I wanted to write a linker script like this:
PROVIDE(mem_origin = 0x1000);
PROVIDE(mem_length = 0x1000);
MEMORY
{
REGION : ORIGIN = mem_origin, LENGTH = mem_length
}
....
Then when I link using this script I can optionally supply:
--defsym=mem_origin=..... --defsym=mem_length=....
to override the defaults.
And though passing `--defsym' does work, if I remove the use of
`--defsym' and just rely on the defaults I get an error:
ld-new: invalid origin for memory region REGION
Interestingly, if I make the above error non-fatal and dump a linker
map file I see that (a) REGION has origin 0x0, and length 0xffff...,
and (b) the symbol from the PROVIDE is provided.
An examination of ldlang.c:lang_process shows us what the issue is,
the origin and length of all memory regions are set as a result of a
single call to lang_do_memory_regions, this call is done after calling
open_input_bfds.
During the open_input_bfds call provide statements can be converted to
provided statements if we know that the assigned symbol is needed, but
for symbols that are only used in the memory regions we are unaware
that we need these symbols.
What I propose in this patch is to make two calls to
lang_do_memory_regions, in the first call we process the expressions
for the origin and length fields of each region, however, errors,
especially undefined symbols, will be ignored. The origin and length
values are not updated. However, by evaluating the expressions any
symbols we need will be added to the symbol table.
Now when we call open_input_bfds, when we process the provide
statements, we will see that the assigned symbol is needed add its new
value to the symbol table.
Finally we reach the original call to lang_do_memory_regions, in
this (now second) call we again process the expressions, and this time
update the origin and length values. Any errors encountered now are
reported to the user.
ld/ChangeLog:
* ldlang.c (lang_process): Add extra call to
lang_do_memory_regions, and pass parameter.
(lang_do_memory_regions): Add parameter, only define origin and
length when requested. Reindent.
* testsuite/ld-scripts/provide-10.d: New file.
* testsuite/ld-scripts/provide-10.map: New file.
* testsuite/ld-scripts/provide-11.d: New file.
* testsuite/ld-scripts/provide-11.map: New file.
* testsuite/ld-scripts/provide-12.d: New file.
* testsuite/ld-scripts/provide-12.map: New file.
* testsuite/ld-scripts/provide-9.d: New file.
* testsuite/ld-scripts/provide-9.map: New file.
* testsuite/ld-scripts/provide-9.t: New file.
The ordering of command line options --defsym and -T is important,
however, the description of --defsym in the manual doesn't mention
this.
This commit adds more text to the description of --defsym to try and
explain this ordering requirement.
ld/ChangeLog:
* ld.texi (Options): Extend the description of --defsym.
Some instructions can be emitted (dwarf2_emit_insn is called) before the
first .file <NUMBER> directive has been seen, which allocates the input
file as the first file entry. Reuse the input file entry in the file
table.
PR gas/25878
PR gas/26740
* dwarf2dbg.c (file_entry): Remove auto_assigned.
(assign_file_to_slot): Remove the auto_assign argument.
(allocate_filenum): Updated.
(allocate_filename_to_slot): Reuse the input file entry in the
file table.
(dwarf2_where): Replace as_where with as_where_physical.
* testsuite/gas/i386/dwarf5-line-1.d: New file.
* testsuite/gas/i386/dwarf5-line-1.s: Likewise.
* testsuite/gas/i386/i386.exp: Run dwarf5-line-1.
PR 26626
* ldmain.c (undefined_symbol): If an error handlign script is
available, call it.
* ldfile.c (error_handling_script): Declare.
(ldfile_open_file): If a library cannot be found and an error
handling script is available, call it.
* ldmain.h (error_handling_script): Prototype.
* ldlex.h (OPTION_ERROR_HANDLING_SCRIPT): Define.
* lexsup.c (ld_options): Add --error-handling-script.
(parse_args): Add support for --errror-handling-script.
* ld.texi: Document the new feature.
* configure.ac: Add --error-handling-script option to disable
support for the new feature.
* NEWS: Mention the new feature.
* config.in: Regenerate.
* configure: Regenerate.
Commit 5b7d00507b adds a mention at gdb_breakpoint of a supported argument
"passfail". There's no corresponding argument handling though.
Remove the mention of the "passfail" argument.
gdb/testsuite/ChangeLog:
2020-10-16 Tom de Vries <tdevries@suse.de>
* lib/gdb.exp (gdb_breakpoint): Remove mention of "passfail".
I noticed that an abort when setting a breakpoint does not result in more
than:
...
(gdb) break 27^M
FAIL: gdb.a/b.exp: setting breakpoint at 27 (eof)
...
Handle this more verbosely, as is done in gdb_test_multiple, such that we have
instead:
...
(gdb) break 27^M
ERROR: GDB process no longer exists
GDB process exited with wait status 29309 exp9 0 0 CHILDKILLED SIGABRT SIGABRT
UNRESOLVED: gdb.a/b.exp: setting breakpoint at 27 (eof)
...
Tested on x86_64-linux.
gdb/testsuite/ChangeLog:
2020-10-16 Tom de Vries <tdevries@suse.de>
* lib/gdb.exp (gdb_breakpoint): Handle eof as in gdb_test_multiple.
For the ifunc symbol, which is referenced by GOT rather than PLT relocs,
we should add the dynamic reloc (usually IRELATIVE) into the .rel.iplt
when generating the static executable. But if we use riscv_elf_append_rela
to add the dynamic relocs into .rela.iplt, this may cause the overwrite
problem.
The reason is that we don't handle the `reloc_index` of .rela.iplt, but
the riscv_elf_append_rela adds the relocs to the place that are calculated
from the reloc_index (in seqential). Therefore, we may overwrite the
dynamic relocs when the `reloc_index` of .rela.iplt isn't handled correctly.
One solution is that we can add these dynamic relocs (GOT ifunc) from
the last of .rela.iplt section. But I'm not sure if it is the best way.
bfd/
* elfnn-riscv.c (riscv_elf_link_hash_table): Add last_iplt_index.
(riscv_elf_size_dynamic_sections): Initialize the last_iplt_index.
(riscv_elf_relocate_section): Use riscv_elf_append_rela.
(riscv_elf_finish_dynamic_symbol): If the use_elf_append_rela is
false, then we should add the dynamic relocs from the last of
the .rela.iplt, and don't use the riscv_elf_append_rela to add.
ld/
* testsuite/ld-riscv-elf/ifunc-plt-got-overwrite.s: New testcase.
* testsuite/ld-riscv-elf/ifunc-plt-got-overwrite.d: Likewise.
* testsuite/ld-riscv-elf/ifunc-plt-got-overwrite-exe.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-plt-got-overwrite-pic.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-plt-got-overwrite-pie.rd: Likewise.
* testsuite/ld-riscv-elf/ld-riscv-elf.exp: Updated.
Generally, glibc dynamic linker should have two ways to deal with ifunc
- one is to handle the IRELATIVE relocations for the non-preemtive ifunc
symbols, the other is to handle the R_RISCV_32/64 and R_RISCV_JUMP_SLOT
relocations with the STT_IFUNC preemtive symbols. No matter which method
is used, both of them should get the resolved ifunc symbols at runtime.
