This changes value_enclosing_type to be a method of value. Much of
this patch was written by script.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
This changes deprecated_set_value_type to be a method of value. Much
of this patch was written by script.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
This moves struct value to value.h. For now, all members remain
public, but this is a temporary state -- by the end of the series
we'll add 'private'.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
struct value is going to move to value.h, but to avoid having
excessive code there, first move the destructor body out-of-line.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
This commit finishes the task that was started in the previous
commit.
Now that all Python TUI window factories are correctly deleted when
the Python interpreter is shut down, we no longer need to dynamically
allocate the known_window_types map in tui-layout.c
This commit changes known_window_types to a statically allocated data
structure, removes the dynamic allocation from
initialize_known_windows, and then replaces lots of '->' with '.'
throughout this file.
There should be no user visible changes after this commit.
Reviewed-By: Tom Tromey <tom@tromey.com>
The previous commit relied on spotting when a Python defined TUI
window factory was deleted. I spotted that the window factories are
not deleted when GDB shuts down its Python environment, they are only
deleted when one window factory replaces another. Consider this
example Python script:
class TestWindowFactory:
def __init__(self, msg):
self.msg = msg
print("Entering TestWindowFactory.__init__: %s" % self.msg)
def __call__(self, tui_win):
print("Entering TestWindowFactory.__call__: %s" % self.msg)
return TestWindow(tui_win, self.msg)
def __del__(self):
print("Entering TestWindowFactory.__del__: %s" % self.msg)
gdb.register_window_type("test_window", TestWindowFactory("A"))
gdb.register_window_type("test_window", TestWindowFactory("B"))
And this GDB session:
(gdb) source tui.py
Entering TestWindowFactory.__init__: A
Entering TestWindowFactory.__init__: B
Entering TestWindowFactory.__del__: B
(gdb) quit
Notice that when the 'B' window replaces the 'A' window we see the 'A'
object being deleted. But, when Python is shut down (after the
'quit') the 'B' object is never deleted.
Instead, GDB retains a reference to the window factory object, which
forces the Python object to remain live even after the Python
interpreter itself has been shut down.
The references themselves are held in a dynamically allocated
std::unordered_map (in tui/tui-layout.c) which is never deallocated,
thus the underlying Python references are never decremented to zero,
and so GDB never tries to delete these Python objects.
This commit is the first half of the work to clean up this edge case.
All gdbpy_tui_window_maker objects (the objects that implement the
TUI window factory callback for Python defined TUI windows), are now
linked together into a global list using the intrusive list mechanism.
When GDB shuts down the Python interpreter we can now walk this global
list and release the reference that is held to the underlying Python
object. By releasing this reference the Python object will now be
deleted.
I've added a new assert in gdbpy_tui_window_maker::operator(), this
will catch the case where we somehow end up in here after having
reset the reference to the underlying Python object. I don't think
this should ever happen though as we only clear the references when
shutting down the Python interpreter, and the ::operator() function is
only called when trying to apply a new TUI layout - something that
shouldn't happen while GDB itself is shutting down.
This commit does not update the std::unordered_map in tui-layout.c,
that will be done in the next commit.
Reviewed-By: Tom Tromey <tom@tromey.com>
The documentation for gdb.register_window_type says:
"... It's an error to try to replace one of the built-in windows,
but other window types can be replaced. ..."
I take this to mean that if I imported a Python script like this:
gdb.register_window_type('my_window', FactoryFunction)
Then GDB would have a new TUI window 'my_window', which could be
created by calling FactoryFunction(). If I then, in the same GDB
session imported a script which included:
gdb.register_window_type('my_window', UpdatedFactoryFunction)
Then GDB would replace the old 'my_window' factory with my new one,
GDB would now call UpdatedFactoryFunction().
This is pretty useful in practice, as it allows users to iterate on
their window implementation within a single GDB session.
However, right now, this is not how GDB operates. The second call to
register_window_type is basically ignored and the old window factory
is retained.
This is because in tui_register_window (tui/tui-layout.c) we use
std::unordered_map::emplace to insert the new factory function, and
emplace doesn't replace an existing element in an unordered_map.
In this commit, before the emplace call, I now search for an already
existing element, and delete any matching element from the map, the
emplace call will then add the new factory function.
