Commit Graph

11462 Commits

Author SHA1 Message Date
Guinevere Larsen
ab8c2180a3 gdb/record: introduce recoding support for vpor
This commit adds recording support for the AVX instruction vpor, and the
AVX2 extension. Since the encoding of vpor and vpxor are the same, and
their semantics are basically the same, modulo the mathematical
operation, they are handled by the same switch case block.

This also updates the vpxor function, to test vpor and vpxor, and
updates the name to vpor_xor_test to better reflect what it does.

Approved-By: Tom Tromey <tom@tromey.com>
2024-11-22 17:40:26 -03:00
Guinevere Larsen
b19c86e2db gdb/record: Add support for recording vpmovmskb
This commit adds support for recording the AVX instruction vpmovmskb,
and tests to the relevant file. The test didn't really support checking
general purpose registers, so this commit also adds a proc to
gdb.reverse/i386-avx-reverse.exp, which can be used to test them

Approved-By: Tom Tromey <tom@tromey.com>
2024-11-22 17:40:25 -03:00
Guinevere Larsen
f21055a4e9 gdb/record: Add support for all vpcmpeq instructions
This commit adds support to recording instructions of the form
VPCMPEQ[B|W|D]. They are all encoded in the same way and only
differentiated by the opcode, so they are all processed together. This
commit also updates the test to (quite exhaustively) test the new
instruction.

Approved-By: Tom Tromey <tom@tromey.com>
2024-11-22 17:40:25 -03:00
Guinevere Larsen
2bb2f15e0b gdb/record: add support for vpxor instruction
This commit adds support for recording the instruction vpxor,
introduced in the AVX extension, and extended in AVX2 to use 256 bit
registers. The test gdb.reverse/i386-avx-reverse.exp has been extended
to test this instruction as well.

Approved-By: Tom Tromey <tom@tromey.com>
2024-11-22 17:40:25 -03:00
Tom de Vries
372d0a4c96 [gdb/python] Handle failure to initialize without exiting
I tried out making python initialization fail by passing an incorrect
PYTHONHOME, and got:
...
$ PYTHONHOME=foo ./gdb.sh -q
Python path configuration:
  PYTHONHOME = 'foo'
  ...
Python initialization failed: \
  failed to get the Python codec of the filesystem encoding
Python not initialized
$
...

The relevant part of the code is:
...
static void
gdbpy_initialize (const struct extension_language_defn *extlang)
{
  if (!do_start_initialization () && py_isinitialized && PyErr_Occurred ())
    gdbpy_print_stack ();

   gdbpy_enter enter_py;
...

What happens is:
- gdbpy_enter::gdbpy_enter () is called, where we run into:
  'if (!gdb_python_initialized) error (_("Python not initialized"));'
- the error propagates to gdb's toplevel
- gdb print the error and exits.

It seems unnecesssary that we exit gdb.  We could continue the
session without python support.

Fix this by:
- bailing out of gdbpy_initialize if !do_start_initialization
- bailing out of finalize_python if !gdb_python_initialized

This gets us instead:
...
$ PYTHONHOME=foo gdb -q
Python path configuration:
  PYTHONHOME = 'foo'
  ...
Python initialization failed: \
  failed to get the Python codec of the filesystem encoding
(gdb) python print (1)
Python not initialized
(gdb)
...

Tested on aarch64-linux.

Approved-By: Tom Tromey <tom@tromey.com>
2024-11-22 19:34:24 +01:00
Andrew Burgess
26522e3480 gdb/disasm: fix demangling when disassembling the current function
When disassembling function symbols in C++ code, if GDB is asked to
disassemble a function by name then the function name in the header
line can be demangled by turning on `set print asm-demangle on`, e.g.:

  (gdb) disassemble foo_type::some_function
  Dump of assembler code for function _ZN8foo_type13some_functionE7my_type:
     0x0000000000401142 <+0>:	push   %rbp
     ... etc ...
  End of assembler dump.
  (gdb) set print asm-demangle on
  (gdb) disassemble foo_type::some_function
  Dump of assembler code for function foo_type::some_function(my_type):
     0x0000000000401142 <+0>:	push   %rbp
     ... etc ...                                                        │
  End of assembler dump.                                                │

However, if GDB is disassembling the current function, then this
demangling doesn't work, e.g.:

  (gdb) break foo_type::some_function
  Breakpoint 1 at 0x401152: file mangle.cc, line 16.
  (gdb) run
  Starting program: /tmp/mangle

  Breakpoint 1, foo_type::some_function (this=0x7fffffffa597, obj=...) at mangle.cc:16
  16	    obj.update ();
  (gdb) disassemble
  Dump of assembler code for function _ZN8foo_type13some_functionE7my_type:
     0x0000000000401142 <+0>:	push   %rbp
     ... etc ...
  End of assembler dump.
  (gdb) set print asm-demangle on
  (gdb) disassemble
  Dump of assembler code for function _ZN8foo_type13some_functionE7my_type:
     0x0000000000401142 <+0>:	push   %rbp
     ... etc ...
  End of assembler dump.

This commit fixes this issue, and extends gdb.cp/disasm-func-name.exp,
which was already testing the first case (disassemble by name) to also
cover disassembling the current function.

Approved-By: Tom Tromey <tom@tromey.com>
2024-11-22 16:36:07 +00:00
Tom de Vries
2e61ad32ab [gdb/testsuite] Require local host in gdb.base/bg-exec-sigint-bp-cond.exp
I noticed that gdb.base/bg-exec-sigint-bp-cond.exp fails for remote host
(concretely, host board local-remote-host and target board
remote-gdbserver-on-localhost):
...
(gdb) c&^M
Continuing.^M
(gdb) bash: line 0: kill: (23834) - Operation not permitted^M
^M
Breakpoint 2, foo () at bg-exec-sigint-bp-cond.c:23^M
23        return 0;^M
...
due to getting gdb's pid like this:
...
    set gdb_pid [exp_pid -i [board_info host fileid]]
...

For remote host using ssh, this returns the pid of the ssh session on build.

Fix this by requiring local host.

Tested on x86_64-linux.
2024-11-22 13:37:24 +01:00
Tom de Vries
b200576fa0 [gdb/testsuite] Fix gdb.base/bg-exec-sigint-bp-cond.exp for signal merging
The test-case gdb.base/bg-exec-sigint-bp-cond.exp sends 10 SIGINTS to gdb, and
counts whether 10 have arrived.

Occasionally, less than 10 arrive due to signal merging [1].

This is more likely to happen when building gdb with -fsanitize=thread.

Fix this by instead, sending one SIGINT at a time, and waiting for it to
arrive.

This still makes the test-case fail if the fix fixing the PR that the
test-case was introduced for is reverted.

Tested on aarch64-linux and x86_64-linux.

PR testsuite/32329
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=32329

[1] https://www.gnu.org/software/libc/manual/html_node/Merged-Signals.html
2024-11-22 13:37:24 +01:00
Tom Tromey
29e316d8b1 Don't put JIT_READER_DIR into help text
The 80-column-help-string self-test can fail if gdb's install
directory is too long, because the help for "jit-reader-load" includes
JIT_READER_DIR.

This help text is actually somewhat misleading, though.
JIT_READER_DIR is not actually used directly -- instead the relocated
variant is used.