Therefore, linker needs to generate the correct dynamic relocations for
ifunc to make sure the the dynamic linker works well. For now, there are
thirteen relocations are supported for ifunc in GNU ld,
* R_RISCV_CALL and R_RISCV_CALL_PLT:
The RISC-V compiler won't generate R_RISCV_JAL directly to jump to an
ifunc. Besides, we disable the relaxations for the relocation referenced
to ifunc, so just handling the R_RISCV_CALL and R_RISCV_CALL_PLT should be
enough. Linker should generate a .plt entry and a .got.plt entry for it,
and also needs to insert a dynamic IRELATIVE in the .got.plt enrty, or
insert a R_RISCV_JUMP_SLOT when generating shared library.
* R_RISCV_PCREL_HI20 and R_RISCV_PCREL_LO12_I/S:
LA/LLA pattern with local fPIC ifunc symbol, or any non-PIC ifunc symbol.
The PC-relative relocation. The current linker will deal with them in
the same way as R_RISCV_CALL_PLT.
* R_RISCV_GOT_HI20 and R_RISCV_PCREL_LO12_I/S:
LA pattern with global PIC ifunc symbol. Linker should insert a dynamic
IRELATIVE in the .got entry, or insert a R_RISCV_32/64 when generating
shared library.
* R_RISCV_32 and R_RISCV_64:
Store the ifunc symbol into the data section. Linker should insert a
dynamic IRELATIVE in the data section, or insert a R_RISCV_32/64 when
generating shared library.
* R_RISCV_HI20 and R_RISCV_LO12_I/S:
The LUI + ADDI/LW/SW patterns. The absolute access relocation. The
medlow model without the -fPIC compiler option should generate them.
The ld ifunc testsuites "Build pr23169a" and "Build pr23169d" need the
relocations, they are in the ld/testsuite/ld-ifunc/, and need compiler
support.
However, we also made some optimizations with reference to x86,
* If GOT and PLT relocations refer to the same ifunc symbol when generating
pie, then they can actually share a .got entry without creating two entries
to store the same value and relocation.
* If GOT, PLT and DATA relocations refer to the same ifunc symbol when
generating position dependency executable, then linker will fill the address
of .plt entry into the corresponding .got entry and data section, without
insert any dynamic relocations for the GOT and DATA relocations.
For the ifunc testcases, there are three types of them,
1. ifunc-reloc-*: Only check the single type of relocation refers to
ifunc symbol.
* ifunc-reloc-call: R_RISCV_CALL and R_RISCV_CALL_PLT.
* ifunc-reloc-data: R_RISCV_32 and R_RISCV_64.
* ifunc-reloc-got: R_RISCV_GOT_HI20 and R_RISCV_PCREL_LO_I/S.
* ifunc-reloc-pcrel: R_RISCV_PCREL_HI20 and R_RISCV_PCREL_LO_I/S.
2. ifunc-[nonplt|plt]-*: If we don't have PLT relocs, then don't need to
create the PLT and it's .plt entries.
* ifunc-nonplt: Combine R_RISCV_GOT_HI20 and R_RISCV_32/64.
* ifunc-plt: Combine all ifunc relocations.
3. ifunc-seperate-*: If we link the ifunc caller and resolver into the
same module (link the objects), then the results are the same as the
ifunc-reloc-* and ifunc-[noplt|plt]-* testcases. Consider the cases that
the ifunc callers and resolver are in the different modules, that is, we
compile the ifunc resolver to the shared library first, and then link it
with the ifunc callers. The output of ifunc callers should be the same as
the normal STT_FUNC cases, and the shared ifunc resolver should define the
symbols as STT_IFUNC.
The R_RISCV_PCREL_HI20 reloc is special. It should be linked and resolved
locally, so if the ifunc resolver is defined in other modules (other shared
libraries), then the R_RISCV_PCREL_HI20 is unresolvable, and linker should
issue an unresolvable reloc error.
bfd/
* elfnn-riscv.c: Include "objalloc.h" since we need objalloc_alloc.
(riscv_elf_link_hash_table): Add loc_hash_table and loc_hash_memory
for local STT_GNU_IFUNC symbols.
(riscv_elf_got_plt_val): Removed.
(riscv_elf_local_htab_hash, riscv_elf_local_htab_eq): New functions.
Use to compare local hash entries.
(riscv_elf_get_local_sym_hash): New function. Find a hash entry for
local symbol, and create a new one if needed.
(riscv_elf_link_hash_table_free): New function. Destroy an riscv
elf linker hash table.
(riscv_elf_link_hash_table_create): Create hash table for local ifunc.
(riscv_elf_check_relocs): Create a fake global symbol to track the
local ifunc symbol. Add support to check and handle the relocations
reference to ifunc symbols.
(allocate_dynrelocs): Let allocate_ifunc_dynrelocs and
allocate_local_ifunc_dynrelocs to handle the ifunc symbols if they
are defined and referenced in a non-shared object.
(allocate_ifunc_dynrelocs): New function. Allocate space in .plt,
.got and associated reloc sections for ifunc dynamic relocs.
(allocate_local_ifunc_dynrelocs): Likewise, but for local ifunc
dynamic relocs.
(riscv_elf_relocate_section): Add support to handle the relocation
referenced to ifunc symbols.
(riscv_elf_size_dynamic_sections): Updated.
(riscv_elf_adjust_dynamic_symbol): Updated.
(riscv_elf_finish_dynamic_symbol): Finish up the ifunc handling,
including fill the PLT and GOT entries for ifunc symbols.
(riscv_elf_finish_local_dynamic_symbol): New function. Called by
riscv_elf_finish_dynamic_symbol to handle the local ifunc symbols.
(_bfd_riscv_relax_section): Don't do the relaxation for ifunc.
* elfxx-riscv.c: Add R_RISCV_IRELATIVE.
* configure.ac: Link elf-ifunc.lo to use the generic ifunc support.
* configure: Regenerated.
include/
* elf/riscv.h: Add R_RISCV_IRELATIVE to 58.
ld/
* emulparams/elf32lriscv-defs.sh: Add IREL_IN_PLT.
* testsuite/ld-ifunc/ifunc.exp: Enable ifunc tests for RISC-V.
* testsuite/ld-riscv-elf/ld-riscv-elf.exp (run_dump_test_ifunc):
New dump test for ifunc. There are two arguments, 'target` and
`output`. The `target` is rv32 or rv64, and the `output` is used
to choose which output you want to test (exe, pie or .so).
* testsuite/ld-riscv-elf/ifunc-reloc-call-01.s: New testcase.
* testsuite/ld-riscv-elf/ifunc-reloc-call-01.d: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-call-01-exe.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-call-01-pic.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-call-01-pie.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-call-02.s: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-call-02.d: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-call-02-exe.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-call-02-pic.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-call-02-pie.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-data.s: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-data.d: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-data-exe.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-data-pic.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-data-pie.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-got.s: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-got.d: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-got-exe.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-got-pic.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-got-pie.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-pcrel.s: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-pcrel.d: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-pcrel-exe.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-pcrel-pic.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-reloc-pcrel-pie.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-nonplt.s: Likewise.