Reviewed-By: Tom Tromey <tom@tromey.com>
PR build/30108 concerns building gdb documentation with
--with-sytem-readline. If the in-tree readline directory is
missing, though, the docs will fail to build:
make[4]: Entering directory '/home/keiths/work/readline-doc-issue/linux/gdb/doc'
make[4]: *** No rule to make target '../../../src/gdb/doc/../../readline/readline/doc/rluser.texi', needed by 'gdb.info'. Stop.
The listed file (and hsuser.texi) are conditionally included by gdb.texinfo.
When system readline is used, gdb/configure.ac will leave
READLINE_TEXI_INCFLAGS empty, causing doc/Makefile.in to output a line to
$BUILD/doc/GDBvn.texi with "@set SYSTEM_READLINE". This surpresses the
inclusion of the missing files. They are not needed or used in this
scenario.
However, GDB_DOC_SOURCE_INCLUDES always lists these two files as dependencies,
thus provoking the build error whenever readline/ is missing.
This patch fixes this by creating (essentially) a conditional setting of the
dependencies to be included from readline.
the early-out in wild_sort is not enough, it might still be
that filenames are equal _and_ the wildcard list doesn't specify
a sort order either. Don't call compare_section then.
Tested on all targets.
Before commit:
commit 2438b771ee
Date: Wed Nov 2 15:53:43 2022 +0000
opcodes/mips: use .word/.short for undefined instructions
unknown 32-bit microMIPS instructions were disassembled as a raw
32-bit number with no '.word' directive. The above commit changed
this and added a '.word' directive before the 32-bit number.
It was pointed out on the mailing list, that for microMIPS it would be
better to display such 32-bit instructions using a '.short' directive
followed by two 16-bit values.
This commit updates the mips disassembler to do this, and adds a new
test that validates this output.
A new guile test added in commit:
commit 0a9ccb9dd7
Date: Mon Feb 6 13:04:16 2023 +0000
gdb: only allow one of thread or task on breakpoints or watchpoints
fails for some versions of guile. It turns out that some versions of
guile emit an error like this:
(gdb) guile (set-breakpoint-thread! bp 1)
ERROR: In procedure set-breakpoint-thread!:
In procedure gdbscm_set_breakpoint_thread_x: cannot set both task and thread attributes
Error while executing Scheme code.
while other versions of guile emit the error like this:
(gdb) guile (set-breakpoint-thread! bp 1)
ERROR: In procedure set-breakpoint-thread!:
ERROR: In procedure gdbscm_set_breakpoint_thread_x: cannot set both task and thread attributes
Error while executing Scheme code.
notice the extra 'ERROR: ' on the second line of output. This commit
updates the test regexp to handle this optional 'ERROR: ' string.
Move all the function local static state variables to file scope,
in order to tidy memory on exit and to reinit everything for that
annoying oss-fuzz. Also fix a couple memory leaks.
* read.h (read_begin, read_end): Declare.
* read.c (read_begin): Call stabs_begin.
(read_end): Call stabs_end.
* stabs.c (stabs_begin, stabs_end): New functions.
(in_dot_func_p): Delete, use current_function_label instead.
(cached_sec): Move from s_stab_generic.
(last_asm_file, file_label_count): Move from generate_asm_file.
(line_label_count, prev_lineno, prev_line_file): Move from
stabs_generate_asm_lineno.
(void_emitted_p): Move from stabs_generate_asm_func.
(endfunc_label_count): Move from stabs_generate_asm_endfunc.
(stabs_generate_asm_lineno): Simplify setting of
prev_line_file.
(stabs_generate_asm_func): Don't leak current_function_label.
(stabs_generate_asm_endfunc): Likewise.
If the hipcc compiler cannot be found in dejagnu's tool_root_dir, look
for it in $::env(ROCM_PATH) (if set). If hipcc is still not found,
fallback to "hipcc" so the compiler will be searched in the PATH. This
removes the fallback to the hard-coded "/opt/rocm/bin" prefix.
This change is done so ROCM tools are searched in a uniform manner.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
Update allow_hipcc_tests so all gdb.rocm tests are skipped if we do not
have a working hipcc compiler available.
To achieve this, adjust gdb_simple_compile to ensure that the hip
program is saved in a ".cpp" file before calling hipcc otherwise
compilation will fail.
One thing to note is that it is possible to have a hipcc installed with
a CUDA backend. Compiling with this back-end will successfully result
in an application, but GDB cannot debug it (at least for the offload
part). In the context of the gdb.rocm tests, we want to detect such
situation where gdb_simple_compile would give a false positive.