This patch adds a new "show jit-reader-directory" command and changes
the help text to refer to this instead.  I considered adding a "set"
command as well, but since absolute paths are acceptable here, and
since this is a very niche command anyway, I figured there was no need
to bother.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=32357
Reviewed-By: Kévin Le Gouguec <legouguec@adacore.com>
Reviewed-By: Eli Zaretskii <eliz@gnu.org>
Approved-By: Andrew Burgess <aburgess@redhat.com>
2024-11-21 14:08:18 -07:00
Andrew Burgess
9783247189 gdb/build-id: protect against weirdly short build-ids
While looking at build_id_to_bfd_suffix (in gdb/build-id.c) I realised
that GDB would likely not do what we wanted if a build-id was ever a
single byte.

Right now, build-ids generated by the GNU linker are 32 bytes, but
there's nothing that forces this to be the case, it's pretty easy to
create a fake, single byte, build-id.  Given that the build-id is an
external input (read from the objfile), GDB should protect itself
against these edge cases.

The problem with build_id_to_bfd_suffix is that this function creates
the path used to lookup either the debug information, or an
executable, based on its build-id.  So a 3-byte build-id 0xaabbcc will
look in the path: `$DEBUG_FILE_DIRECTORY/.build-id/aa/bbcc.debug`.
However, a single byte build-id 0xaa, will look in the file:
`$DEBUG_FILE_DIRECTORY/.build-id/aa/.debug` which doesn't seem right.

Worse, when looking for an objfile given a build-id GDB will look for
a file called `$DEBUG_FILE_DIRECTORY/.build-id/aa/` with a trailing
'/' character.

I propose that, in build_id_to_bfd_suffix we just return early if the
build-id is 1 byte (or less) with a return value that indicates no
separate file was found.

For testing I made use of the DWARF assembler.  I needed to update the
build-id creation proc, the existing code assumes that the build-id is
a multiple of 4 bytes, so I added some additional padding to ensure
that the generated note was a multiple of 4 bytes, even if the
build-id was not.

I added a test with a 1 byte build-id, and also for the case where the
build-id has zero length.  The zero length case already does what
you'd expect (no debug is loaded) as the bfd library rejects the
build-id when loading it from the objfile, but adding this additional
test is pretty cheap.

Approved-By: Kevin Buettner <kevinb@redhat.com>
2024-11-21 19:38:39 +00:00
Rohr, Stephan
be740e7cc6 testsuite: skip confirmation in 'gdb_reinitialize_dir'
Some shells automatically confirm the 'dir' command:

  (gdb) dir
  Reinitialize source path to empty? (y or n)
    [answered Y; input not from terminal]
  Source directories searched: $cdir;$cwd
  (gdb) y
  dir <...>/gdb/testsuite/gdb.base
  Undefined command: "y".  Try "help".

For example, this reprdocues in a MinGW32 environment with
'TERM=dumb'.  Skip sending 'y' if the command is already confirmed.

Approved-By: Tom Tromey <tom@tromey.com>
2024-11-21 00:49:39 -08:00
Tom Tromey
b6f3ac06ee Improve choice sorting in ada-lang.c
ada-lang.c has a "sort_choices" function that claims to sort the
symbol choices, but which does not really implement sorting.  This
patch changes this code to really sort the result vector, sorting
first by filename, then line number, and finally by the symbol name.

The filename sorting is done first by comparing basenames.  It turns
out that gnatmake and gprbuild invoke the compiler a bit differently,
so depending on which one you use, the results of a naive sort might
be different (due to the use of absolute or relative paths).
2024-11-20 13:18:40 -07:00
Christina Schimpe
27e82ad68b LAM: Enable tagged pointer support for watchpoints.
The Intel (R) linear address masking (LAM) feature modifies the checking
applied to 64-bit linear addresses.  With this so-called "modified
canonicality check" the processor masks the metadata bits in a pointer
before using it as a linear address.  LAM supports two different modes that
differ regarding which pointer bits are masked and can be used for
metadata: LAM 48 resulting in a LAM width of 15 and LAM 57 resulting in a
LAM width of 6.

This patch adjusts watchpoint addresses based on the currently enabled
LAM mode using the untag mask provided in the /proc/<pid>/status file.
As LAM can be enabled at runtime or as the configuration may change
when entering an enclave, GDB checks enablement state each time a watchpoint
is updated.

In contrast to the patch implemented for ARM's Top Byte Ignore "Clear
non-significant bits of address on memory access", it is not necessary to
adjust addresses before they are passed to the target layer cache, as
for LAM tagged pointers are supported by the system call to read memory.
Additionally, LAM applies only to addresses used for data accesses.
Thus, it is sufficient to mask addresses used for watchpoints.

The following examples are based on a LAM57 enabled program.
Before this patch tagged pointers were not supported for watchpoints:
~~~
(gdb) print pi_tagged
$2 = (int *) 0x10007ffffffffe004
(gdb) watch *pi_tagged
Hardware watchpoint 2: *pi_tagged
(gdb) c
Continuing.
Couldn't write debug register: Invalid argument.
~~~~

Once LAM 48 or LAM 57 is enabled for the current program, GDB can now
specify watchpoints for tagged addresses with LAM width 15 or 6,
respectively.

Approved-By: Felix Willgerodt <felix.willgerodt@intel.com>
2024-11-18 13:36:16 +00:00
Ijaz, Abdul B
9dc89f2b27 gdb: Update linkage name lookup function to allow mst_file_data/bss types.
From the commit 667ed4b14d onward, instead
of normal name GDB looks for the "jit_descriptor" linkage name in the JIT
code initialization.  Without this change, the function
"lookup_minimal_symbol_linkage", only matches the non-static data.  So in
case jit_debugger is static type then setting up breakpoint in the JIT code
fails.  Issue is seen for the intel compilers, where jit_debug_descriptor has
static type i.e. "mst_file_data".  Hence lookup_minimal_symbol_linkage returns
nullptr for it.  So, in this case breakpoint does not hit in the JIT code.
To resolve this, the commit introduces a new boolean argument to the
lookup_minimal_symbol_linkage function.  This argument allows the function to
also match mst_file_data and mst_file_bss types when set to true.  The
function is called with this new argument set to true only from JIT code
initialization handling, ensuring that the current behavior remains unchanged
for other cases.  Because handling of static types of data symbols for all cases
result in regression for "gdb.base/print-file-var.exp" test.

Example of minsym for the JIT code emitted by the intel compilers where
lookup_minimal_symbol_linkage fails without this change because jit_debugger
type is "mst_file_data".

(top-gdb) p *msymbol
$1 = {<general_symbol_info> =
{m_name = 0x7fffcc77dc95 "__jit_debug_descriptor",
m_value = {ivalue = 84325936, block = 0x506b630,
bytes = 0x506b630 <error: Cannot access memory at address 0x506b630>,
address = 0x506b630, unrel_addr = (unknown: 0x506b630),
common_block = 0x506b630, chain = 0x506b630},
language_specific = {obstack = 0x0, demangled_name = 0x0},
m_language = language_unknown, ada_mangled = 0, m_section = 29},
m_size = 24, filename = 0x55555a751b70 "JITLoaderGDB.cpp",
m_type = mst_file_data, created_by_gdb = 0,
m_target_flag_1 = 0, m_target_flag_2 = 0, m_has_size = 1,
name_set = 1, hash_next = 0x55555b86e4f0, demangled_hash_next = 0x0}

Updated the test "jit-elf-so.exp" to test the static type of jit_descriptor
object.