* testsuite/ld-riscv-elf/ifunc-nonplt.d: Likewise.
* testsuite/ld-riscv-elf/ifunc-nonplt-exe.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-nonplt-pic.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-nonplt-pie.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-plt-01.s: Likewise.
* testsuite/ld-riscv-elf/ifunc-plt-01.d: Likewise.
* testsuite/ld-riscv-elf/ifunc-plt-01-exe.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-plt-01-pic.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-plt-01-pie.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-plt-02.s: Likewise.
* testsuite/ld-riscv-elf/ifunc-plt-02.d: Likewise.
* testsuite/ld-riscv-elf/ifunc-plt-02-exe.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-plt-02-pic.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-plt-02-pie.rd: Likewise.
* testsuite/ld-riscv-elf/ifunc-seperate-resolver.s: Likewise.
* testsuite/ld-riscv-elf/ifunc-seperate-caller.s: Likewise.
* testsuite/ld-riscv-elf/ifunc-seperate-exe.d: Likewise.
* testsuite/ld-riscv-elf/ifunc-seperate-pic.d: Likewise.
* testsuite/ld-riscv-elf/ifunc-seperate-pie.d: Likewise.
* testsuite/ld-riscv-elf/ifunc-seperate-caller-pcrel.s: Likewise.
* testsuite/ld-riscv-elf/ifunc-seperate-pcrel-pic.d: Likewise.
* testsuite/ld-riscv-elf/ifunc-seperate-pcrel-pie.d: Likewise.
Casts should be avoided if at all possible, and in particular the C
standard doesn't promise that function pointers can be cast to void*
or vice-versa. It is only mentioned under J.5 Common extensions,
saying "The following extensions are widely used in many systems, but
are not portable to all implementations."
* elf32-arc.c (replace_func): Correct return type.
(get_replace_function): Use a replace_func function pointer rather
than void*. Update associated ARC_RELOC_HOWTO define.
Prompted by two occurrences of -Wmisleading-indentation warnings.
* elf32-cr16.c: Formatting.
(cr16_elf_final_link_relocate): Sign extend rather than clumsy
"add or subtract" of offset value. Simplify range checks. Move
common code out of "if" branches. Don't refetch insn fields
needlessly.
The previous sanity check allowed a ld on the HA reloc and addis
on the LO_DS.
* elf64-ppc.c (ppc64_elf_relocate_section): Tighten sanity check
on R_PPC64_GOT_LO_DS and R_PPC64_GOT_HA instructions.
After commit:
commit 361cb21935
Date: Tue Oct 6 10:09:06 2020 +0100
gnulib: Ensure all libraries are used when building gdb/gdbserver
We now get an error when, at the top level of the build tree, we do
'make distclean'.
The reason for this is that the gnulib directory is cleaned before the
gdb directory, cleaning gnulib deletes Makefile.gnulib.inc from the
gnulib build directory, which is currently pulled in by the gdb
Makefile.in using 'include'.
This commit adds a dependency between distclean-gnulib and both
distclean-gdb and distclean-gdbserver. This means that gdb and
gdbserver will be cleaned before gnulib, as a result the
Makefile.gnulib.inc file should exist when needed.
ChangeLog:
* Makefile.in: Rebuild.
* Makefile.def: Make distclean-gnulib depend on distclean-gdb and
distclean-gdbserver.
The test-case gdb.ada/mi_catch_ex.exp tests two scenarios.
The two scenarios are separated by:
- a mi_run_to_main (before commit b75d55d4d2 "Eliminate mi_run_to_main,
introduce mi_clean_restart")
- a mi_runto_main (after that commit)
The now removed mi_run_to_main contained a mi_delete_breakpoints, while
mi_runto_main does not, which causes FAILs in the second scenario.
Fix this by adding the missing mi_delete_breakpoints in the test-case, and
likewise in gdb.ada/mi_catch_ex_hand.exp.
Reg-tested on x86_64-linux.
gdb/testsuite/ChangeLog:
2020-10-14 Tom de Vries <tdevries@suse.de>
PR testsuite/26732
* gdb.ada/mi_catch_ex.exp: Do mi_delete_breakpoints before running
scenario 2.
* gdb.ada/mi_catch_ex_hand.exp: Same.
Starting commit bb2a67773c "Use a std::vector in target_section_table" we run
into:
...
ERROR: GDB process no longer exists
GDB process exited with wait status 22239 exp12 0 0 CHILDKILLED SIGABRT
UNRESOLVED: gdb.base/exec-invalid-sysroot.exp: continue to exec catchpoint
...
which reproduces as:
...
Thread 1 "gdb" received signal SIGSEGV, Segmentation fault.
solib_contains_address_p (address=4196111, solib=0x1dd9970)
at /home/vries/gdb_versions/devel/src/gdb/solib.c:1120
1120 for (target_section &p : solib->sections->sections)
(gdb) p solib->sections->sections
Cannot access memory at address 0x0
...
Fix this by handling solib->sections == nullptr in solib_contains_address_p.
Build and reg-tested on x86_64-linux.
gdb/ChangeLog:
2020-10-14 Tom de Vries <tdevries@suse.de>
PR gdb/26733
* solib.c (solib_contains_address_p): Handle
'solib->sections == nullptr'.
Rename VexOpcode to OpcodePrefix so that OpcodePrefix can be used for
regular encoding prefix.
gas/
* config/tc-i386.c (build_vex_prefix): Replace vexopcode with
opcodeprefix.
(build_evex_prefix): Likewise.
(is_any_vex_encoding): Don't check vexopcode.
(output_insn): Handle opcodeprefix.
opcodes/
* i386-gen.c (opcode_modifiers): Replace VexOpcode with
OpcodePrefix.
* i386-opc.h (VexOpcode): Renamed to ...
(OpcodePrefix): This.
(PREFIX_NONE): New.
(PREFIX_0X66): Likewise.
(PREFIX_0XF2): Likewise.
(PREFIX_0XF3): Likewise.
* i386-opc.tbl (Prefix_0X66): New.
(Prefix_0XF2): Likewise.
(Prefix_0XF3): Likewise.
Replace VexOpcode= with OpcodePrefix=. Use Prefix_0X66 on xorpd.
Use Prefix_0XF3 on cvtdq2pd. Use Prefix_0XF2 on cvtpd2dq.
* i386-tbl.h: Regenerated.
Since we now have mi_runto_main which is like runto_main, eliminate
mi_run_to_main, in favor of a new MI clean_restart counterpart --
mi_clean_restart -- and mi_runto_main.
This makes MI testcases look a bit more like CLI testcases.
gdb/testsuite/ChangeLog:
* lib/mi-support.exp (mi_clean_restart): New.
(mi_run_to_main): Delete.
All callers adjust to use mi_clean_restart / mi_runto_main.
Change-Id: I34920bab4fea1f23fb752928c2969c1f6ad714b6
Similar to the previous patch, but this time add "-q" to tests that do
"break main", "list main", etc. explicitly.
gdb/testsuite/ChangeLog:
* config/monitor.exp: Use "list -q".
