This patch handles another aspect of the ELFv2 ABI, which unfortunately
requires common code changes.
In ELFv2, functions may provide both a global and a local entry point.
The global entry point (where the function symbol points to) is intended
to be used for function-pointer or cross-module (PLT) calls, and requires
r12 to be set up to the entry point address itself. The local entry
point (which is found at a fixed offset after the global entry point,
as defined by bits in the symbol table entries' st_other field), instead
expects r2 to be set up to the current TOC.
Now, when setting a breakpoint on a function by name, you really want
that breakpoint to trigger either way, no matter whether the function
is called via its local or global entry point. Since the global entry
point will always fall through into the local entry point, the way to
achieve that is to simply set the breakpoint at the local entry point.
One way to do that would be to have prologue parsing skip the code
sequence that makes up the global entry point. Unfortunately, this
does not work reliably, since -for optimized code- GDB these days
will not actuall invoke the prologue parsing code but instead just
set the breakpoint at the symbol address and rely on DWARF being
correct at any point throughout the function ...
Unfortunately, I don't really see any way to express the notion of
local entry points with the current set of gdbarch callbacks.
Thus this patch adds a new callback, skip_entrypoint, that is
somewhat analogous to skip_prologue, but is called every time
GDB needs to determine a function start address, even in those
cases where GDB decides to not call skip_prologue.
As a side effect, the skip_entrypoint implementation on ppc64
does not need to perform any instruction parsing; it can simply
rely on the local entry point flags in the symbol table entry.
With this implemented, two test cases would still fail to set
the breakpoint correctly, but that's because they use the construct:
gdb_test "break *hello"
Now, using "*hello" explicitly instructs GDB to set the breakpoint
at the numerical value of "hello" treated as function pointer, so
it will by definition only hit the global entry point.
I think this behaviour is unavoidable, but acceptable -- most people
do not use this construct, and if they do, they get what they
asked for ...
In one of those two test cases, use of this construct is really
not appropriate. I think this was added way back when as a means
to work around prologue skipping problems on some platforms. These
days that shouldn't really be necessary any more ...
For the other (step-bt), we really want to make sure backtracing
works on the very first instruction of the routine. To enable that
test also on powerpc64le-linux, we can modify the code to call the
test function via function pointer (which makes it use the global
entry point in the ELFv2 ABI).
gdb/ChangeLog:
* gdbarch.sh (skip_entrypoint): New callback.
* gdbarch.c, gdbarch.h: Regenerate.
* symtab.c (skip_prologue_sal): Call gdbarch_skip_entrypoint.
* infrun.c (fill_in_stop_func): Likewise.
* ppc-linux-tdep.c: Include "elf/ppc64.h".
(ppc_elfv2_elf_make_msymbol_special): New function.
(ppc_elfv2_skip_entrypoint): Likewise.
(ppc_linux_init_abi): Install them for ELFv2.
gdb/testsuite/ChangeLog:
* gdb.base/sigbpt.exp: Do not use "*" when setting breakpoint
on a function.
* gdb.base/step-bt.c: Call hello via function pointer to make
sure its first instruction is executed on powerpc64le-linux.
* syscalls/s390x-linux.xml: New file.
* syscalls/s390-linux.xml: New file.
* s390-linux-tdep.c (XML_SYSCALL_FILENAME_S390): New macro.
(XML_SYSCALL_FILENAME_S390X): Likewise.
(op_svc): New enum value for SVC opcode.
(s390_sigtramp_frame_sniffer): Replace literal by 'op_svc'.
(s390_linux_get_syscall_number): New function.
(s390_gdbarch_init): Register '*get_syscall_number' and the
syscall xml file name.
* data-directory/Makefile.in (SYSCALLS_FILES): Add
"s390-linux.xml" and "s390x-linux.xml".
* NEWS: Announce new feature.
gdb/testsuite/ChangeLog:
* gdb.base/catch-syscall.exp: Activate test on s390*-linux.
When upstream gcc is given a command line with the "-g" option after
"-g3", it doesn't generate a ".debug_macro" section. This is because
the last option wins, thus downgrading the debug level again. Without
any macro debug information in the executable, info-macros.exp
obviously produces many failures.