Approved-By: Tom Tromey <tom@tromey.com>
2024-11-17 02:02:11 +01:00
Andrew Burgess
82eff6743b gdb/testsuite: skip gdb.opt/inline-entry.exp for gcc 7 and older
It was pointed out that the recently added gdb.opt/inline-entry.exp
test would fail when run using gcc 7 and earlier, on an x86-64 target:

  https://inbox.sourceware.org/gdb-patches/9fe35ea1-d99b-444d-bd1b-e3a1f108dd77@suse.de

Bernd Edlinger points out that, for gcc, the test relies on the
-gstatement-frontiers work which was added in gcc 8.x:

  https://inbox.sourceware.org/gdb-patches/DU2PR08MB10263357597688D9D66EA745CE4242@DU2PR08MB10263.eurprd08.prod.outlook.com

For gcc 7.x and older, without the -gstatement-frontiers work, the
compiler uses DW_AT_entry_pc differently, which leads to a poorer
debug experience.

Here is the interesting source line from inline-entry.c:

  if ((global && bar (1)) || bar (2))

And here's some of the relevant disassembly output:

  Dump of assembler code for function main:
     0x401020 <+0>:	mov    0x3006(%rip),%eax	(1)
     0x401026 <+6>:	test   %eax,%eax		(2)
     0x401028 <+8>:	mov    0x2ffe(%rip),%eax	(3)
     0x40102e <+14>:	je     0x401038 <main+24>	(4)
     0x401030 <+16>:	sub    $0x1,%eax		(5)
     0x401033 <+19>:	jne    0x40103d <main+29>	(6)

Lines (1), (2), and (4) represent the check of 'global'.  However,
line (3) is actually the first instruction for 'bar' which has been
inlined.  Lines (5) and (6) are also part of the first inlined 'bar'
function.

If the check of 'global' returns false then the first call to 'bar'
should never happen, this is accomplished by the branch at (4) being
taken.

For gcc 8+, gcc generates a DW_AT_entry_pc with the value 0x401030,
this is where GDB places a breakpoint for 'bar', and this address is
after the branch at line (4), and so, if the call to 'bar' never
happens, the breakpoint is never hit.

For gcc 7 and older, gcc generates a DW_AT_entry_pc with the value
0x401028, which is the first address associated with the inline 'bar'
function.  Unfortunately, this address is also before the check of
'global' has completed, this means that GDB hits the 'bar' breakpoint
before the inferior has decided if 'bar' should actually be called or
not.

I don't think there's really much GDB can do in the older gcc
versions, we are placing the breakpoint at the entry point, and this
is within bar.  Given that this test does really depend on the newer
gcc behaviour, I think the only sensible solution is to skip this test
when an older version of gcc is being used.

I've incorporated the check for -gstatement-frontiers support that
Bernd suggested and now the test will be skipped for older versions of
GCC.

Approved-By: Tom de Vries <tdevries@suse.de>
2024-11-15 19:22:13 +00:00
Andrew Burgess
8518ce5fc2 gdb/python: missing PyObject_IsTrue error check in bppy_init
As with the previous two commits, this commit fixes a location where
we called PyObject_IsTrue without including an error check, this time
in bppy_init.

The 'qualified' argument is supposed to be a bool, the docs say:

  The optional QUALIFIED argument is a boolean that allows
  interpreting the function passed in 'spec' as a fully-qualified
  name.  It is equivalent to 'break''s '-qualified' flag (*note
  Linespec Locations:: and *note Explicit Locations::).

It's not totally clear that the only valid values are True or False,
but I'm choosing to interpret the docs that way, and so I've added a
PyBool_Type check during argument parsing.  Now, if a non-bool is
passed the user will get a TypeError during argument parsing.  I've
added a test to cover this case.

This is a potentially breaking change to the Python API, but hopefully
this will not impact too many people.  I've added a NEWS entry to
highlight this change.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>
Approved-By: Tom Tromey <tom@tromey.com>
2024-11-14 19:34:44 +00:00
Andrew Burgess
ad39b4aae8 gdb/python: missing PyObject_IsTrue error check in micmdpy_set_installed
Like the previous commit, I discovered that in micmdpy_set_installed
we were calling PyObject_IsTrue, but not checking for a possible error
value being returned.

The micmdpy_set_installed function implements the
gdb.MICommand.installed attribute, and the documentation indicates that
this attribute should only be assigned a bool:

  This attribute is read-write, setting this attribute to 'False'
  will uninstall the command, removing it from the set of available
  commands.  Setting this attribute to 'True' will install the
  command for use.

So I propose that instead of using PyObject_IsTrue we use
PyBool_Check, and if the new value fails this check we raise an
error.  We can then compare the new value to Py_True directly instead
of calling PyObject_IsTrue.

This is a potentially breaking change to the Python API, but hopefully
this will not impact too many people, and the fix is pretty
easy (switch to using a bool).  I've added a NEWS entry to draw
attention to this change.

Approved-By: Tom Tromey <tom@tromey.com>
2024-11-14 19:34:44 +00:00
Andrew Burgess
5209b83f53 gdb/python: missing PyObject_IsTrue error check in py-arch.c
Building on the previous two commits, I was auditing our uses of
PyObject_IsTrue looking for places where we were missing an error
check.

The gdb.Architecture.integer_type() function takes a 'signed' argument
which should be a 'bool', and the docs do say:

  If SIGNED is not specified, it defaults to 'True'.  If SIGNED is
  'False', the returned type will be unsigned.

Currently we use PyObject_IsTrue, but we are missing an error check.

To fix this I've tightened the code to enforce the bool requirement at
the point that the arguments are parsed.  With that done I can remove
the call to PyObject_IsTrue and instead compare to Py_True directly,
the object in question will always be a PyBool_Type.

However, we were testing that passing a non-bool argument for 'signed'
is treated as Py_False, this was added with this commit:

  commit 90fe61ced1
  Date:   Mon Nov 29 13:53:06 2021 +0000

      gdb/python: don't use the 'p' format for parsing args

which is when the PyObject_IsTrue call was added.  Given that the docs
do seem pretty clear that only True or False are suitable argument
values, my proposal is that we just remove these tests and instead
test that any non-bool argument value for 'signed' gives a TypeError.

This is a breaking change to the Python API, however, my hope is that
this is such a edge case that it will not cause too many problem.
I've added a NEWS entry to highlight this change though.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>
Approved-By: Tom Tromey <tom@tromey.com>
2024-11-14 19:34:43 +00:00
Andrew Burgess
d8a2c719da gdb/python: remove some additional PyObject_IsTrue calls
After the previous commit I audited all our uses of PyObject_IsTrue
looking for places where we were missing an error check.  I did find
some that are missing error checks in places where we really should
have error checks, and I'll fix those in later commits.

This commit however, focuses on those locations where PyObject_IsTrue
is called, there is no error check, and the error check isn't really
necessary because we already know that the object we are dealing with
is of type PyBool_Type.