* gdb.arch/gdb1558.exp: Use "break -q".
* gdb.arch/i386-permbkpt.exp: Use "break -q".
* gdb.arch/i386-prologue-skip-cf-protection.exp: Use "break -q".
* gdb.base/break.exp: Use "break -q", "list -q" and "tbreak -q".
* gdb.base/commands.exp: Use "break -q".
* gdb.base/condbreak.exp: Use "break -q".
* gdb.base/ctf-ptype.exp: Use "list -q".
* gdb.base/define.exp: Use "break -q".
* gdb.base/del.exp: Use "break -q".
* gdb.base/fullname.exp: Use "break -q".
* gdb.base/hbreak-in-shr-unsupported.exp: Use "hbreak -q".
* gdb.base/hbreak-unmapped.exp: Use "hbreak -q".
* gdb.base/hbreak2.exp: Use "hbreak -q" and "list -q".
* gdb.base/hw-sw-break-same-address.exp: Use "break -q" and
"hbreak -q".
* gdb.base/included.exp: Use "list -q".
* gdb.base/label.exp: Use "break -q".
* gdb.base/lineinc.exp: Use "break -q".
* gdb.base/list.exp: Use "list -q".
* gdb.base/macscp.exp: Use "list -q".
* gdb.base/pending.exp: Use "break -q".
* gdb.base/prologue-include.exp: Use "break -q".
* gdb.base/ptype.exp: Use "list -q".
* gdb.base/sepdebug.exp: Use "break -q", "list -q" and "tbreak -q".
* gdb.base/server-del-break.exp: Use "break -q".
* gdb.base/style.exp: Use "break -q".
* gdb.base/symbol-without-target_section.exp: Use "list -q".
* gdb.base/watchpoint-reuse-slot.exp: Use "hbreak -q".
* gdb.cp/exception.exp: Use "tbreak -q".
* gdb.dwarf2/dw2-error.exp: Use "break -q".
* gdb.dwarf2/fission-mix.exp: Use "break -q".
* gdb.dwarf2/fission-reread.exp: Use "break -q".
* gdb.dwarf2/pr13961.exp: Use "break -q".
* gdb.linespec/explicit.exp: Use "list -q".
* gdb.linespec/linespec.exp: Use "break -q".
* gdb.mi/mi-simplerun.exp: Use "--qualified".
* gdb.python/py-mi-objfile-gdb.py: Use "list -q".
* gdb.server/bkpt-other-inferior.exp: Use "break -q".
* gdb.server/connect-without-multi-process.exp: Use "break -q".
* gdb.trace/change-loc.exp: Use "break -q".
* gdb.trace/pending.exp: Use "break -q".
* gdb.tui/basic.exp: Use "list -q".
* gdb.tui/list-before.exp: Use "list -q".
* gdb.tui/list.exp: Use "list -q".
* lib/gdb.exp (gdb_has_argv0): Use "break -q".
Change-Id: Iab9408e90ed71cbb111cd737d2d81b5ba8adb108
In some runtimes, there may be a "main" function in some class or
namespace. The breakpoint created by runto_main may therefore have
unexpected locations on some other functions than the actual main.
These breakpoint locations can unexpectedly get hit during tests and
lead to failures.
I saw this while playing with AMD's ROCm toolchain -- I wrote a board
file to run the testsuite against device kernels. There, the runtime
calls a "main" function before the device kernel code is reached:
Thread 4 "bit_extract" hit Breakpoint 1, 0x00007ffeea140960 in lld:🧝:LinkerDriver::main(llvm::ArrayRef<char const*>) () from /opt/rocm/lib/libamd_comgr.so.1
(gdb) bt
#0 0x00007ffeea140960 in lld:🧝:LinkerDriver::main(llvm::ArrayRef<char const*>) () from /opt/rocm/lib/libamd_comgr.so.1
#1 0x00007ffeea2257a5 in lld:🧝:link(llvm::ArrayRef<char const*>, bool, llvm::raw_ostream&, llvm::raw_ostream&) () from /opt/rocm/lib/libamd_comgr.so.1
#2 0x00007ffeea1bc374 in COMGR::linkWithLLD(llvm::ArrayRef<char const*>, llvm::raw_ostream&, llvm::raw_ostream&) () from /opt/rocm/lib/libamd_comgr.so.1
#3 0x00007ffeea1bfb09 in COMGR::InProcessDriver::execute(llvm::ArrayRef<char const*>) () from /opt/rocm/lib/libamd_comgr.so.1
#4 0x00007ffeea1c4da9 in COMGR::AMDGPUCompiler::linkToExecutable() () from /opt/rocm/lib/libamd_comgr.so.1
#5 0x00007ffeea1fde20 in dispatchCompilerAction(amd_comgr_action_kind_s, COMGR::DataAction*, COMGR::DataSet*, COMGR::DataSet*, llvm::raw_ostream&) () from /opt/rocm/lib/libamd_comgr.so.1
#6 0x00007ffeea203a87 in amd_comgr_do_action () from /opt/rocm/lib/libamd_comgr.so.1
...
To avoid that, pass "qualified" to runto, in runto_main, so that
gdb_breakpoint ends up creating a breakpoint with -qualified. This
avoids creating breakpoints locations for other unrelated "main"
functions.
Note: I first tried making runto itself use "-qualified", but that
caused regressions in the gdb.ada/ tests, which use runto without
specifying the whole fully-qualified function name (i.e., without the
package). So I end up restricting the -qualified to
runto_main/mi_runto_main.
The gdb.base/ui-redirect.exp change is necessary because that testcase
is looking at what "save breakpoint" generates.
gdb/testsuite/ChangeLog:
* gdb.base/ui-redirect.exp: Expect "break -qualified main" in
saved breakpoints file.
* gdb.guile/scm-breakpoint.exp: Expect "-qualified main" when
inspecting breakpoint list.
* lib/gdb.exp (runto_main): Add "qualified" to options.
* lib/mi-support.exp (mi_runto_helper): Add 'qualified' parameter,
and handle it.
(mi_runto_main): Pass 1 as qualified argument.
Change-Id: I51468359ab0a518f05f7c0394c97f7e33b45fe69
This adds an mi_runto_main routine, very much like the runto_main CLI
counterpart.
Note there's already a mi_run_to_main (extra underscore in "run_to"),
but unlike its intro comment says, that does more than the CLI's
runto_main -- it also starts GDB. I would like to eliminate that
other one by introducing a mi_clean_restart function instead. That is
done later in the series.
gdb/testsuite/ChangeLog:
* lib/mi-support.exp (mi_runto_main): New proc.
(mi_run_to_main): Use it.
* gdb.mi/mi-catch-cpp-exceptions.exp: Likewise.
* gdb.mi/mi-var-cmd.exp: Likewise.
* gdb.mi/mi-var-invalidate.exp: Likewise.
* mi-var-list-children-invalid-grandchild.exp: Likewise.
* gdb.mi/mi2-amd64-entry-value.exp: Likewise.
* gdb.mi/new-ui-mi-sync.exp: Likewise.