To achieve this, this patch checks that there is at least one AMDGPU
device available and that hipcc can compile for this or those targets.
Detecting the device is done using the rocm_agent_enumerator tool which
is installed with the all ROCm installations (it is used by hipcc to
detect identify targets if this is not specified on the comand line).
This patch also makes the allow_hipcc_tests proc a cached proc.
Co-Authored-By: Pedro Alves <pedro@palves.net>
Approved-By: Simon Marchi <simon.marchi@efficios.com>
Update allow_hipcc_tests to check that GDB has the amd-dbgapi support
built-in. Without this support, all tests using hipcc and the rocm
stack will fail.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
Rename skip_hipcc_tests to allow_hipcc_tests so it can be used as a
"require" predicate in tests.
Use require in gdb.rocm/simple.exp.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
Ensure that the "show configuration" command and the "--configuration"
command line switch shows if GDB was built with the AMDGPU support or
not.
This will be used in a later patch in this series.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
This fixes some objcopy memory leaks. commit 450da4bd38 used
xatexit to tidy most of the hash table memory, but of course that's
ineffective without a call to xexit. The other major memory leak
happens if there is an error of some sort writing the output file, due
to not closing the input file and thus not freeing memory attached to
the bfd.
* objcopy.c (copy_file): Don't return when bfd_close of output
gives an error, always bfd_close input too.
(main): Call xexit.
This patch introduces a new file, dwarf2/die.c, and moves some
DIE-related code out of dwarf2/read.c and into this new file. This is
just a small part of the long-term project to split up read.c.
(According to 'wc', dwarf2/read.c is the largest file in gdb by around
8000 LOC.)
Regression tested on x86-64 Fedora 36.
Commit:
commit 2ecee23675
CommitDate: Sun Feb 12 05:46:44 2023 +0000
gdb: use -1 for breakpoint::task default value
Failed to take account of an earlier commit:
commit f1f517e810
CommitDate: Sat Feb 11 17:36:24 2023 +0000
gdb: show task number in describe_other_breakpoints
That both of these are my own commits is only more embarrassing.
This small fix updates describe_other_breakpoints to take account of
the default task number now being -1. This fixes regressions in
gdb.base/break.exp, gdb.base/break-always.exp, and many other tests.
This commit should fix PR gdb/20091, PR gdb/17201, and PR gdb/17071.
Additionally, PR gdb/17199 relates to this area of code, but is more
of a request to refactor some parts of GDB, this commit does not
address that request, but it is probably worth reading that PR when
looking at this commit.
When the current language is C++, and the user places a breakpoint on
a function in a shared library, GDB will currently find two locations
for the breakpoint, one location will be within the function itself as
we would expect, but the other location will be within the PLT table
for the call to the named function. Consider this session:
$ gdb -q /tmp/breakpoint-shlib-func
Reading symbols from /tmp/breakpoint-shlib-func...
(gdb) start
Temporary breakpoint 1 at 0x40112e: file /tmp/breakpoint-shlib-func.cc, line 20.
Starting program: /tmp/breakpoint-shlib-func
Temporary breakpoint 1, main () at /tmp/breakpoint-shlib-func.cc:20
20 int answer = foo ();
(gdb) break foo
Breakpoint 2 at 0x401030 (2 locations)
(gdb) info breakpoints
Num Type Disp Enb Address What
2 breakpoint keep y <MULTIPLE>
2.1 y 0x0000000000401030 <foo()@plt>
2.2 y 0x00007ffff7fc50fd in foo() at /tmp/breakpoint-shlib-func-lib.cc:20
This is not the expected behaviour. If we compile the same test using
a C compiler then we see this:
(gdb) break foo
Breakpoint 2 at 0x7ffff7fc50fd: file /tmp/breakpoint-shlib-func-c-lib.c, line 20.
(gdb) info breakpoints
Num Type Disp Enb Address What
2 breakpoint keep y 0x00007ffff7fc50fd in foo at /tmp/breakpoint-shlib-func-c-lib.c:20
Here's what's happening. When GDB parses the symbols in the main
executable and the shared library we see a number of different symbols
for foo, and use these to create entries in GDB's msymbol table:
- In the main executable we see a symbol 'foo@plt' that points at
the plt entry for foo, from this we add two entries into GDB's
msymbol table, one called 'foo@plt' which points at the plt entry
and has type mst_text, then we create a second symbol, this time
called 'foo' with type mst_solib_trampoline which also points at
the plt entry,
- Then, when the shared library is loaded we see another symbol
called 'foo', this one points at the actual implementation in the
shared library. This time GDB creates a msymbol called 'foo' with
type mst_text that points at the implementation.