Since the "-g" option is appended by DejaGnu's target_compile whenever
the "debug" option is set, the fix just removes that option.
gdb/testsuite/ChangeLog:
* gdb.base/info-macros.exp: Remove "debug" from the compile
options.
gdb/ChangeLog:
2014-01-07 Edjunior Barbosa Machado <emachado@linux.vnet.ibm.com>
* source.c (add_path): Fix check for duplicated paths in the previously
included paths.
gdb/testsuite/ChangeLog:
2014-01-07 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.base/source-dir.exp: New file.
Code rationale
==============
by: Gabriel Krisman Bertazi
This is a fix for bug 16297. The problem occurs when the user attempts
to catch any syscall 0 (such as syscall read on Linux/x86_64). GDB was
not able to catch the syscall and was missing the breakpoint.
Now, breakpoint_hit_catch_syscall returns immediately when it finds the
correct syscall number, avoiding a following check for the end of the
search vector, that returns a no hit if the syscall number was zero.
Testcase rationale
==================
by: Sergio Durigan Junior
This testcase is a little difficult to write. By doing a quick
inspection at the Linux source, one can see that, in many targets, the
syscall number 0 is restart_syscall, which is forbidden to be called
from userspace. Therefore, on many targets, there's just no way to test
this safely.
My decision was to take the simpler route and just adds the "read"
syscall on the default test. Its number on x86_64 is zero, which is
"good enough" since many people here do their tests on x86_64 anyway and
it is a popular architecture.
However, there was another little gotcha. When using "read" passing 0
as the third parameter (i.e., asking it to read 0 bytes), current libc
implementations could choose not to effectively call the syscall.
Therefore, the best solution was to create a temporary pipe, write 1
byte into it, and then read this byte from it.
gdb/ChangeLog
2013-12-19 Gabriel Krisman Bertazi <gabriel@krisman.be>
PR breakpoints/16297
* breakpoint.c (breakpoint_hit_catch_syscall): Return immediately
when expected syscall is hit.
gdb/testsuite/ChangeLog
2013-12-19 Sergio Durigan Junior <sergiodj@redhat.com>
PR breakpoints/16297
* gdb.base/catch-syscall.c (read_syscall, pipe_syscall)
(write_syscall): New variables.
(main): Create a pipe, write 1 byte in it, and read 1 byte from
it.
* gdb.base/catch-syscall.exp (all_syscalls): Include "pipe,
"write" and "read" syscalls.
(fill_all_syscalls_numbers): Improve the way to obtain syscalls
numbers.
While fixing another bug, I found that the current
gdb.base/catch-syscall.exp is kind of messy, could use some
improvements, and is not correctly testing some things.
I've made the following patch to address all the issues I found. On the
organization side, it does a cleanup and removes unecessary imports of
gdb_prompt, uses prepare_for_testing and clean_restart where needed, and
fixes some comments. The testcase was also not correctly testing
catching syscalls using only numbers, or catching many syscalls at
once. I fixed that.
The patch also uses a new method for obtaining the syscalls numbers: it
relies on the C source file to get them, via <sys/syscall.h> and SYS_*
macros. This makes the .exp file simpler because there is no need to
include target conditionals there.
I tested this on x86_64 Fedora 18.
gdb/testsuite/ChangeLog:
2013-12-18 Sergio Durigan Junior <sergiodj@redhat.com>
* gdb.base/catch-syscall.c: Include <sys/syscall.h>.
(close_syscall, chroot_syscall, exit_group_syscall): New
variables.
* gdb.base/catch-syscall.exp: Replace gdb_compile by
prepare_for_testing. Call fill_all_syscalls_numbers before
starting. Replace gdb_exit, gdb_start, gdb_reinitialize_dir and
gdb_load by clean_restart.
(check_info_bp_any_syscall, check_info_bp_specific_syscall)
(check_info_bp_many_syscalls): Remove global gdb_prompt.
(check_call_to_syscall): Likewise. Add global decimal. Improve
testing regex.