* gdb.mi/user-selected-context-sync.exp: Likewise.
* gdb.opt/inline-cmds.exp: Likewise.
* gdb.python/py-framefilter-mi.exp: Likewise.
* gdb.python/py-mi.exp: Likewise.
Change-Id: I2e49ca7b0b61cea57c1202e5dfa32417e6a4403d
Debugging with "maintenance set target-async off" on Linux has been
broken since 5b6d1e4fa4 ("Multi-target support").
The issue is easy to reproduce:
$ ./gdb -q --data-directory=data-directory -nx ./test
Reading symbols from ./test...
(gdb) maintenance set target-async off
(gdb) start
Temporary breakpoint 1 at 0x1151: file test.c, line 5.
Starting program: /home/simark/build/binutils-gdb/gdb/test
... and it hangs there.
The difference between pre-5b6d1e4fa4f and 5b6d1e4fa4 is that
fetch_inferior_event now calls target_wait with TARGET_WNOHANG for
non-async-capable targets, whereas it didn't before.
For non-async-capable targets, this is how it's expected to work when
resuming execution:
1. we call resume
2. the infrun async handler is marked in prepare_to_wait, to immediately
wake up the event loop when we get back to it
3. fetch_inferior_event calls the target's wait method without
TARGET_WNOHANG, effectively blocking until the target has something
to report
However, since we call the target's wait method with TARGET_WNOHANG,
this happens:
1. we call resume
2. the infrun async handler is marked in prepare_to_wait, to immediately
wake up the event loop when we get back to it
3. fetch_inferior_event calls the target's wait method with
TARGET_WNOHANG, the target has nothing to report yet
4. we go back to blocking on the event loop
5. SIGCHLD finally arrives, but the event loop is not woken up, because
we are not in async mode. Normally, we should have been stuck in
waitpid the SIGCHLD would have unblocked us.
We end up in this situation because these two necessary conditions are
met:
1. GDB uses the TARGET_WNOHANG option with a target that can't do async.
I don't think this makes sense. I mean, it's technically possible,
the doc for TARGET_WNOHANG is:
/* Return immediately if there's no event already queued. If this
options is not requested, target_wait blocks waiting for an
event. */
TARGET_WNOHANG = 1,
... which isn't in itself necessarily incompatible with synchronous
targets. It could be possible for a target to support non-blocking
polls, while not having a way to asynchronously wake up the event
loop, which is also necessary to support async. But as of today,
we don't expect GDB and sync targets to work this way.
2. The linux-nat target, even in the mode where it emulates a
synchronous target (with "maintenance set target-async off") respects
TARGET_WNOHANG. Other non-async targets, such as windows_nat_target,
simply don't check / support TARGET_WNOHANG, so their wait method is
always blocking.
Fix the first issue by avoiding using TARGET_WNOHANG on non-async
targets, in do_target_wait_1. Add an assert in target_wait to verify it
doesn't happen.
The new test gdb.base/maint-target-async-off.exp is a simple test that
just tries running to main and then to the end of the program, with
"maintenance set target-async off".
gdb/ChangeLog:
PR gdb/26642
* infrun.c (do_target_wait_1): Clear TARGET_WNOHANG if the
target can't do async.
* target.c (target_wait): Assert that we don't pass
TARGET_WNOHANG to a target that can't async.
gdb/testsuite/ChangeLog:
PR gdb/26642
* gdb.base/maint-target-async-off.c: New test.
* gdb.base/maint-target-async-off.exp: New test.
Change-Id: I69ad3a14598863d21338a8c4e78700a58ce7ad86
Currently it does not add any value.
The netbsd_tdesc local variable is no longer needed. Remove it.
The tdesc value is set by the low target now.
gdbserver/ChangeLog:
* netbsd-low.cc (netbsd_tdesc): Remove.
(netbsd_add_process): Likewise.
(netbsd_process_target::create_inferior): Update.
Skip incremental_test_2, incremental_test_3, incremental_test_4,
incremental_test_5, incremental_copy_test, incremental_common_test_1
and incremental_comdat_test_1 when -fcf-protection is used to compile
gold since gold doesn't properly support -fcf-protection on Intel CET
enabled OS.
Also skip incremental_copy_test and incremental_comdat_test_1 for GCC 9
or later since they failed with GCC 9 or later.
PR gold/23539
* configure.ac: Check for GCC 9 or later and for -fcf-protection.
* configure: Regenerated.
* testsuite/Makefile.am (check_PROGRAMS): Skip incremental_test_2,
incremental_test_3, incremental_test_4, incremental_test_5,
incremental_copy_test, incremental_common_test_1 and
incremental_comdat_test_1 for -fcf-protection. Also Skip
incremental_copy_test and incremental_comdat_test_1 for GCC 9 or
later.
* testsuite/Makefile.in: Regenerated.
This patch updates GNU_PROPERTY_X86_XXX macros for gold:
1. GNU_PROPERTY_X86_UINT32_AND_XXX: A 4-byte unsigned integer property.
A bit is set if it is set in all relocatable inputs:
#define GNU_PROPERTY_X86_UINT32_AND_LO 0xc0000002
#define GNU_PROPERTY_X86_UINT32_AND_HI 0xc0007fff
2. GNU_PROPERTY_X86_UINT32_OR_XXX: A 4-byte unsigned integer property.
A bit is set if it is set in any relocatable inputs:
#define GNU_PROPERTY_X86_UINT32_OR_LO 0xc0008000
#define GNU_PROPERTY_X86_UINT32_OR_HI 0xc000ffff
3. GNU_PROPERTY_X86_UINT32_OR_AND_XXX: A 4-byte unsigned integer property.
A bit is set if it is set in any relocatable inputs and the property is
present in all relocatable inputs:
#define GNU_PROPERTY_X86_UINT32_OR_AND_LO 0xc0010000
#define GNU_PROPERTY_X86_UINT32_OR_AND_HI 0xc0017fff
4. GNU_PROPERTY_X86_FEATURE_2_NEEDED, GNU_PROPERTY_X86_FEATURE_2_USED
and GNU_PROPERTY_X86_FEATURE_2_XXX bits.
GNU_PROPERTY_X86_FEATURE_1_AND is unchanged. GNU_PROPERTY_X86_ISA_1_USED
and GNU_PROPERTY_X86_ISA_1_NEEDED are updated to better support targeted
processors since GNU_PROPERTY_X86_ISA_1_?86 aren't isn't very useful.
A new set of GNU_PROPERTY_X86_ISA_1_XXX bits are defined. The previous
GNU_PROPERTY_X86_ISA_1_XXX macros are deprecated and renamed to
GNU_PROPERTY_X86_COMPAT_ISA_1_XXX and GNU_PROPERTY_X86_COMPAT_2_ISA_1_XXX.
elfcpp/
* elfcpp.h (GNU_PROPERTY_X86_ISA_1_USED): Renamed to ...
(GNU_PROPERTY_X86_COMPAT_ISA_1_USED): This.
(GNU_PROPERTY_X86_ISA_1_NEEDED): Renamed to ...
(GNU_PROPERTY_X86_COMPAT_ISA_1_NEEDED): This.