This means that GDB creates 3 msymbols to represent the 2 symbols
found in the executable and shared library.
When the user creates a breakpoint on 'foo' GDB eventually ends up in
search_minsyms_for_name (linespec.c), this function then calls
iterate_over_minimal_symbols passing in the name we are looking for
wrapped in a lookup_name_info object.
In iterate_over_minimal_symbols we iterate over two hash tables (using
the name we're looking for as the hash key), first we walk the hash
table of symbol linkage names, then we walk the hash table of
demangled symbol names.
When the language is C++ the symbols for 'foo' will all have been
mangled, as a result, in this case, the iteration of the linkage name
hash table will find no matching results.
However, when we walk the demangled hash table we do find some
results. In order to match symbol names, GDB obtains a symbol name
matching function by calling the get_symbol_name_matcher method on the
language_defn class. For C++, in this case, the matching function we
use is cp_fq_symbol_name_matches, which delegates the work to
strncmp_iw_with_mode with mode strncmp_iw_mode::MATCH_PARAMS and
language set to language_cplus.
The strncmp_iw_mode::MATCH_PARAMS mode means that strncmp_iw_mode will
skip any parameters in the demangled symbol name when checking for a
match, e.g. 'foo' will match the demangled name 'foo()'. The way this
is done is that the strings are matched character by character, but,
once the string we are looking for ('foo' here) is exhausted, if we
are looking at '(' then we consider the match a success.
Lets consider the 3 symbols GDB created. If the function declaration
is 'void foo ()' then from the main executable we added symbols
'_Z3foov@plt' and '_Z3foov', while from the shared library we added
another symbol call '_Z3foov'. When these are demangled they become
'foo()@plt', 'foo()', and 'foo()' respectively.
Now, the '_Z3foov' symbol from the main executable has the type
mst_solib_trampoline, and in search_minsyms_for_name, we search for
any symbols of type mst_solib_trampoline and filter these out of the
results.
However, the '_Z3foov@plt' symbol (from the main executable), and the
'_Z3foov' symbol (from the shared library) both have type mst_text.
During the demangled name matching, due to the use of MATCH_PARAMS
mode, we stop the comparison as soon as we hit a '(' in the demangled
name. And so, '_Z3foov@plt', which demangles to 'foo()@plt' matches
'foo', and '_Z3foov', which demangles to 'foo()' also matches 'foo'.
By contrast, for C, there are no demangled hash table entries to be
iterated over (in iterate_over_minimal_symbols), we only consider the
linkage name symbols which are 'foo@plt' and 'foo'. The plain 'foo'
symbol obviously matches when we are looking for 'foo', but in this
case the 'foo@plt' will not match due to the '@plt' suffix.
And so, when the user asks for a breakpoint in 'foo', and the language
is C, search_minsyms_for_name, returns a single msymbol, the mst_text
symbol for foo in the shared library, while, when the language is C++,
we get two results, '_Z3foov' for the shared library function, and
'_Z3foov@plt' for the plt entry in the main executable.
I propose to fix this in strncmp_iw_with_mode. When the mode is
MATCH_PARAMS, instead of stopping at a '(' and assuming the match is a
success, GDB will instead search forward for the matching, closing,
')', effectively skipping the parameter list, and then resume
matching. Thus, when comparing 'foo' to 'foo()@plt' GDB will
effectively compare against 'foo@plt' (skipping the parameter list),
and the match will fail, just as it does when the language is C.
There is one slight complication, which is revealed by the test
gdb.linespec/cpcompletion.exp, when searching for the symbol of a
const member function, the demangled symbol will have 'const' at the
end of its name, e.g.:
struct_with_const_overload::const_overload_fn() const
Previously, the matching would stop at the '(' character, but after my
change the whole '()' is skipped, and the match resumes. As a result,
the 'const' modifier results in a failure to match, when previously
GDB would have found a match.