(check_return_from_syscall): Likewise.
(check_continue, insert_catch_syscall_with_arg): Remove global
gdb_prompt.
(insert_catch_syscall_with_many_args): Likewise. Add global
decimal. Fix $filter_str. Improve testing regex.
(check_for_program_end): Remove global gdb_prompt.
(test_catch_syscall_without_args): Likewise. Add global decimal.
Improve testing regex.
(test_catch_syscall_with_args, test_catch_syscall_with_many_args)
(test_catch_syscall_with_wrong_args)
(test_catch_syscall_restarting_inferior)
(test_catch_syscall_fail_nodatadir): Remove global gdb_prompt.
(do_syscall_tests): Likewise. Remove global srcdir.
(test_catch_syscall_without_args_noxml): Remove global gdb_prompt.
Add global last_syscall_number. Test for the exact syscall number
to be caught.
(test_catch_syscall_with_args_noxml): Remove global gdb_prompt.
Add global all_syscalls_numbers. Test each syscall number to be
caught, instead of only testing "close".
(test_catch_syscall_with_wrong_args_noxml): Remove global gdb_prompt.
(do_syscall_tests_without_xml): Likewise. Remove global srcdir.
Remove stale comment.
(fill_all_syscalls_numbers): Add global last_syscall_number. Fill
the correct syscall numbers using information from the inferior.
These files are source files and have no business being +x. We couldn't
easily fix it in CVS (you need login+write access to the raw rcs files),
but we can fix this w/git.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2013-10-03 Jose E. Marchesi <jose.marchesi@oracle.com>
* gdb.base/sigall.exp (test_one_sig): gdb identifies SIGLOST as a
SIGPWR in sparc64.
* gdb.base/sigall.c (main): In some targets SIGLOST and SIGPWR
have the same signal number. Handle this situation.
I was "lucky" enough that an unrelated patch changed how many symtabs
GDB expands in a plain run to main, and that triggered a latent issue
in this test:
PASS: gdb.base/maint.exp: maint print objfiles: header
PASS: gdb.base/maint.exp: maint print objfiles: psymtabs
FAIL: gdb.base/maint.exp: maint print objfiles: symtabs
The problem is in my case, expect is managing to alway put in the
buffer chunks like this:
Psymtabs:
../../../src/gdb/testsuite/gdb.base/break1.c at 0x1ed2280, ../../../src/gdb/testsuite/gdb.base/break.c at 0x1ed21d0,
Symtabs:
../../../src/gdb/testsuite/gdb.base/break.c at 0x1f044f0, /usr/include/stdio.h at 0x1ed25a0, /usr/include/libio.h at 0x1ed2510, /usr/include/bits/types.h at 0x1ed2480, /usr/lib/gcc/x86_64-redhat-linux/4.7.2/include/stddef.h at 0x1ed23f0,
Object file /usr/lib/debug/lib64/ld-2.15.so.debug: Objfile at 0x1f4bff0, bfd at 0x1f2d940, 0 minsyms
Psymtabs:
bsearch.c at 0x1f65340, ../sysdeps/x86_64/multiarch/init-arch.c at
0x1f65290, ...
Note: Psymtabs:/Symtabs:/Psymtabs:.
So, the loop matches the first Psymtabs in the buffer. Then we're
left with
../../../src/gdb/testsuite/gdb.base/break1.c at 0x1ed2280, ../../../src/gdb/testsuite/gdb.base/break.c at 0x1ed21d0,
Symtabs:
../../../src/gdb/testsuite/gdb.base/break.c at 0x1f044f0, /usr/include/stdio.h at 0x1ed25a0, /usr/include/libio.h at 0x1ed2510, /usr/include/bits/types.h at 0x1ed2480, /usr/lib/gcc/x86_64-redhat-linux/4.7.2/include/stddef.h at 0x1ed23f0,
Object file /usr/lib/debug/lib64/ld-2.15.so.debug: Objfile at 0x1f4bff0, bfd at 0x1f2d940, 0 minsyms
Psymtabs:
bsearch.c at 0x1f65340, ../sysdeps/x86_64/multiarch/init-arch.c at
0x1f65290, ...