Inline with the previous commit, in these cases I have removed the
PyObject_IsTrue call, and replaced it with a comparison against
Py_True.  In one location where it is not obvious that the object we
have is PyBool_Type I've added an assert, but in the other cases the
comparison to Py_True immediately follows a PyBool_Check call, so an
assert would be redundant.

I've added a test for the gdb.Value.format_string styling argument
being passed a non-bool value as this wasn't previously being tested,
though this new test will pass before and after this commit.

There should be no functional change after this commit.

Approved-By: Tom Tromey <tom@tromey.com>
2024-11-14 19:34:43 +00:00
Tom de Vries
5cb0406bb6 [gdb/contrib] Handle capitalized words in spellcheck.sh
The dictionary contains a few entries with capital letters:
...
$ grep -E '[A-Z]' .git/wikipedia-common-misspellings.txt | wc -l
143
...
but they don't look too interesting in the gdb context (for instance,
Habsbourg->Habsburg), so filter them out.

That leaves us with entries looking only like "foobat->foobar", so add
handling of capitalized words, such that we also rewrite "Foobat" to "Foobar".

Tested on aarch64-linux.  Verified with shellcheck.

Approved-by: Kevin Buettner <kevinb@redhat.com>
2024-11-13 22:38:19 +01:00
Tom de Vries
74b9033e6f [gdb/contrib] Add "doens't->doesn't" to common-misspellings.txt
Add "doens't->doesn't" to gdb/contrib/common-misspellings.txt, and run
gdb/contrib/spellcheck.sh to fix this in a few files.

Tested on x86_64-linux.

Approved-by: Kevin Buettner <kevinb@redhat.com>
2024-11-13 21:06:58 +01:00
Tom de Vries
ee126995f5 [gdb/contrib] Handle double quotes in spellcheck.sh
Add handling of double quotes in gdb/contrib/spellcheck.sh, and fix the
following typos:
...
inheritence -> inheritance
psuedo -> pseudo
succeded -> succeeded
...

Tested on x86_64-linux.

Approved-by: Kevin Buettner <kevinb@redhat.com>
2024-11-13 21:06:58 +01:00
Tom de Vries
0d1f7e2765 [gdb/contrib] Handle parentheses in spellcheck.sh
Currently, text adjacent to parentheses is not spell-checked:
...
$ cat tmp.txt
(upto)
$ ./gdb/contrib/spellcheck.sh tmp.txt
$
...

Add handling of parentheses, such that we get:
...
$ ./gdb/contrib/spellcheck.sh tmp.txt
upto -> up to
$
...

Rerun spellcheck.sh, resulting in a few "thru->through" replacements.

Tested on x86_64-linux.

Approved-by: Kevin Buettner <kevinb@redhat.com>
2024-11-13 21:06:58 +01:00
Bernd Edlinger
5d9887ffa2 gdb: stepping between inline functions with multiple ranges
I (Andrew) have split this small change from a larger patch which was
posted here:

  https://inbox.sourceware.org/gdb-patches/AS1PR01MB9465608EBD5D62642C51C428E4922@AS1PR01MB9465.eurprd01.prod.exchangelabs.com

And I have written the stand alone test for this issue.  The original
patch included this paragraph to explain this change (I've fixed one
typo in this text replacing 'program' with 'function'):

  ... it may happen that the infrun machinery steps from one inline
  range to another inline range of the same inline function.  That can
  look like jumping back and forth from the calling function to the
  inline function, while really the inline function just jumps from a
  hot to a cold section of the code, i.e. error handling.

The important thing that happens here is that both the outer function
and the inline function must both have multiple ranges.  When the
inferior is within the inline function and moves from one range to
another it is critical that the address we stop at is the start of a
range in both the outer function and the inline function.

The diagram below represents how the functions are split and aligned:

                           (A)       (B)
  bar:         |------------|         |---|
  foo:   |------------------|         |--------|

The inferior is stepping through 'bar' and eventually reaches
point (A) at which point control passes to point (B).

Currently, when the inferior stops, GDB notices that both 'foo' and
'bar' start at address (B), and so GDB uses the inline frame mechanism
to skip 'bar' and tells the user that the inferior is in 'foo'.

However, as we were in 'bar' before the step then it makes sense that
we should be in 'bar' after the step, and this is what the patch does.

There are two tests using the DWARF assembler, the first checks the
above situation and ensures that GDB reports 'bar' after the step.

The second test is similar, but after the step we enter a new range
where a different inline function starts, something like this:

                           (A)       (B)
  bar:         |------------|
  baz:                                |---|
  foo:   |------------------|         |--------|

In this case as we step at (A) and land at (B) we leave 'bar' and
expect to stop in 'foo', GDB shouldn't automatically enter 'baz' as
that is a completely different inline function.  And this is, indeed,
what we see.

Co-Authored-By: Andrew Burgess <aburgess@redhat.com>
2024-11-13 13:50:21 +00:00
Andrew Burgess
b9de07a5ff gdb: fix handling of DW_AT_entry_pc of inlined subroutines
The entry PC for a DIE, e.g. an inline function, might not be the base
address of the DIE.  Currently though, in block::entry_pc(), GDB
always returns the base address (low-pc or the first address of the
first range) as the entry PC.

This commit extends the block class to carry the entry PC as a
separate member variable.  Then the DWARF reader is extended to read
and set the entry PC for the block.  Now in block::entry_pc(), if the
entry PC has been set, this is the value returned.

If the entry-pc has not been set to a specific value then the old
behaviour of block::entry_pc() remains, GDB will use the block's base
address.  Not every DIE will set the entry-pc, but GDB still needs to
have an entry-pc for every block, so the existing logic supplies the
entry-pc for any block where the entry-pc was not set.

The DWARF-5 spec for reading the entry PC is a super-set of the spec
as found in DWARF-4.  For example, if there is no DW_AT_entry_pc then
DWARF-4 says to use DW_AT_low_pc while DWARF-5 says to use the base
address, which is DW_AT_low_pc or the first address in the first range
specified by DW_AT_ranges if there is no DW_AT_low_pc.

I have taken the approach of just implementing the DWARF-5 spec for
everyone.  There doesn't seem to be any benefit to deliberately
ignoring a ranges based entry PC value for DWARF-4.  If some naughty
compiler has emitted that, then lets use it.

Similarly, DWARF-4 says that DW_AT_entry_pc is an address.  DWARF-5
allows an address or a constant, where the constant is an offset from
the base address.  I allow both approaches for all DWARF versions.
There doesn't seem to be any downsides to this approach.

I ran into an issue when testing this patch where GCC would have the
DW_AT_entry_pc point to an empty range.  When GDB parses the ranges
any empty ranges are ignored.  As a consequence, the entry-pc appears
to be outside the address range of a block.

The empty range problem is certainly something that we can, and should
address, but that is not the focus of this patch, so for now I'm
ignoring that problem.  What I have done is added a check: if the
DW_AT_entry_pc is outside the range of a block then the entry-pc is
ignored, GDB will then fall-back to its default algorithm for
computing the entry-pc.

If/when in the future we address the empty range problem, these
DW_AT_entry_pc attributes will suddenly become valid and GDB will
start using them.  Until then, GDB continues to operate as it always
has.

An early version of this patch stored the entry-pc within the block
like this:

  std::optional<CORE_ADDR> m_entry_pc;

However, a concern was raised that this, on a 64-bit host, effectively
increases the size of block by 16-bytes (8-bytes for the CORE_ADDR,
and 8-bytes for the std::optional's bool plus padding).