To work around this issue, in strncmp_iw_with_mode, when mode is
MATCH_PARAMS, after skipping the parameter list, if the next character
is '@' then we assume we are looking at something like '@plt' and
return a value indicating the match failed, otherwise, we return a
value indicating the match succeeded, this allows things like 'const'
to be skipped.
With these changes in place I now see GDB correctly setting a
breakpoint only at the implementation of 'foo' in the shared library.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=20091
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=17201
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=17071
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=17199
Tested-By: Bruno Larsen <blarsen@redhat.com>
Approved-By: Simon Marchi <simon.marchi@efficios.com>
Within the breakpoint struct we have two fields ::thread and ::task
which are used for thread or task specific breakpoints. When a
breakpoint doesn't have a specific thread or task then these fields
have the values -1 and 0 respectively.
There's no particular reason (as far as I can tell) why these two
"default" values are different, and I find the difference a little
confusing. Long term I'd like to potentially fold these two fields
into a single field, but that isn't what this commit does.
What this commit does is switch to using -1 as the "default" value for
both fields, this means that the default for breakpoint::task has
changed from 0 to -1. I've updated all the code I can find that
relied on the value of 0, and I see no test regressions, especially in
gdb.ada/tasks.exp, which still fully passes.
There should be no user visible changes after this commit.
Approved-By: Pedro Alves <pedro@palves.net>
After this mailing list posting:
https://sourceware.org/pipermail/gdb-patches/2023-February/196607.html
it seems to me that in practice an Ada task maps 1:1 with a GDB
thread, and so it doesn't really make sense to allow uses to give both
a thread and a task within a single breakpoint or watchpoint
condition.
This commit updates GDB so that the user will get an error if both
are specified.
I've added new tests to cover the CLI as well as the Python and Guile
APIs. For the Python and Guile testing, as far as I can tell, this
was the first testing for this corner of the APIs, so I ended up
adding more than just a single test.
For documentation I've added a NEWS entry, but I've not added anything
to the docs themselves. Currently we document the commands with a
thread-id or task-id as distinct command, e.g.:
'break LOCSPEC task TASKNO'
'break LOCSPEC task TASKNO if ...'
'break LOCSPEC thread THREAD-ID'
'break LOCSPEC thread THREAD-ID if ...'
As such, I don't believe there is any indication that combining 'task'
and 'thread' would be expected to work; it seems clear to me in the
above that those four options are all distinct commands.
I think the NEWS entry is enough that if someone is combining these
keywords (it's not clear what the expected behaviour would be in this
case) then they can figure out that this was a deliberate change in
GDB, but for a new user, the manual doesn't suggest combining them is
OK, and any future attempt to combine them will give an error.
Approved-By: Pedro Alves <pedro@palves.net>
I noticed that describe_other_breakpoints doesn't show the task
number, but does show the thread-id. I can't see any reason why we'd
want to not show the task number in this situation, so this commit
adds this missing information, and extends gdb.ada/tasks.exp to check
this case.
Approved-By: Pedro Alves <pedro@palves.net>
I noticed that describe_other_breakpoints was printing the global
thread-id to the CLI. For CLI output we should be printing the
inferior local thread-id (e.g. "2.1"). This can be seen in the
following GDB session:
(gdb) info threads
Id Target Id Frame
1.1 Thread 4065742.4065742 "bp-thread-speci" main () at /tmp/bp-thread-specific.c:27
* 2.1 Thread 4065743.4065743 "bp-thread-speci" main () at /tmp/bp-thread-specific.c:27
(gdb) break foo thread 2.1
Breakpoint 3 at 0x40110a: foo. (2 locations)
(gdb) break foo thread 1.1
Note: breakpoint 3 (thread 2) also set at pc 0x40110a.
Note: breakpoint 3 (thread 2) also set at pc 0x40110a.
Breakpoint 4 at 0x40110a: foo. (2 locations)
Notice that GDB says:
Note: breakpoint 3 (thread 2) also set at pc 0x40110a.
The 'thread 2' in here is using the global thread-id, we should
instead say 'thread 2.1' which corresponds to how the user specified
the breakpoint.
This commit fixes this issue and adds a test.
Approved-By: Pedro Alves <pedro@palves.net>
The test added in this commit tests for a long fixed readline issue
relating to long command lines. A similar patch has existed in the
Fedora GDB tree for several years, but I don't see any reason why this
test would not be suitable for inclusion in upstream GDB. I've
updated the patch to current testsuite standards.