In the next iteration, because the psymtabs regex comes first, we
match with the Psymtabs: line, then of course, end up with just
bsearch.c at 0x1f65340, ../sysdeps/x86_64/multiarch/init-arch.c at
0x1f65290, ...
in the buffer. The "Symtabs:" line is lost. expect then reads more
gdb output, and manages to again retrieve the same pattern. Rinse,
repeat, and the test never matches any "Symtab:" line.
We don't know the order the matches lines will appear, so the fix is
to consume one line at a time, and run it through all three milestone
regexes.
gdb/testsuite/
2013-11-20 Pedro Alves <palves@redhat.com>
* gdb.base/maint.exp (maint print objfiles): Consume one line at a
time, and run it through all three milestone regexes.
Ensure that certain commands (e.g. whatis/ptype) and sizeof intrinsic
have no side effects (variables cannot be altered).
2013-11-20 Sanimir Agovic <sanimir.agovic@intel.com>
testsuite/
* gdb.base/eval-avoid-side-effects.exp: New test.
A few tests run an inferior that execs some other program. The name
of this exec'd program is compiled in. These tests assume the current
test suite directory layout, but fail in parallel mode.
This patch fixes these tests by letting the .exp files pass in the
directory names at compile time.
2013-11-04 Tom Tromey <tromey@redhat.com>
* gdb.base/foll-exec.c (main): Use BASEDIR.
* gdb.base/foll-exec.exp: Define BASEDIR during compilation.
* gdb.base/foll-vfork.c (main): Use BASEDIR.
* gdb.base/foll-vfork.exp: Define BASEDIR during compilation.
* gdb.multi/bkpt-multi-exec.c (main): Use BASEDIR.
* gdb.multi/bkpt-multi-exec.exp: Define BASEDIR during compilation.
argv0-symlink.exp doesn't work properly if standard_output_file puts
files into a per-test subdirectory. That's because it assumes that
files appear in $subdir, which is no longer true.
This patch fixes the problem by computing the correct directory at
runtime.
Tested both with and without GDB_PARALLEL on x86-64 Fedora 18.
2013-11-04 Tom Tromey <tromey@redhat.com>
* gdb.base/argv0-symlink.exp: Compute executable's directory
dynamically.
This introduces a new relative_filename proc to gdb.exp and changes
some tests to use it. This helps make these tests parallel-safe.
2013-11-04 Tom Tromey <tromey@redhat.com>
* gdb.base/fullname.exp: Use standard_output_file,
relative_filename.
* gdb.base/hashline1.exp: Use standard_testfile,
standard_output_file, relative_filename, clean_restart.
* gdb.base/hashline2.exp: Use standard_testfile,
standard_output_file.
* gdb.base/hashline3.exp: Use standard_testfile,
standard_output_file, relative_filename.
* lib/gdb.exp (relative_filename): New proc.
This updates the fileio test to be parallel-safe.
2013-11-04 Tom Tromey <tromey@redhat.com>
* gdb.base/fileio.c (test_open, test_write, test_read)
(test_lseek, test_close, test_stat, test_fstat)
(test_isatty, test_system, test_rename, test_unlink):
Use OUTDIR define.
* gdb.base/fileio.exp: Define OUTDIR during compilation.
Use standard_output_file.
This fixes the "checkpoint" test to use the standard output directory.
This makes the test be parallel-safe.
2013-11-04 Tom Tromey <tromey@redhat.com>
* gdb.base/checkpoint.c (main): Use PI_TXT and COPY1_TXT
defines.
* gdb.base/checkpoint.exp: Define PI_TXT and COPY1_TXT during
compilation. Use prepare_for_testing, standard_output_file.
This makes more changes in gdb.base to make it parallel-safe. I think
the changes in this particular patch are relatively straightforward,
so I've grouped them all together.
2013-11-04 Tom Tromey <tromey@redhat.com>
* gdb.base/advance.exp: Use standard_testfile and
prepare_for_testing.
* gdb.base/bigcore.exp: Use standard_output_file. "cd" to
appropriate directory when local.