If we remove the std::optional part and just use a CORE_ADDR then we
need to have a "special" address to indicate if m_entry_pc is in use
or not.  I don't really like using special addresses; different
targets can access different address ranges, even zero is a valid
address on some targets.

However, Bernd Edlinger suggested storing the entry-pc as an offset,
and I think that will resolve my concerns.  So, we store the entry-pc
as a signed offset from the block's base address (the first address of
the first range, or the start() address value if there are now
ranges).  Remember, ranges can be out of order, in which case the
first address of the first range might be greater than the entry-pc.

When GDB needs to read the entry-pc we can add the offset onto the
blocks base address to recalculate it.

With this done, on a 64-bit host, block only needs to increase by
8-bytes.

The inline-entry.exp test was originally contributed by Bernd here:

  https://inbox.sourceware.org/gdb-patches/AS1PR01MB94659E4D9B3F4A6006CC605FE4922@AS1PR01MB9465.eurprd01.prod.exchangelabs.com

though I have made some edits, making more use of lib/gdb.exp
functions, making the gdb_test output patterns a little tighter, and
updating the test to run with Clang.  I also moved the test to
gdb.opt/ as that seemed like a better home for it.

Co-Authored-By: Bernd Edlinger <bernd.edlinger@hotmail.de>
2024-11-13 13:41:27 +00:00
Andrew Burgess
06b8b0ad97 gdb/testsuite: some cleanups in gdb.base/annota{1,3}.exp tests
Fedora GDB has, for years, carried an out of tree patch for the
gdb.base/annota{1,3}.exp tests.  The patch simply adds a call to 'set
breakpoint pending off' near the start of each test.

Normally GDB tests are written using gdb_test or gdb_test_multiple,
with gdb_test being a wrapper around gdb_test_multiple.  Inside
gdb_test_multiple we add a test pattern which detects if GDB offers
the user an interactive yes/no prompt and immediately fails the test.

What this means is that if something goes wrong with a test like:

  gdb_test "break main" ".*"

and GDB ends up offering this prompt:

  Make breakpoint pending on future shared library load? (y or [n])

then instead of hanging waiting for the test to timeout, DejaGNU will
spot the interactive prompt and immediately fail the test.

In the gdb.base/annota{1,3}.exp tests we turn on GDB's annotation
mode, and many of the tests in these scripts are written using
send_gdb and gdb_expect or gdb_expect_list.  This is done because in
the past, gdb_test_multiple and friends were hard-coded to use the
"normal" GDB prompt, and these tests instead expect the annotated
prompt.  Specifically, gdb_test_multiple expects '$gdb_prompt $' as
the full prompt, that is the value of $gdb_prompt followed by a single
white space.  The annotation tests do update the value of $gdb_prompt,
but with annotations on there is no trailing whitespace, so
gdb_test_multiple's default behaviour doesn't work, which is why the
test scripts originally avoided using gdb_test_multiple.

As a result none of the tests in these files would early exit if we
got an interactive yes/no prompt, and instead we'd be relying on each
test to timeout, which could take a while.

However, gdb_test_multiple now accepts a -prompt argument, so we can
modify the prompt we are looking for, which is neat.

So, I started off by going through these tests an changing all of the
tests that create a breakpoint to use gdb_test, passing the -prompt
option to change the prompt.

While doing that I noticed some other things that I could improve in
these tests, I've cleaned up the use of standard_testfile, switched to
use prepare_for_testing, and removed some redundant clean_restart and
'set height 0' calls (set height 0 is done within clean_restart, which
is called by prepare_for_testing).

I've updated some comments which said "we can't use gdb_test" to say
"we can use gdb_test with -prompt option", and I've removed some
commented out debug code (e.g. setting 'exp_internal').

Finally, I ran these two tests through check-all-boards, and spotted
that annota1.exp failed when using a remote host.  This is because one
test checks for a full path to the binary in some output, and with a
remote host the binary ends up being copied and the path is not as
expected.

I'm assuming that checking the full path is important, so I've
disabled this test on remote host boards.

After all these changes I checked using 'make check-all-boards' and
there are no unexpected results on either of these tests.

Tested-By: Tom de Vries <tdevries@suse.de>
Acked-By: Tom de Vries <tdevries@suse.de>
2024-11-12 14:41:23 +00:00
Andrew Burgess
26885b2b6c gdb/testsuite: fix duplicate test names in gdb.trace/
After this commit:

  commit 35f09cd5d7
  Date:   Wed Jul 31 15:04:25 2024 +0200

      [gdb/testsuite] Detect trailing-text-in-parentheses duplicates

we are now seeing some duplicate test names in gdb.trace/ tests when
using native-gdbserver or native-extended-gdbserver boards.  This is
all due to tests that use some text in trailing parenthesis to make
the test name unique.

I've gone through and edited the test names as best I could to make
them all unique.  Hopefully the updated test names should all make
sense.

On my machine I'm no longer seeing any duplicates with either of the
boards listed above.

Acked-By: Tom de Vries <tdevries@suse.de>
2024-11-12 14:35:38 +00:00
Andrew Burgess
31fa6221bf gdb/readline: don't get stuck thinking an EOF arrived
It was brought to my attention[1] that if a user makes use of Ctrl+d
to quit from a secondary prompt (e.g. the prompt used to enter lines
for the 'commands' command) then GDB will start displaying some
unexpected blank lines.  Here's an example:

  Reading symbols from /tmp/hello.x...
  (gdb) break main
  Breakpoint 1 at 0x401198: file hello.c, line 18.
  (gdb) commands
  Type commands for breakpoint(s) 1, one per line.
  End with a line saying just "end".
  >quit			# <----------- Use Ctrl+d to quit here.
  (gdb) show architecture
			# <----------- This blank line is unexpected.
  The target architecture is set to "auto" (currently "i386:x86-64").
  (gdb)

I've marked up where I press 'Ctrl+d', and also the unexpected blank
line.

This issue will only happen if bracketed-paste-mode is in use.  If
this has been disabled (e.g. in ~/.inputrc) then this issue will not
occur.

The blank line is not just emitted for the 'show architecture'
command.  The blank line is actually caused by an extra '\n' character
emitted by readline after it has gathered a complete line of input,
and so will occur for any command.

The problem is caused by readline getting "stuck" in a state where it
thinks that an EOF has just been delivered.  This state is set when
the 'Ctrl+d' does deliver an EOF, but then this state is never fully
reset.  As a result, every time readline completes a line, it thinks
that the line was completed due to an EOF and so adds an extra '\n'
character.

Obviously the real fix for this issue is to patch readline, and I do
have a patch for that[2], however, version 8.2 of readline has been
released, and contains this issue.  As such, if GDB is linked against
the system readline, and that system readline is 8.2, then we can
expect to see this issue.

There's a pretty simple, and cheap workaround that we can add to GDB
that will mitigate this issue.

I propose that we add this workaround to GDB.  If/when the readline
patch is accepted then I'll back-port this to our local readline copy,
but retaining the workaround will be harmless, and will make GDB play
nicer with system readline libraries (version 8.2).

