bar = foo);
In this example, if neither 'foo' or 'bar' is needed, then while
generating the linker mapfile evaluating the expression for 'foo' is
harmless (just the value 0x10). However, evaluating the expression for
'bar' requires the symbol 'foo', which is undefined. This used to cause
a fatal error.
This patch changes the behaviour, so that when the destination of the
PROVIDE is not defined (that is the PROVIDE is not going to provide
anything) the expression is not evaluated, and instead a special string
is displayed to indicate that the linker is discarding the PROVIDE
statement.
This change not only fixes the spurious undefined symbol error, but also
means that a user can now tell if a PROVIDE statement has provided
anything by inspecting the linker mapfile, something that could not be
done before.
ld/ChangeLog:
* ldlang.c (print_assignment): Only evaluate the expression for a
PROVIDE'd assignment when the destination is being defined.
Display a special message for PROVIDE'd symbols that are not being
provided.
ld/testsuite/ChangeLog:
* ld-scripts/provide-4.d: New file.
* ld-scripts/provide-4-map.d: New file.
* ld-scripts/provide-4.t: New file.
* ld-scripts/provide-5.d: New file.
* ld-scripts/provide-5.s: New file.
* ld-scripts/provide-5-map.d: New file.
* ld-scripts/provide-5.t: New file.
* ld-scripts/provide.exp: Run the provide-4.d and provide-5.d
tests.
Add a new option 'map' to the ld run_dump_test mechanism. When the
'map' option is given run_dump_test will ensure that there is a
-Map=MAPFILE present in the linker command line, adding one if needed.
The MAPFILE is then compared with the file passed to the new 'map'
option using the regexp_diff function. This should make it slightly
easier to write tests that check the linker mapfile output.
The only test I found that already compares mapfile content is updated
to use the new mechanism.
ld/testsuite/ChangeLog:
* ld-scripts/overlay-size.d: Add 'map' option.
* ld-scripts/overlay-size.exp: Remove manual check of mapfile.
* lib/ld-lib.exp (run_dump_test): Add support for new 'map'
option, checking linker mapfile output.
This moves .got too, which requires .sdata and .sbss to move with it,
because these sections share addressing via the toc pointer and with
small-model code must be within a 16-bit signed offset. .plt, .iplt
and .branch_lt must also be moved since they are addressed via a
32-bit offset from the toc pointer, and we might have a very large
.data section.
This change means we may have some bss style sections before the data
segment, necessitating another PT_LOAD header. Also, since _edata is
defined at the end of the data segment it's possible with an empty
.data to have _edata at the end of .plt which looks a little unusual
since .plt is a bss style section. That should only happen rarely in
real world binaries, but does occur in the ld testsuite.
ld/
* emulparams/elf64ppc.sh (BSS_PLT): Don't define.
(OTHER_READWRITE_SECTIONS): Move .branch_lt to..
(OTHER_RELRO_SECTIONS_2): ..here.
(DATA_GOT, SEPARATE_GOTPLT, DATA_SDATA, DATA_PLT,
PLT_BEFORE_GOT): Define.
* scripttempl/elf.sc: Handle DATA_SDATA and DATA_GOT/DATA_PLT/
PLT_BEFORE_GOT combination.
(DATA_GOT, SDATA_GOT): Don't define if either is already defined.
ld/testsuite/
* ld-powerpc/ambiguousv1.d,
* ld-powerpc/ambiguousv1b.d,
* ld-powerpc/ambiguousv2.d,
* ld-powerpc/ambiguousv2b.d,
* ld-powerpc/elfv2exe.d,
* ld-powerpc/elfv2so.d,
* ld-powerpc/tlsexe.r,
* ld-powerpc/tlsexetoc.r,
* ld-powerpc/tlsso.r,
* ld-powerpc/tlstocso.r: Update.
More sections can be read-only after relocation. .opd is an obvious
candidate.
* emulparams/elf64ppc.sh (OTHER_READWRITE_SECTIONS): Move .opd to..
(OTHER_RELRO_SECTIONS_2): ..here, new define.
* scripttempl/elf.sc: Add OTHER_RELRO_SECTIONS_2.
gdb/
2015-01-17 Eli Zaretskii <eliz@gnu.org>
* configure.ac [*mingw32*]: Only add windows-termcap.o to
CONFIG_OBS if not building with a curses library.
* configure: Regenerate.
* windows-termcap.c: Include defs.h. Make the whole body empty if
either one of HAVE_CURSES_H or HAVE_NCURSES_H or
HAVE_NCURSES_NCURSES_H is defined.
This fixes a MinGW warning in libiberty/strerror.c.
2015-01-19 Eli Zaretskii <eliz@gnu.org>
* strerror.c <sys_nerr, sys_errlist>: Declare only if they aren't
macros.
Running lang_common before garbage collection means slightly less work
in garbage collection code, since common symbols should no longer
appear there. It does have the side effect of keeping linker script
symbols (at least those defined outside of sections) global too,
hence some testsuite churn.
bfd/
PR 17165
* elf-bfd.h (ELF_COMMON_DEF): Note that this might be true for
linker script assignments too.
* elflink.c (elf_gc_sweep_symbol): Don't drop ELF_COMMON_DEF syms.
(bfd_elf_gc_mark_dynamic_ref_symbol): Similarly.
ld/
PR 17165
* ldlang.c (lang_process): Run lang_common before lang_gc_sections.
ld/testsuite/
* ld-gc/pr14265.d,
* ld-cris/tls-gc-68.d,
* ld-cris/tls-gc-69.d,
* ld-cris/tls-gc-70.d,
* ld-cris/tls-gc-71.d,
* ld-cris/tls-gc-75.d,
* ld-cris/tls-gc-76.d,
* ld-cris/tls-gc-79.d,
* ld-mmix/bpo-10.d,
* ld-mmix/bpo-11.d: Update.
Tests that bfd_perform_reloc doesn't freak over a NONE reloc at end
of section.
gas/
* read.c (s_reloc): Match BFD_RELOC_NONE, BFD_RELOC{8,16,32,64}.
* write.c (get_frag_for_reloc): Allow match just past end of frag.
gas/testsuite/
* gas/all/none.s,
* gas/all/none.d: New test.
* gas/all/gas.exp: Run it.