(GNU_PROPERTY_X86_UINT32_AND_LO): New.
(GNU_PROPERTY_X86_UINT32_AND_HI): Likewise.
(GNU_PROPERTY_X86_UINT32_OR_LO): Likewise.
(GNU_PROPERTY_X86_UINT32_OR_HI): Likewise.
(GNU_PROPERTY_X86_UINT32_OR_AND_LO): Likewise.
(GNU_PROPERTY_X86_UINT32_OR_AND_HI): Likewise.
(GNU_PROPERTY_X86_COMPAT_2_ISA_1_NEEDED): New.
(GNU_PROPERTY_X86_COMPAT_2_ISA_1_NEEDED): Likewise.
(GNU_PROPERTY_X86_FEATURE_1_AND): Updated to
(GNU_PROPERTY_X86_UINT32_AND_LO + 0).
(GNU_PROPERTY_X86_ISA_1_NEEDED): New. Defined to
GNU_PROPERTY_X86_UINT32_OR_LO + 2.
(GNU_PROPERTY_X86_FEATURE_2_NEEDED): New. Defined to
(GNU_PROPERTY_X86_UINT32_OR_LO + 1).
(GNU_PROPERTY_X86_ISA_1_USED): New. Defined to
GNU_PROPERTY_X86_UINT32_OR_AND_LO + 2.
(GNU_PROPERTY_X86_FEATURE_2_USED): New. Defined to
(GNU_PROPERTY_X86_UINT32_OR_AND_LO + 1).
gold/
* x86_64.cc (Target_x86_64::Target_x86_64): Initialize
feature_2_used_, feature_2_needed_ and object_feature_2_used_.
(Target_x86_64::feature_2_used_): New data member.
(Target_x86_64::feature_2_needed_): Likewise.
(Target_x86_64::object_isa_1_used_): Likewise.
(Target_x86_64::record_gnu_property): Support
GNU_PROPERTY_X86_COMPAT_ISA_1_USED,
GNU_PROPERTY_X86_COMPAT_ISA_1_NEEDED,
GNU_PROPERTY_X86_COMPAT_2_ISA_1_USED,
GNU_PROPERTY_X86_COMPAT_2_ISA_1_NEEDED,
GNU_PROPERTY_X86_FEATURE_2_USED and
GNU_PROPERTY_X86_FEATURE_2_NEEDED.
(Target_x86_64::merge_gnu_properties): Merge FEATURE_2_USED bits.
Initialize object_feature_2_used_.
(Target_x86_64::do_finalize_gnu_properties): Support
GNU_PROPERTY_X86_FEATURE_2_USED and
GNU_PROPERTY_X86_FEATURE_2_NEEDED.
* testsuite/gnu_property_a.S (GNU_PROPERTY_X86_ISA_1_USED): Set
to 0xc0010002.
(GNU_PROPERTY_X86_ISA_1_NEEDED): Set to 0xc0008002.
* testsuite/gnu_property_b.S (GNU_PROPERTY_X86_ISA_1_USED): Set
to 0xc0010002.
(GNU_PROPERTY_X86_ISA_1_NEEDED): Set to 0xc0008002.
* testsuite/gnu_property_c.S (GNU_PROPERTY_X86_ISA_1_USED): Set
to 0xc0010002.
(GNU_PROPERTY_X86_ISA_1_NEEDED): Set to 0xc0008002.
* testsuite/gnu_property_test.sh: Updated.
The NT_GNU_PROPERTY_TYPE_0 note should be aligned to 8 bytes for 64-bit
ELF as specified by gABI. A note section can be only placed in a PT_NOTE
segment with the same alignment.
PR gold/22914
PR gold/23535
* layout.cc (Layout::attach_allocated_section_to_segment): Place
a note section in a PT_NOTE segment with the same alignment. Set
the alignment of the PT_NOTE segment from the alignment of the
note section.
(Layout::create_note): Align the NT_GNU_PROPERTY_TYPE_0 note to 8
bytes for 64-bit ELF.
(Layout::segment_precedes): Place segments with larger alignments
first.
* output.cc (Output_segment::Output_segment): Initialize align_.
* output.h (Output_segment): Add align, set_align and align_.
* testsuite/Makefile.am (gnu_property_test.stdout): Pass -lhSWn
to $(TEST_READELF).
(gnu_property_test): Pass --build-id to ld.
* testsuite/Makefile.in: Regenerated.
* testsuite/gnu_property_test.sh (check_alignment): New.
Use check_alignment to check the NT_GNU_PROPERTY_TYPE_0 note
alignment. Verify that there are 2 PT_NOTE segments.
With
commit 4aebb6312e
Author: Rahul Chaudhry <rahulchaudhry@google.com>
Date: Wed Feb 15 00:37:10 2017 -0800
Improved support for --icf=safe when used with -pie.
we now check opcode with R_X86_64_PC32 relocation, which tell branches
from other instructions. We can enable safe ICF for shared object on
x86-64. Also, global symbols with non-default visibility should be
folded like local symbols.
PR gold/21452
* x86_64.cc (Scan::local_reloc_may_be_function_pointer): Remove
check for shared library.
(Scan::global_reloc_may_be_function_pointer): Remove check for
shared library and symbol visibility.
* testsuite/icf_safe_so_test.cc (bar_static): New function.
(main): Take function address of bar_static and use it.
* testsuite/icf_safe_so_test.sh (arch_specific_safe_fold): Also
check fold on x86-64. Check bar_static isn't folded.
Because target_section_table only holds a vector, and because it is
used in an "open" way, this patch makes it just be an alias for the
std::vector specialization. This makes the code less wordy. If we do
ever want to add more specialized behavior to this type, it's simple
enough to convert it back to a struct with the few needed methods
implied by this change.
gdb/ChangeLog
2020-10-12 Tom Tromey <tom@tromey.com>
* target.h (struct target_ops) <get_section_table>: Update.
(target_get_section_table): Update.
* target.c (target_get_section_table, target_section_by_addr)
(memory_xfer_partial_1): Update.
* target-section.h (target_section_table): Now an alias.
* target-delegates.c: Rebuild.
* target-debug.h (target_debug_print_target_section_table_p):
Rename from target_debug_print_struct_target_section_table_p.
* symfile.c (build_section_addr_info_from_section_table): Update.
* solib.c (solib_map_sections, solib_contains_address_p): Update.
* solib-svr4.c (scan_dyntag): Update.
* solib-dsbt.c (scan_dyntag): Update.
* remote.c (remote_target::remote_xfer_live_readonly_partial):
Update.
* record-full.c (record_full_core_target::xfer_partial): Update.
* progspace.h (struct program_space) <target_sections>: Update.
* exec.h (print_section_info): Update.
* exec.c (exec_target::close, build_section_table)
(add_target_sections, add_target_sections_of_objfile)
(remove_target_sections, exec_on_vfork)
(section_table_available_memory)
(section_table_xfer_memory_partial)
(exec_target::get_section_table, exec_target::xfer_partial)
(print_section_info, set_section_command)
(exec_set_section_address, exec_target::has_memory): Update.