[1] https://inbox.sourceware.org/gdb-patches/34ef5438-8644-44cd-8537-5068e0e5e434@redhat.com
[2] https://lists.gnu.org/archive/html/bug-readline/2024-10/msg00014.html

Reviewed-By: Keith Seitz <keiths@redhat.com>
2024-11-12 14:07:35 +00:00
Andrew Burgess
b0c6153ccf gdb/readline: add readline library version to 'show configuration'
When debugging readline issues I'd like an easy way to know (for sure)
what version of readline GDB is using.  This could also be useful when
writing readline tests, knowing the precise readline version will
allow us to know if we expect a test to pass or not.

Add the readline library version to the output of the 'show
configuration' command.  Also include a suffix indicating if we are
using the system readline, or the statically linked in readline.

The information about static readline vs shared readline can be
figured out from the configure command output, but having it repeated
in the readline version line makes it super easy to grok within tests,
and it's super cheap, so I don't see this as a problem.
2024-11-12 13:58:19 +00:00
Guinevere Larsen
09c964ce90 gdb/testsuite: fix gdb.reverse/i386-avx-reverse.exp with clang
The test gdb.reverse/i386-avx-reverse.exp was changed by the recent
commit:

    commit 5bf288d5a8
    Author: Guinevere Larsen <guinevere@redhat.com>
    Date:   Fri Jul 26 17:31:14 2024 -0300

    gdb/record: support AVX instructions VMOVDQ(U|A) when recording

In that commit I added a few calls to the instruction vmovdqa to and
from memory addresses. Because my local gcc testing always had aligned
pointers, I thought this would always work, but clang (and maybe other
compilers) might not do the same, which will cause vmovdqa to segfault,
and the test to fail spectacularly.

This commit fixes that by using the pre-existing precise-aligned-alloc
to allocate the dynamic buffers, forcing them to be aligned to the
required boundary for vmovdqa instruction to work. The code was then
re-shuffled to keep the current clustering of instructions.

Approved-By: Tom Tromey <tom@tromey.com>
2024-11-12 08:48:03 -03:00
Shahab Vahedi
af3f129d92 Handle type-casting in template parameter list when hashing symbols
Due to a logical bug in gdb/cp-support.c:cp_search_name_hash(), GDB
may not be able to find a symbol when asked by the user.  See the
accompanying test for such demonstration.

The cp_search_name_hash() cannot correctly handle a (demangled) symbol
that comprises of type-casting for the first parameter in its template
parameter list, e.g.:

  foo<(enum_test)0>(int, int)

In this example, the processing logic in cp_search_name_hash() considers
the "foo<" string for hashing instead of "foo".  This is due to a faulty
logic in the processing loop that tries to _keep_ hashing if a '<' char
with the following property is encountered:

---------------------------------------------------------------------
for (const char *string = search_name; *string != '\0'; ++string)
  {
    ...

    if (*string == '(')
      break;

    ...

    /* Ignore template parameter list.  */
    if (string[0] == '<'
        && string[1] != '(' && string[1] != '<' && string[1] != '='
        && string[1] != ' ' && string[1] = '\0')
      break;

    ...
    hash = SYMBOL_HASH_NEXT (hash, *string);
  }
---------------------------------------------------------------------

Ostensibly, this logic strives to bail out of the processing loop as
soon as the beginning of an argument list is encountered, "(int, int)"
in the example, or the beginning of a template parameter list, the
"<(enum_test)0>" in the example.  However, when "string" is pointing
at '<', the following incorrect logic takes precedence:

---------------------------------------------------------------------
for (const char *string = search_name; *string != '\0'; ++string)
  {
    if (*string == '(')
      break;
    ...
    if (string[0] == '<' && string[1] != '(' ...)
      break;

    hash = SYMBOL_HASH_NEXT (hash, *string);
  }
---------------------------------------------------------------------

In "foo<(enum_test)0>(int, int)", the '(' char that is positioned after
the '<' char causes the "if" condition at the end of the loop not to
"break".  As a result, the '<' is considered for hashing and at the
beginning of the next iteration, the loop is exited because "string"
points to '(' char.

It's obvious that the intention of the "if" condition at the end of the
loop body is to handle cases where the method name is "operator<",
"operator<<", or "operator<=".  While fixing the issue, I've re-written
the logic as such to make that more explicit.  Still, the complexity of
the function remains O(n).  It is worth mentioning that in the same
file the "find_toplevel_char()" follows the same explicit logic.

Reviewed-By: Lancelot SIX <lancelot.six@amd.com>
Reviewed-By: Pedro Alves <pedro@palves.net>
Approved-by: Tom Tromey <tom@tromey.com>
Change-Id: I64cbdbe79671e070cc5da465d1cce7989c58074e
2024-11-12 00:01:55 +01:00
Andrew Burgess
df0445b370 gdb/testsuite: fix typo 'unsupport' to 'unsupported'
I noticed that in commit:

  commit 5cabc8098e
  Date:   Wed Jul 31 15:55:57 2024 +0100

      gdb/python: implement Python find_exec_by_build_id hook

I managed to typo 'unsupported' as 'unsupport'.  If you run the test
on a target that doesn't support core file creation then you'll get a
TCL error.

Fixed in this commit.
2024-11-11 16:11:18 +00:00
Andrew Burgess
f03239584d gdb/testsuite: fix failure in gdb.base/info_sources.exp
I ran into an unexpected failure in gdb.base/info_sources.exp.  The
test in question runs this command:

  (gdb) info sources -d -- -d

That is, list all the source files whose directory name matches the
regexp '-d'.  The expectation is that no source files will be listed.

Unfortunately, when I ran the test some source files are listed; the
directory I am running in contains the pattern '-d', and so the test
fails.

As we cannot control where the developer is building and testing GDB,
I propose that instead of just testing with '-d' we should search
through all the letters a-z and find one that isn't present in the
source file directory name.  I'm still including the leading '-'
character in the regexp.

So now, unless GDB is being built in a directory that contains '-a',
'-b', '-c', .... '-z', the test will find one letter which isn't
present, and use that for the test.

To avoid test names changing between runs in different directories
I've had to tweak the test name to something more generic, but there
should be no change in which parts of GDB are actually being tested.

Approved-By: Tom Tromey <tom@tromey.com>
2024-11-11 15:29:53 +00:00
Tom de Vries
7d88c8a06c [gdb/testsuite] Reduce quoting in gdb.base/annota1.exp
Reduce quoting in gdb.base/annota1.exp, mostly using string_to_regexp.