* gdb.base/dump.exp: Use standard_output_file. Update all
"dump" and "restore" filenames.
* gdb.base/interact.exp: Use standard_output_file.
* gdb.base/jit-so.exp: Don't download file when local.
* gdb.base/jit.exp (compile_jit_test): Don't download file
when local.
* gdb.base/list.exp: Use gdb_remote_download.
* gdb.base/maint.exp: Use standard_output_file.
* gdb.base/prelink.exp: Use standard_output_file.
* gdb.base/save-bp.exp: Use standard_output_file.
* gdb.base/sepdebug.exp: Use standard_testfile,
standard_output_file.
(test_different_dir): Don't declare objdir.
* gdb.base/solib-search.exp: Use standard_output_file.
* gdb.base/step-line.exp: Use gdb_remote_download.
* gdb.base/trace-commands.exp: Use standard_output_file.
This fixes some parallelization thinkos from a while ago. I'm not
sure how the problems ever slipped through. In addition to a thinko
fix in twice.exp, this also finishes fixing it up for parallelization.
2013-11-04 Tom Tromey <tromey@redhat.com>
* gdb.base/gcore-buffer-overflow.exp: Use
standard_output_file, not standard_testfile.
* gdb.base/twice.exp: Use standard_testfile, not
standard_output_file. Use gdb_remote_download.
This test exercises the commands 'add-symbol-file'
and 'remove-symbol-file'.
2013-10-29 Nicolas Blanc <nicolas.blanc@intel.com>
gdb/testsuite
* gdb.base/sym-file-lib.c: New file.
* gdb.base/sym-file-loader.c: New file.
* gdb.base/sym-file-loader.h: New file.
* gdb.base/sym-file-main.c: New file.
* gdb.base/sym-file.exp: New file.
Signed-off-by: Nicolas Blanc <nicolas.blanc@intel.com>
Some remote stubs do not have a proper exit() function implementation.
gdb.base/bang.exp was failing on those targets due to timeout. With
this patch bang.exp uses already defined library procedures to handle
this situation gracefully without breaking native targets.
Tested with x86_64 (unix, native-gdbserver) and with arc-*-elf32.
gdb/testsuite/ChangeLog:
2013-10-25 Anton Kolesov <Anton.Kolesov@synopsys.com> (tiny change)
* gdb.base/bang.exp: Use gdb_continue_to_end to properly support
remote stubs where exit() behaviour is unreliable.
PR gdb/15986
* gdb.base/run.c (main): gdb_get_line_number tag added for
commands.exp.
(factorial): Likewise.
* gdb.base/commands.exp (watchpoint_command_test): Use
gdb_get_line_number in order to determine the locations in run.c
where local_var is detected to go out of scope.
https://sourceware.org/ml/gdb-patches/2013-10/msg00477.html
gdb/ChangeLog
* breakpoint.c (update_watchpoint): If hardware watchpoints are
forced off, downgrade them to software watchpoints if possible,
and error out if not possible.
(watch_command_1): Move watchpoint type selection closer to
watchpoint creation, and extend the comments.
gdb/testsuite/ChangeLog
* gdb.base/watchpoints.exp: Add test for setting software
watchpoints of different types before starting the inferior.
This patch fixes PR gdb/15995.
The bug here is that gdb's printf command does not flush the output
stream. This makes a printf that is not newline-terminated interleave
incorrectly with other forms of output, such as that generated via a
call to an external program using "shell".
I note that the "output" command already does this flushing.
The fix is to call gdb_flush in printf_command.
Built and regtested on x86-64 Fedora 18.
New test case included.
PR gdb/15995:
* printcmd.c (printcmd): Call gdb_flush.
* gdb.base/printcmds.exp (test_printf): Test printf flushing.
gdb/
2013-10-13 Jan Kratochvil <jan.kratochvil@redhat.com>
Canonicalize directories for EXEC_FILENAME.
* exec.c (exec_file_attach): Use gdb_realpath_keepfile for
exec_filename.
* utils.c (gdb_realpath_keepfile): New function.