* corelow.c (core_target::build_file_mappings)
(core_target::xfer_partial, core_target::info_proc_mappings)
(core_target::info_proc_mappings): Update.
* bfd-target.c (class target_bfd): Update
The call to clear_section_table in ~program_space is now clearly not
needed -- the section table will clear itself. This patch removes
this call and then inlines the one remaining call to
clear_section_table.
gdb/ChangeLog
2020-10-12 Tom Tromey <tom@tromey.com>
* progspace.c (program_space::~program_space): Don't call
clear_section_table.
* exec.h (clear_section_table): Don't declare.
* exec.c (exec_target::close): Update.
(clear_section_table): Remove.
Now that target_section_table uses std::vector,
add_target_sections_of_objfile does not need to loop twice. This
patch simplifies this code to have just a single loop. Also, the
passed-in objfile can never be NULL, so this changes this function to
assert that.
gdb/ChangeLog
2020-10-12 Tom Tromey <tom@tromey.com>
* exec.c (add_target_sections_of_objfile): Simplify.
I noticed that build_section_table cannot fail. This patch changes it
to return a target_section_table and then removes the dead code.
gdb/ChangeLog
2020-10-12 Tom Tromey <tom@tromey.com>
* solib.c (solib_map_sections): Update.
* record-full.c (record_full_core_open_1): Update.
* exec.h (build_section_table): Return a target_section_table.
* exec.c (exec_file_attach): Update.
(build_section_table): Return a target_section_table.
* corelow.c (core_target::core_target): Update.
* bfd-target.c (target_bfd::target_bfd): Update.
This changes target_section_table to wrap a std::vector. This
simplifies some code, and also enables the simplifications coming in
the subsequent patches.
Note that for solib, I chose to have it use a pointer to a
target_section_table. This is more convoluted than would be ideal,
but I didn't want to convert solib to new/delete as a prerequisite for
this series.
gdb/ChangeLog
2020-10-12 Tom Tromey <tom@tromey.com>
* target.c (target_section_by_addr, memory_xfer_partial_1):
Update.
* target-section.h (struct target_section_table): Use
std::vector.
* symfile.h (build_section_addr_info_from_section_table): Take a
target_section_table.
* symfile.c (build_section_addr_info_from_section_table): Take a
target_section_table.
* solist.h (struct so_list) <sections>: Change type.
<sections_end>: Remove.
* solib.c (solib_map_sections, clear_so, solib_read_symbols)
(solib_contains_address_p): Update.
* solib-svr4.c (scan_dyntag): Update.
* solib-dsbt.c (scan_dyntag): Update.
* remote.c (remote_target::remote_xfer_live_readonly_partial):
Update.
* record-full.c (record_full_core_start, record_full_core_end):
Remove.
(record_full_core_sections): New global.
(record_full_core_open_1, record_full_core_target::xfer_partial):
Update.
* exec.h (build_section_table, section_table_xfer_memory_partial)
(add_target_sections): Take a target_section_table.
* exec.c (exec_file_attach, clear_section_table): Update.
(resize_section_table): Remove.
(build_section_table, add_target_sections): Take a
target_section_table.
(add_target_sections_of_objfile, remove_target_sections)
(exec_on_vfork): Update.
(section_table_available_memory): Take a target_section_table.
(section_table_read_available_memory): Update.
(section_table_xfer_memory_partial): Take a target_section_table.
(print_section_info, set_section_command)
(exec_set_section_address, exec_target::has_memory): Update.
* corelow.c (class core_target) <m_core_section_table,
m_core_file_mappings>: Remove braces.
<~core_target>: Remove.
(core_target::core_target): Update.
(core_target::~core_target): Remove.
(core_target::build_file_mappings)
(core_target::xfer_memory_via_mappings)
(core_target::xfer_partial, core_target::info_proc_mappings):
Update.
* bfd-target.c (target_bfd::xfer_partial): Update.
(target_bfd::target_bfd): Update.
(target_bfd::~target_bfd): Remove.
This introduces a new target-section.h file. This makes some of the
later patches in this series a bit cleaner, because new includes of
target.h won't be required. Also I think it's better to have small
header files for each separate data structure.
gdb/ChangeLog
2020-10-12 Tom Tromey <tom@tromey.com>
* target.h (struct target_section, struct target_section_table):
Move to target-section.h.
* target-section.h: New file.
Commit ccb9eba6a2 updated the testsuite for some targets without
running the testsuite on those targets. This patch corrects the
update, in most cases just adding the expected full-stop.
On powerpc64le-linux, fixes these:
FAIL: gdb.arch/powerpc-d128-regs.exp: checking for PPC arch
FAIL: gdb.arch/powerpc-disassembler-options.exp: set architecture powerpc:common64
FAIL: gdb.arch/powerpc-disassembler-options.exp: set architecture rs6000:6000
FAIL: gdb.arch/ppc64-symtab-cordic.exp: show architecture
I also verified that arm-linuxeabi and s390x-linux cross-builds now
pass their disassembler-options.exp tests.
* gdb.arch/arm-disassembler-options.exp: Adjust expected
"target architecture" output.
* gdb.arch/powerpc-d128-regs.exp: Likewise.
* gdb.arch/powerpc-disassembler-options.exp: Likewise.
* gdb.arch/ppc64-symtab-cordic.exp: Likewise.
* gdb.arch/s390-disassembler-options.exp: Likewise.
The gdb.cp/ambiguous.exp testcase had been disabled for many years,
but recently it was re-enabled. However, it is failing everywhere.
That is because it is testing an old feature that is gone from GDB.
The testcase is expecting to see an ambiguous field warning, like:
# X is derived from A1 and A2; both A1 and A2 have a member 'x'
send_gdb "print x.x\n"
gdb_expect {
-re "warning: x ambiguous; using X::A2::x. Use a cast to disambiguate.\r\n\\$\[0-9\]* = \[-\]*\[0-9\]*\r\n$gdb_prompt $" {
pass "print x.x"
}
-re "warning: x ambiguous; using X::A1::x. Use a cast to disambiguate.\r\n\\$\[0-9\]* = \[-\]*\[0-9\]*\r\n$gdb_prompt $" {
pass "print x.x"
}
-re ".*$gdb_prompt $" { fail "print x.x" }
timeout { fail "(timeout) print x.x" }
}
However, GDB just accesses one of the candidates without warning or
error:
print x.x
$1 = 1431655296
(gdb) FAIL: gdb.cp/ambiguous.exp: print x.x
(The weird number is because the testcase does not initialize the
variables.)
The testcase come in originally with the big HP merge:
+Sun Jan 10 23:44:11 1999 David Taylor <taylor@texas.cygnus.com>
+
+
+ The following files are part of the HP merge; some had longer
+ names at HP, but have been renamed to be no more than 14
+ characters in length.
Looking at the tree back then, we find that warning:
/* Helper function used by value_struct_elt to recurse through baseclasses.
Look for a field NAME in ARG1. Adjust the address of ARG1 by OFFSET bytes,
and search in it assuming it has (class) type TYPE.
If found, return value, else return NULL.