Tested on arm-linux and x86_64-linux.
2024-11-11 16:02:57 +01:00
Tom de Vries
c9353fa6e7 [gdb/testsuite] Fix gdb.base/annota1.exp on arm-linux
On arm-linux, gdb.base/annota1.exp fails:
...
PASS: gdb.base/annota1.exp: breakpoint info
run^M
^M
^Z^Zpost-prompt^M
Starting program: /home/linux/gdb/build/gdb/testsuite/outputs/gdb.base/annota1/annota1 ^M
^M
^Z^Zbreakpoints-invalid^M
^M
^Z^Zframes-invalid^M
^M
^Z^Zstarting^M
^M
^Z^Zframes-invalid^M
[Thread debugging using libthread_db enabled]^M
Using host libthread_db library "/lib/arm-linux-gnueabihf/libthread_db.so.1".^M
^M
^Z^Zbreakpoints-invalid^M
^M
^Z^Zbreakpoint 1^M
^M
Breakpoint 1, ^M
^Z^Zframe-begin 0 0x40054a^M
^M
^Z^Zframe-function-name^M
main^M
^Z^Zframe-args^M
 ()^M
^Z^Zframe-source-begin^M
 at ^M
^Z^Zframe-source-file^M
/home/linux/gdb/src/gdb/testsuite/gdb.base/annota1.c^M
^Z^Zframe-source-file-end^M
:^M
^Z^Zframe-source-line^M
15^M
^Z^Zframe-source-end^M
^M
^M
^Z^Zsource /home/linux/gdb/binutils-gdb.git/gdb/testsuite/gdb.base/annota1.c:15:103:beg:0x40054a^M
^M
^Z^Zframe-end^M
^M
^Z^Zstopped^M
^M
^Z^Zpre-prompt^M
(gdb) ^M
^Z^Zprompt^M
FAIL: gdb.base/annota1.exp: run until main breakpoint (timeout)
...
because the regexp doesn't match the first frames-invalid annotation.

Fix this by adding an optional frames-invalid annotation in the regexp.

Tested on arm-linux and x86_64-linux.
2024-11-11 16:02:57 +01:00
Tom de Vries
89e99b6747 [gdb/testsuite] Avoid intermittent failures on another debuginfod test
With test-case gdb.debuginfod/solib-with-soname.exp on aarch64-linux, I ran
into:
...
(gdb) core-file solib-with-soname.core^M
Downloading 197.86 K file libfoo_1.so...^M
[New LWP 997314]^M
[Thread debugging using libthread_db enabled]^M
Using host libthread_db library "/lib64/libthread_db.so.1".^M
Core was generated by `solib-with-soname'.^M
Program terminated with signal SIGABRT, Aborted.^M
(gdb) FAIL: $exp: load core file, use debuginfod: load core file
...

The test-case doesn't expect the "197.86 K" part.

The same problem was fixed for another test-case in commit a723c56efb
("gdb/testsuite: avoid intermittent failures on a debuginfod test").

Fix this in the same way: by updating the regexp.

Tested on aarch64-linux.

PR testsuite/32354
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=32354
2024-11-11 15:57:38 +01:00
Tom Tromey
218ee1660d Add setting to control frame language mismatch warning
A customer noted that there is no way to prevent the "current language
does not match this frame" warning.  This patch adds a new setting to
allow this warning to be suppressed.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>
Approved-By: Andrew Burgess <aburgess@redhat.com>
2024-11-11 07:42:01 -07:00
Tom Tromey
3a983e041b Re-run isort
pre-commit pointed out that one file needed a change to satisfy isort.
This patch is the result.
2024-11-11 07:22:24 -07:00
Lancelot SIX
c0a07e7d48 gdb/dwarf2/read.c: Handle empty CU name
I recently came across a case where a compiler would emit a CU with an
empty name.  In such case, the attribute object constructed by GDB will
return nullptr when as_string is called.  One place is not checking for
this possibility.  As a result, loading such binary results in a GDB
crash:

    $ gdb -q a.out
    Reading symbols from a.out...

    Fatal signal: Segmentation fault
    ----- Backtrace -----
    [...]
    0x742f4dd8afab __strcmp_avx2
            ../sysdeps/x86_64/multiarch/strcmp-avx2.S:283
    0x58593704a0bc prepare_one_comp_unit
            ../../gdb/dwarf2/read.c:21842
    0x585937053fd9 process_psymtab_comp_unit
            ../../gdb/dwarf2/read.c:4633
    0x585937053fd9 _ZN23cooked_index_debug_info11process_cusEmN9__gnu_cxx17__normal_iteratorIPSt10unique_ptrI18dwarf2_per_cu_data26dwarf2_per_cu_data_deleterESt6vectorIS5_SaIS5_EEEESA_
            ../../gdb/dwarf2/read.c:4943
    [...]
    ---------------------
    A fatal error internal to GDB has been detected, further
    debugging is not possible.  GDB will now terminate.

    This is a bug, please report it.  For instructions, see:
    <https://www.gnu.org/software/gdb/bugs/>.

    Segmentation fault (core dumped)

This seems to be a regression introduced by the following commit:

    commit 00105aa1c4
    Date:   Tue Sep 24 10:24:22 2024 +0200

        [gdb/symtab] Don't expand non-Ada CUs for info exceptions

This patch fixes this issue by checking if attr->as_string returns
nullptr.

Change-Id: I78fe7a090f0bd1045b8cb2f8d088a8d6cf57fe1c
Approved-By: Andrew Burgess <aburgess@redhat.com>
Approved-By: Tom Tromey <tom@tromey.com>
2024-11-11 09:26:15 +00:00
Andrew Burgess
5cabc8098e gdb/python: implement Python find_exec_by_build_id hook
Implement extension_language_ops::find_objfile_from_buildid within
GDB's Python API.  Doing this allows users to write Python extensions
that can help locate missing objfiles when GDB opens a core file.  A
handler might perform some project- or site-specific actions to find a
missing objfile.  Or might provide some project- or site-specific
advice to the user on how they can obtain the missing objfile.

The implementation is very similar to the approach taken in:

  commit 8f6c452b5a
  Date:   Sun Oct 15 22:48:42 2023 +0100

      gdb: implement missing debug handler hook for Python

The following new commands are added as commands implemented in
Python, this is similar to how the Python missing debug and unwinder
commands are implemented:

  info missing-objfile-handlers
  enable missing-objfile-handler LOCUS HANDLER
  disable missing-objfile-handler LOCUS HANDLER

To make use of this extension hook a user will create missing objfile
handler objects, and registers these handlers with GDB.  When GDB
opens a core file and encounters a missing objfile each handler is
called in turn until one is able to help.  Here is a minimal handler
that does nothing useful:

  import gdb
  import gdb.missing_objfile

  class MyFirstHandler(gdb.missing_objfile.MissingObjfileHandler):
      def __init__(self):
          super().__init__("my_first_handler")

      def __call__(self, pspace, build_id, filename):
          # This handler does nothing useful.
          return None

  gdb.missing_objfile.register_handler(None, MyFirstHandler())

Returning None from the __call__ method tells GDB that this handler
was unable to find the missing objfile, and GDB should ask any other
registered handlers.

Possible return values from a handler:

  - None: This means the handler couldn't help.  GDB will call other
          registered handlers to see if they can help instead.

  - False: The handler has done all it can, but the objfile couldn't
            be found.  GDB will not call any other handlers, and will
	    continue without the objfile.

  - True: The handler has installed the objfile into a location where
          GDB would normally expect to find it.  GDB should repeat its
	  normal lookup process and the objfile should now be found.

  - A string: The handler can return a filename, which is the missing
              objfile.  GDB will load this file.

Handlers can be registered globally, or per program space.  GDB checks
the handlers for the current program space first, and then all of the
global handles.  The first handler that returns a value that is not
None, has "handled" the missing objfile, at which point GDB continues.

The implementation of this feature is mostly straight forward.  I have
reworked some of the missing debug file related code so that it can be
shared with this feature.  E.g. gdb/python/lib/gdb/missing_files.py is
mostly content moved from gdb/python/lib/gdb/missing_debug.py, but
updated to be more generic.  Now gdb/python/lib/gdb/missing_debug.py
and the new file gdb/python/lib/gdb/missing_objfile.py both call into
the missing_files.py file.