The test is checking for an issue that was fixed by this readline
patch:
https://lists.gnu.org/archive/html/bug-readline/2006-11/msg00002.html
Which was merged into readline 6.0 (released ~2010). The issue was
triggered when the user enters a long command line, which wrapped over
multiple terminal lines. The crash looks like this:
free(): invalid pointer
Fatal signal: Aborted
----- Backtrace -----
0x4fb583 gdb_internal_backtrace_1
../../src/gdb/bt-utils.c:122
0x4fb583 _Z22gdb_internal_backtracev
../../src/gdb/bt-utils.c:168
0x6047b9 handle_fatal_signal
../../src/gdb/event-top.c:964
0x7f26e0cc56af ???
0x7f26e0cc5625 ???
0x7f26e0cae8d8 ???
0x7f26e0d094be ???
0x7f26e0d10aab ???
0x7f26e0d124ab ???
0x7f26e1d32e12 rl_free_undo_list
../../readline-5.2/undo.c:119
0x7f26e1d229eb readline_internal_teardown
../../readline-5.2/readline.c:405
0x7f26e1d3425f rl_callback_read_char
../../readline-5.2/callback.c:197
0x604c0d gdb_rl_callback_read_char_wrapper_noexcept
../../src/gdb/event-top.c:192
0x60581d gdb_rl_callback_read_char_wrapper
../../src/gdb/event-top.c:225
0x60492f stdin_event_handler
../../src/gdb/event-top.c:545
0xa60015 gdb_wait_for_event
../../src/gdbsupport/event-loop.cc:694
0xa6078d gdb_wait_for_event
../../src/gdbsupport/event-loop.cc:593
0xa6078d _Z16gdb_do_one_eventi
../../src/gdbsupport/event-loop.cc:264
0x6fc459 start_event_loop
../../src/gdb/main.c:411
0x6fc459 captured_command_loop
../../src/gdb/main.c:471
0x6fdce4 captured_main
../../src/gdb/main.c:1310
0x6fdce4 _Z8gdb_mainP18captured_main_args
../../src/gdb/main.c:1325
0x44f694 main
../../src/gdb/gdb.c:32
---------------------
I recreated the above crash by a little light hacking on GDB, and then
linking GDB against readline 5.2. The above stack trace was generated
from the test included in this patch, and matches the trace that was
included in the original bug report.
It is worth acknowledging that without hacking things GDB has a
minimum requirement of readline 7.0. This test is not about checking
whether GDB has been built against an older version of readline, it is
about checking that readline doesn't regress in this area.
Reviewed-By: Tom Tromey <tom@tromey.com>
While debugging GDB I used 'show directories' and spotted lots of
entries that didn't make much sense. Here are all the entries that are
in my directories list:
/tmp/binutils-gdb/build
/tmp/binutils-gdb/build/../../src/gdb
/tmp/binutils-gdb/build/../../src/gdb/../bfd
/tmp/binutils-gdb/build/../../src/gdb/../libiberty
$cdir
$cwd
Notice the second, third, and fourth entries in this list, these
should really be:
/tmp/binutils-gdb/build/../src/gdb
/tmp/binutils-gdb/build/../src/gdb/../bfd
/tmp/binutils-gdb/build/../src/gdb/../libiberty
The problem is because I generally run everything from the top level
build directory, not the gdb/ sub-directory, thus, I start GDB like:
./gdb/gdb --data-directory ./gdb/data-directory
If run GDB under GDB, then I end up loading the gdb/gdb-gdb.gdb
script, which contains these lines:
dir ../../src/gdb/../libiberty
dir ../../src/gdb/../bfd
dir ../../src/gdb
dir .
These commands only make sense when running within the gdb/
sub-directory.
However, my debugging experience doesn't seem to be degraded at all, I
can still see the GDB source code just fine; which is because the
directory list still contains $cdir.
The build/gdb/gdb-gdb.gdb script is created from the
src/gdb/gdb-gdb.gdb.in template, which includes the automake @srcdir@
markers.
The 'dir' commands have mostly been around since the sourceware
repository was first created, though this commit 67f0714670 did
reorder some of the 'dir' commands, which would seem to indicate these
commands were important to some people, at some time.
One possible fix would be to replace @srcdir@ with @abs_srcdir@, this
would ensure that the entries added were all valid, no matter the
user's current directory when debugging GDB.