If LOOKING_FOR_BASECLASS, then instead of looking for struct fields,
look for a baseclass named NAME. */
static value_ptr
search_struct_field (name, arg1, offset, type, looking_for_baseclass)
char *name;
register value_ptr arg1;
int offset;
register struct type *type;
int looking_for_baseclass;
{
int found = 0;
char found_class[1024];
value_ptr v;
struct type *vbase = NULL;
found_class[0] = '\000';
v = search_struct_field_aux (name, arg1, offset, type, looking_for_baseclass, &found, found_class, &vbase);
if (found > 1)
warning ("%s ambiguous; using %s::%s. Use a cast to disambiguate.",
name, found_class, name);
return v;
}
However, in current GDB, search_struct_field does not handle the
ambiguous field case, nor is that warning found anywhere. Somehow it
got lost over the years. That seems like a regression, because the
compiler (as per language rules) rejects the ambiguous accesses as
well. E.g.:
gdb.cp/ambiguous.cc:98:5: error: request for member 'x' is ambiguous
98 | x.x = 1;
| ^
gdb.cp/ambiguous.cc:10:7: note: candidates are: 'int A2::x'
10 | int x;
| ^
gdb.cp/ambiguous.cc:4:7: note: 'int A1::x'
4 | int x;
| ^
This patch restores the feature, though implemented differently and
with better user experience, IMHO. An ambiguous access is now an
error instead of a warning, and also GDB shows you all the candidates,
like:
(gdb) print x.x
Request for member 'x' is ambiguous in type 'X'. Candidates are:
'int A1::x' (X -> A1)
'int A2::x' (X -> A2)
(gdb) print j.x
Request for member 'x' is ambiguous in type 'J'. Candidates are:
'int A1::x' (J -> K -> A1)
'int A1::x' (J -> L -> A1)
Users can then fix their commands by casting or by specifying the
baseclass explicitly, like:
(gdb) p x.A1::x
$1 = 1
(gdb) p x.A2::x
$2 = 2
(gdb) p ((A1) x).x
$3 = 1
(gdb) p ((A2) x).x
$4 = 2
(gdb) p j.K::x
$12 = 1
(gdb) p j.L::x
$13 = 2
(gdb) p j.A1::x
base class 'A1' is ambiguous in type 'J'
The last error I've not touched; could be improved to also list the
baseclass candidates.
The showing the class "path" for each candidate was inspired by GCC's
output when you try an ambiguous cast:
gdb.cp/ambiguous.cc:161:8: error: ambiguous conversion from derived class 'const JVA1' to base class 'const A1':
class JVA1 -> class KV -> class A1
class JVA1 -> class A1
(A1) jva1;
^~~~
I did not include the "class" word as it seemed unnecessarily
repetitive, but I can include it if people prefer it:
(gdb) print j.x
Request for member 'x' is ambiguous in type 'J'. Candidates are:
'int A1::x' (class J -> class K -> class A1)
'int A1::x' (class J -> class L -> class A1)
The testcase is adjusted accordingly. I also took the chance to
modernize it at the same time.
Also, as mentioned above, the testcase doesn't currently initialize
the tested variables. This patch inializes them all, giving each
field a distinct value, so that we can be sure that GDB is accessing
the right fields / offsets. The testcase is extended accordingly.
Unfortunately, this exposes a bug, not addressed in this patch. The
bug is around a class that inherits from A1 directly and also inherits
from two other distinct base classes that inherit virtually from A1 in
turn:
print jva1.KV::x
$51 = 1431665544
(gdb) FAIL: gdb.cp/ambiguous.exp: all fields: print jva1.KV::x
print jva1.KV::y
$52 = 21845
(gdb) FAIL: gdb.cp/ambiguous.exp: all fields: print jva1.KV::y
(gdb) print /x (KV)jva1
$4 = {<A1> = <invalid address>, _vptr.KV = 0x555555557b88 <vtable for JVA1+24>, i = 0x457}
(gdb) print /x (A1)(KV)jva1
Cannot access memory at address 0x0
Since that's an orthogonal issue, I filed PR c++/26550 and kfailed the
tests that fail because of it.
gdb/ChangeLog:
PR exp/26602
* valops.c (struct struct_field_searcher): New.
(update_search_result): Rename to ...
(struct_field_searcher::update_result): ... this. Simplify
prototype. Record all found fields.
(do_search_struct_field): Rename to ...
(struct_field_searcher::search): ... this. Simplify prototype.
Maintain stack of visited baseclass path. Call update_result for
fields too. Keep searching fields in baseclasses instead of
stopping at the first found field.
(search_struct_field): Use struct_field_searcher. When looking
for fields, report ambiguous access attempts.
gdb/testsuite/ChangeLog:
PR exp/26602
PR c++/26550
* gdb.cp/ambiguous.cc (marker1): Delete.
(main): Initialize all the fields of the locals. Replace marker1
call with a "set breakpoint here" marker.
* gdb.cp/ambiguous.exp: Modernize. Use gdb_continue_to_breakpoint
instead of running to marker1. Add tests printing all the
variables and all the fields of the variables.
(test_ambiguous): New proc, expecting the new GDB output when a
field access is ambiguous. Change all "warning: X ambiguous"
tests to use it.
A number of testcases define variables and/or functions which are
referenced by GDB during the test, but which are not referenced from
within the test executable. Clang correctly recognizes that these
variables and functions are unused, and optimizes them out, causing
the testcases in question to fail. This commit adds __attribute__
((used)) in various places to prevent this.
gdb/testsuite/ChangeLog:
* gdb.base/msym-bp.c (foo): Add __attribute__ ((used)).
* gdb.base/msym-bp-2.c (foo): Likewise.
* gdb.base/msym-lang.c (foo): Likewise.
* gdb.base/msym-lang-main.c (foo): Likewise.
* gdb.base/symtab-search-order-1.c (static_global): Likewise.
* gdb.guile/scm-pretty-print.c (eval_func): Likewise.
* gdb.mi/mi-sym-info-1.c (global_f1): Likewise.
* gdb.mi/mi-sym-info-2.c (global_f1, var1, var2): Likewise.
* gdb.multi/watchpoint-multi-exit.c (globalvar): Likewise.
* gdb.python/py-as-string.c (enum_valid, enum_invalid): Likewise.
* gdb.python/py-objfile.c (static_var): Likewise.
* gdb.python/py-symbol.c (rr): Likewise.
* gdb.python/py-symbol-2.c (anon, rr): Likewise.
* gdb.mi/mi-sym-info.exp (lineno1, lineno2): Updated.
Currently, GDB will only stop the backtrace at the main function if
there is a minimal symbol with the matching name. In Fortran programs
compiled with gfortran this is not the case. The main function is
present in the DWARF, and as marked as DW_AT_main_subprogram, but
there's no minimal symbol.
This commit extends `inside_main_func` to check the full symbols if no
matching minimal symbol is found.
There's an updated test case that covers this change.
gdb/ChangeLog:
* frame.c (inside_main_func): Check full symbols as well as
minimal symbols.
gdb/testsuite/ChangeLog:
* gdb.fortran/mixed-lang-stack.exp (run_tests): Update expected
output of backtrace.