* utils.h (gdb_realpath_keepfile): New declaration.
gdb/testsuite/
2013-10-13 Jan Kratochvil <jan.kratochvil@redhat.com>
Canonicalize directories for EXEC_FILENAME.
* gdb.base/argv0-symlink.exp
(kept file symbolic link name for info inferiors): New.
(kept directory symbolic link name): Setup kfail.
(kept directory symbolic link name for info inferiors): New.
Consider the following example:
% gdb -q -batch -ex 'source nonexistant-file'
[nothing]
One would have at least expected the debugger to warn about
not finding the file, similar to the error shown when using
a more interactive mode. Eg:
(gdb) source nonexistant-file
nonexistant-file: No such file or directory.
Not raising an error appears to be intentional, presumably in order
to prevent this situation from stoping the execution of a GDB script.
But the lack of at least a warning makes it harder for a user to
diagnose any issue, if the file was expected to be there and readable.
This patch adds a warning in that case:
% gdb -q -batch -ex 'source nonexistant-file'
warning: nonexistant-file: No such file or directory.
gdb/ChangeLog:
* utils.h (perror_warning_with_name): Add declaration.
* utils.c (perror_warning_with_name): New function.
* cli/cli-cmds.c (source_script_with_search): Add call to
perror_warning_with_name if from_tty is nul.
gdb/testsuite/ChangeLog:
* gdb.base/source-nofile.gdb: New file.
* gdb.base/source.exp: Add two tests verifying the behavior when
the "source" command is given a non-existant filename.
catch-syscall.exp has a series of duplicated output in gdb.sum. This
patch makes sure all test names are unique, using with_test_prefix.
Tested on x86_64 Fedora 17.
gdb/testsuite/
2013-10-09 Pedro Alves <palves@redhat.com>
* gdb.base/catch-syscall.exp (test_catch_syscall_without_args)
(test_catch_syscall_with_args, test_catch_syscall_with_many_args)
(test_catch_syscall_with_wrong_args)
(test_catch_syscall_restarting_inferior)
(test_catch_syscall_fail_nodatadir)
(test_catch_syscall_without_args_noxml)
(test_catch_syscall_with_args_noxml)
(test_catch_syscall_with_wrong_args_noxml): Use with_test_prefix.
will hold the signal number when the inferior terminates due to the
uncaught signal.
I've made modifications on infrun.c:handle_inferior_event such that
$_exitcode gets cleared when the inferior signalled, and vice-versa.
This assumption was made because the variables are mutually
exclusive, i.e., when the inferior terminates because of an uncaught
signal it is not possible for it to return. I have also made modifications
such that when a corefile is loaded, $_exitsignal gets set to the uncaught
signal that "killed" the inferior, and $_exitcode is cleared.
The patch also adds a NEWS entry, documentation bits, and a testcase. The
documentation entry explains how to use $_exitsignal and $_exitcode in a
GDB script, by making use of the new $_isvoid convenience function.
gdb/
2013-10-06 Sergio Durigan Junior <sergiodj@redhat.com>
* NEWS: Mention new convenience variable $_exitsignal.
* corelow.c (core_open): Reset exit convenience variables. Set
$_exitsignal to the uncaught signal which generated the corefile.
* infrun.c (handle_inferior_event): Reset exit convenience
variables. Set $_exitsignal for TARGET_WAITKIND_SIGNALLED.
(clear_exit_convenience_vars): New function.
* inferior.h (clear_exit_convenience_vars): New prototype.
gdb/testsuite/
2013-10-06 Sergio Durigan Junior <sergiodj@redhat.com>
* gdb.base/corefile.exp: Test whether $_exitsignal is set and
$_exitcode is void when opening a corefile.
* gdb.base/exitsignal.exp: New file.
* gdb.base/segv.c: Likewise.
* gdb.base/normal.c: Likewise.
gdb/doc/
2013-10-06 Sergio Durigan Junior <sergiodj@redhat.com>
* gdb.texinfo (Convenience Variables): Document $_exitsignal.
Update entry for $_exitcode.