However... I'd like to propose that we instead remove all the extra
directories completely. My hope is that, with more recent tools, the
debug information should allow us to correctly find all of the source
files without having to add any extra 'dir' entries. Obviously,
commit 67f0714670 does make me a little nervous, but the
gdb-gdb.gdb script isn't something a non-maintainer will be using, so
I think we can afford to be a little more aggressive here. If it
turns out the 'dir' entries are needed then we can add them back, but
actually document why they are needed. Plus, when we add them back we
will use @abs_srcdir@ instead of @srcdir@.
Reviewed-By: Tom Tromey <tom@tromey.com>
For i386 we have these unwinders:
...
$ gdb -q -batch -ex "set arch i386" -ex "maint info frame-unwinders"
The target architecture is set to "i386".
dummy DUMMY_FRAME
dwarf2 tailcall TAILCALL_FRAME
inline INLINE_FRAME
i386 epilogue NORMAL_FRAME
dwarf2 NORMAL_FRAME
dwarf2 signal SIGTRAMP_FRAME
i386 stack tramp NORMAL_FRAME
i386 sigtramp SIGTRAMP_FRAME
i386 prologue NORMAL_FRAME
...
and for amd64:
...
$ gdb -q -batch -ex "set arch i386:x86-64" -ex "maint info frame-unwinders"
The target architecture is set to "i386:x86-64".
dummy DUMMY_FRAME
dwarf2 tailcall TAILCALL_FRAME
inline INLINE_FRAME
python NORMAL_FRAME
amd64 epilogue NORMAL_FRAME
i386 epilogue NORMAL_FRAME
dwarf2 NORMAL_FRAME
dwarf2 signal SIGTRAMP_FRAME
amd64 sigtramp SIGTRAMP_FRAME
amd64 prologue NORMAL_FRAME
i386 stack tramp NORMAL_FRAME
i386 sigtramp SIGTRAMP_FRAME
i386 prologue NORMAL_FRAME
...
ISTM me there's no reason for the i386 unwinders to be there for amd64.
Furthermore, there's a generic need to play around with enabling and disabling
unwinders, see PR8434. Currently, that's only available for both the dwarf2
unwinders at once using "maint set dwarf unwinders on/off".
If I manually disable the "amd64 epilogue" unwinder, the "i386 epilogue"
unwinder becomes active and gives the wrong answer, while I'm actually
interested in the result of the dwarf2 unwinder. Of course I can also
manually disable the "i386 epilogue", but I take the fact that I have to do
that as evidence that on amd64, the "i386 epilogue" is not only unnecessary,
but in the way.
Fix this by only adding the i386 unwinders if
"info.bfd_arch_info->bits_per_word == 32".
Note that the x32 abi (x86_64/-mx32):
- has the same unwinder list as amd64 (x86_64/-m64) before this commit,
- has info.bfd_arch_info->bits_per_word == 64, the same as amd64, and
consequently,
- has the same unwinder list as amd64 after this commit.
Tested on x86_64-linux, -m64 and -m32. Not tested with -mx32.
Reviewed-By: John Baldwin <jhb@freebsd.org>
PR tdep/30102
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30102
There is some inconsistency between the behaviour of objdump -D and
objdump -s, both supposedly operating on all sections by default.
objdump -s ignores bss sections, while objdump -D dissassembles the
zeros. Fix this by making objdump -D ignore bss sections too.
Furthermore, "objdump -s -j .bss" doesn't dump .bss as it should,
since the user is specifically asking to look at all those zeros.
This change does find some tests that used objdump -D with expected
output in bss-style sections. I've updated all the msp430 tests that
just wanted to find a non-empty section to look at section headers
instead, making the tests slightly more stringent. The ppc xcoff and
spu tests are fixed by adding -j options to objdump, which makes the
tests somewhat more lenient.
binutils/
* objdump.c (disassemble_section): Ignore sections without
contents, unless overridden by -j.
(dump_section): Allow -j to override the default of not
displaying sections without contents.
* doc/binutils.texi (objdump options): Update -D, -s and -j
description.
gas/
* testsuite/gas/ppc/xcoff-tls-32.d: Select wanted objdump
sections with -j.
* testsuite/gas/ppc/xcoff-tls-64.d: Likewise.
ld/
* testsuite/ld-msp430-elf/main-bss-lower.d,
* testsuite/ld-msp430-elf/main-bss-upper.d,
* testsuite/ld-msp430-elf/main-const-lower.d,
* testsuite/ld-msp430-elf/main-const-upper.d,
* testsuite/ld-msp430-elf/main-text-lower.d,
* testsuite/ld-msp430-elf/main-text-upper.d,
* testsuite/ld-msp430-elf/main-var-lower.d,
* testsuite/ld-msp430-elf/main-var-upper.d: Expect -wh output.
* testsuite/ld-msp430-elf/msp430-elf.exp: Use objdump -wh
rather than objdump -D or objdump -d with tests checking for
non-empty given sections.
* testsuite/ld-spu/ear.d,
* testsuite/ld-spu/icache1.d,
* testsuite/ld-spu/ovl.d,
* testsuite/ld-spu/ovl2.d: Select wanted objdump sections.
open_source_file relies on errno to communicate the reason for a missing
source file.
open_source_file may also call debuginfod_find_source. It is possible
for debuginfod_find_source to set errno to a value unrelated to the
reason for a failed download.
This can result in bogus error messages being reported as the reason for
a missing source file. The following error message should instead be
"No such file or directory":
Temporary breakpoint 1, 0x00005555556f4de0 in main ()
(gdb) list
Downloading source file /usr/src/debug/glibc-2.36-8.fc37.x86_64/elf/<built-in>
1 /usr/src/debug/glibc-2.36-8.fc37.x86_64/elf/<built-in>: Directory not empty.
Fix this by having open_source_file return a negative errno if it fails
to open a source file. Use this value to generate the error message
instead of errno.
Approved-By: Tom Tromey <tom@tromey.com>
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29999
gdbsupport/errors.h declares perror_with_name and leaves the
implementation to the clients.
However gdb and gdbserver's implementations are essentially the
same, resulting in unnecessary code duplication.
Fix this by implementing perror_with_name in gdbsupport. Add an
optional parameter for specifying the errno used to generate the
error message.
Also move the implementation of perror_string to gdbsupport since
perror_with_name requires it.
Approved-By: Tom Tromey <tom@tromey.com>
This commit introduces the idea of loading only part of an array in
order to print it, what I call "limited length" arrays.
The motivation behind this work is to make it possible to print slices
of very large arrays, where very large means bigger than
`max-value-size'.
Consider this GDB session with the current GDB:
(gdb) set max-value-size 100
(gdb) p large_1d_array
value requires 400 bytes, which is more than max-value-size
(gdb) p -elements 10 -- large_1d_array
value requires 400 bytes, which is more than max-value-size
notice that the request to print 10 elements still fails, even though 10
elements should be less than the max-value-size. With a patched version
of GDB:
(gdb) p -elements 10 -- large_1d_array
$1 = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9...}
So now the print has succeeded. It also has loaded `max-value-size'
worth of data into value history, so the recorded value can be accessed
consistently:
(gdb) p -elements 10 -- $1
$2 = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9...}
(gdb) p $1
$3 = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
20, 21, 22, 23, 24, <unavailable> <repeats 75 times>}
(gdb)
Accesses with other languages work similarly, although for Ada only
C-style [] array element/dimension accesses use history. For both Ada
and Fortran () array element/dimension accesses go straight to the
inferior, bypassing the value history just as with C pointers.
Co-Authored-By: Maciej W. Rozycki <macro@embecosm.com>
Add a `-nonl' option to `gdb_test' making it possible to match output
from commands such as `output' that do not produce a new line sequence
at the end, e.g.:
(gdb) output 0
0(gdb)
While it makes sense to allow accessing out-of-bounds elements in the
debuggee and see whatever there might happen to be there in memory (we
are a debugger and not a programming rules enforcement facility and we
want to make people's life easier in chasing bugs), e.g.:
(gdb) print one_hundred[-1]
$1 = 0
(gdb) print one_hundred[100]
$2 = 0
(gdb)
we shouldn't really pretend that we have any meaningful data around
values recorded in history (what these commands really retrieve are
current debuggee memory contents outside the original data accessed,
really confusing in my opinion). Mark values recorded in history as
such then and verify accesses to be in-range for them:
(gdb) print one_hundred[-1]
$1 = <unavailable>
(gdb) print one_hundred[100]
$2 = <unavailable>
Add a suitable test case, which also covers integer overflows in data
location calculation.
Approved-By: Tom Tromey <tom@tromey.com>