2013-09-25 Andreas Arnez <arnez@linux.vnet.ibm.com>
PR shlibs/8882
* solib-svr4.c (svr4_read_so_list): Skip the vDSO when reading
link map entries.
testsuite/ChangeLog:
2013-09-25 Andreas Arnez <arnez@linux.vnet.ibm.com>
PR shlibs/8882
* gdb.base/corefile.exp: Add a check to assure warning-free
core-file load.
function. It adds a check for $_isvoid during the test of "show convenience"
output.
gdb/testsuite/
2013-09-17 Sergio Durigan Junior <sergiodj@redhat.com>
* gdb.base/defaults.exp (<show_conv_list>): Add check for $_isvoid
convenience function.
* gdb.base/catch-load.c: Remove the include of "dlfcn.h".
[__WIN32__]: Include "windows.h" and define macro dlopen
and dlclose.
[!__WIN32__]: Include "dlfcn.h".
* gdb.base/catch-load.exp (one_catch_load_test): Match
directory separator.
<https://sourceware.org/ml/gdb-patches/2013-09/msg00301.html>
<https://sourceware.org/ml/gdb-patches/2013-09/msg00383.html>
This patch adds a new convenience function called $_isvoid, whose
only purpose is to check whether an expression is void or not.
This became necessary because the new convenience variable
$_exitsignal (not yet approved) has a mutual exclusive behavior
with $_exitcode, i.e., when one is "defined" (i.e., non-void),
the other is cleared (i.e., becomes void). Doug wanted a way to
identify which variable to use, and checking for voidness is the
obvious solution.
It is worth mentioning that my first attempt, after a conversation with
Doug, was to actually implement a new $_isdefined() convenience
function. I would do that (for convenience variables) by calling
lookup_only_internalvar. However, I found a few problems:
- Whenever I called $_isdefined ($variable), $variable became defined
(with a void value), and $_isdefined always returned true.
- Then, I tried to implement $_isdefined ("variable"), and do the "$" +
"variable" inside GDB, thus making it impossible for GDB to create the
convenience variable. However, it was hard to extract the string
without having to mess with values and their idiossincrasies.
Therefore, I decided to abandon this attempt (specially because I
didn't want to spend too much time struggling with it).
Anyway, after talking to Doug again we decided that it would be easier
to implement $_isvoid, and this will probably help in cases like
<http://stackoverflow.com/questions/3744554/testing-if-a-gdb-convenience-variable-is-defined>.
I wrote a NEWS entry for it, and some new lines on the documentation.
gdb/
2013-09-16 Sergio Durigan Junior <sergiodj@redhat.com>
* NEWS: Mention new convenience function $_isvoid.
* value.c (isvoid_internal_fn): New function.
(_initialize_values): Add new convenience function $_isvoid.
gdb/doc/
2013-09-16 Sergio Durigan Junior <sergiodj@redhat.com>
* gdb.texinfo (Convenience Functions): Mention new convenience
function $_isvoid.
gdb/testsuite/
2013-09-16 Sergio Durigan Junior <sergiodj@redhat.com>
* gdb.base/gdbvars.c (foo_void): New function.
(foo_int): Likewise.
* gdb.base/gdbvars.exp (test_convenience_functions): New
function. Call it.
gdb/doc/
2013-09-11 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.texinfo (MiniDebugInfo): Prepare file debug and use it to create
mini_debuginfo. Strip binary before adding mini_debuginfo to it.
gdb/testsuite/
2013-09-11 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.base/gnu-debugdata.exp (objcopy 1): Move it lower and use only
debug part of the binary.
Doug Evans
Ulrich Weigand
Edjunior Barbosa Machado
Andreas Arnez
Andreas Arnez
Maciej W. Rozycki
Hui Zhu
Joel Brobecker
Gabriel Krisman Bertazi
Sergio Durigan Junior
Mike Frysinger
Doug Evans
Jose E. Marchesi
Luis Machado
Andrew Burgess
Pedro Alves
Sanimir Agovic
Tom Tromey
Nicolas Blanc
Anton Kolesov
Jan Kratochvil
Joel Brobecker
Yao Qi
Ulrich Weigand