For gdb/python/lib/gdb/command/missing_files.py this is even more
extreme, gdb/python/lib/gdb/command/missing_debug.py is completely
gone now and gdb/python/lib/gdb/command/missing_files.py provides all
of the new commands in a generic way.

I have made one change to the existing Python API, I renamed the
attribute Progspace.missing_debug_handlers to
Progspace.missing_file_handlers.  I don't see this as too
problematic.  This attribute was only used to implement the missing
debug feature and was never documented beyond the fact that it
existed.  There was no reason for users to be touching this attribute.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>
2024-11-10 10:18:23 +00:00
Andrew Burgess
73d7312ff6 gdb: use mapped file information to improve debuginfod text
When opening a core-file GDB is able to use debuginfod to download the
executable that matches the core-file if GDB can find a build-id for
the executable in the core-file.

In this case GDB calls debuginfod_exec_query to download the
executable and GDB prints a message like:

  Downloading executable for /path/to/core-file...

which makes sense in that case.

For a long time GDB has also had the ability to download memory-mapped
files and shared libraries when opening a core-file.  However, recent
commits have made these cases more likely to trigger, which is a good
thing, but the messaging from GDB in these cases is not ideal.  When
downloading a memory-mapped file GDB prints:

  Downloading executable for /path/to/memory-mapped-file

And for a shared library:

  Downloading executable for /path/to/libfoo.so

These last two messages could, I think, be improved.

I propose making two changes.  First, I suggest instead of using
/path/to/core-file in the first case, we use the name of the
executable that GDB is fetching.  This makes the messaging consistent
in that we print the name of the file we're fetching rather than the
name of the file we're fetching something for.

I further propose that we replace 'executable for' with the more
generic word 'file'.  The messages will then become:

  Downloading file /path/to/exec-file...
  Downloading file /path/to/memory-mapped-file...
  Downloading file /path/to/libfoo.so...

I think these messages are clearer than what we used to have, and they
are consistent in that we name the thing being downloaded in all
cases.

There is one tiny problem.  The first case relies on GDB knowing the
name of the executable it wants to download.  The only place we can
currently get that from is, I think, the memory-mapped file list.

[ ASIDE: There is `bfd_core_file_failing_command` which reports the
  executable and argument list from the core file, but this
  information is not ideal for this task.  First, the executable and
  arguments are merged into a single string, and second, the string is
  a relatively short, fixed length string, so the executable name is
  often truncated.  For these reasons I don't consider fetching the
  executable name using this bfd function as a solution. ]

We do have to consider the case that the core file does not have any
mapped file information.  This shouldn't ever be the case for a Linux
target, but it's worth considering.

[ ASIDE: I mention Linux specifically because this only becomes a
  problem if we try to do a lookup via debuginfod, which requires that
  we have build-ids available.  Linux has special support for
  embedding build-ids into the core file, but I'm not sure if other
  kernels do this. ]

For the unlikely edge case of a core-file that has build-ids, but
doesn't have any mapped file information then I propose that we
synthesis a filename like: 'with build-id xxxxxx'.  We would then see
a message like:

  Downloading file with build-id xxxxxx...

Where 'xxxxxx' would be replaced by the actual build-id.

This isn't ideal, but I think is good enough, and, as I said, I think
this case is not going to be hit very often, or maybe at all.

We already had some tests that emitted two of the above messages,
which I've updated, these cover the mapped-file and shared library
case.

The message about downloading the exec for the core-file is actually
really hard to trigger now as usually the exec will also appear in the
memory-mapped file list and GDB will download the file at this stage.
Then when GDB needs the executable for loading the symbols it'll ask
debuginfod, and debuginfod will find the file in its cache, and so no
message will be printed.

If anyone has any ideas about how to trigger this case then I'm happy
to add additional tests.

Approved-By: Tom Tromey <tom@tromey.com>
2024-11-10 10:18:22 +00:00
Alexandra Hájková
21dc8b8d28 Add dw2-aranges.exp
This test checks that GDB is able to load DWARF information when
.debug_aranges has a section address size that is set to 0.

This test was originally written by Jan Kratochvil to test commit
927aa2e778 from 2017, titled "DWARF-5: .debug_names index consumer".

This test was originally written using a static .S file and has
been present in the Fedora tree for a long time.

If dwarf2/aranges.c is modified to turn off the address_size check,
GDB will crash with SIGFPE when loading the executable with address
size set to zero.

I modified the DWARF assembler to make it possible to set the address
size to zero in a .debug_aranges section and used the DWARF assembler
to produce the assembly file.

Co-Authored-By: Jan Kratochvil <jan.kratochvil@redhat.com>
Approved-by: Kevin Buettner <kevinb@redhat.com>
2024-11-08 22:15:50 +01:00
Andrew Burgess
dbca1bef47 gdb/testsuite: fix gdb.base/basic-edit-cmd.exp test
In the recent commit:

  commit 31ada87f91
  Date:   Wed Nov 6 22:18:55 2024 +0000

      gdb: fixes and tests for the 'edit' command

the new gdb.base/basic-edit-cmd.exp was added.  The Linaro CI
highlighted an issue with the test which I failed to address before
pushing the above commit.

Part of the test loads a file into GDB and then uses the 'edit'
command with no arguments to edit the default location.  This default
location is expected to be the 'main' function.

On my local machine the line reported is the opening '{' of main, and
that is what the test checks for.

The Linaro CI though appears to see the first code line of main.

I think either result is fine as far as this test is concerned, so
I've expanded the test regexp to check for either line number.  This
should make the CI testing happy again.
2024-11-08 11:19:33 +00:00
Andrew Burgess
31ada87f91 gdb: fixes and tests for the 'edit' command
This commit was inspired by this mailing list post:

  https://inbox.sourceware.org/gdb-patches/osmtfvf5xe3yx4n7oirukidym4cik7lehhy4re5mxpset2qgwt@6qlboxhqiwgm

When reviewing that patch, the first thing I wanted to do was add some
tests for the 'edit' command because, as far as I can tell, there are
no real tests right now.

The approach I've taken for testing is to override the EDITOR
environment variable, setting this to just 'echo'.  Now when the
'edit' command is run, instead of entering an interactive editor, the
shell instead echos back the arguments that GDB is trying to pass to
the editor.  The output might look like this:

  (gdb) edit
  +22 /tmp/gdb/testsuite/gdb.base/edit-cmd.c
  (gdb)

We can then test this like any other normal command.  I then wrote
some basic tests covering a few situations like, using 'edit' before
the inferior is started.  Using 'edit' without any arguments, and
using 'edit' with a line number argument.

There are plenty of cases that are still not tested, for example, the
test program only has a single source file for example.  But we can
always add more tests later.

I then used these tests to validate the fix proposed in the above
patch.

The patch above does indeed fix some cases, specifically, when GDB
stops at a location (e.g. a breakpoint location) and then the 'edit'
command without any arguments is fixed.  But using the 'list' command
to show some other location, and then 'edit' to edit the just listed
location broken before and after the above patch.

I am instead proposing this alternative patch which I think fixes more
cases.  When GDB stops at a location then 'edit' with no arguments
should correctly edit the current line.  And using 'list XX' to list a
specific location, followed by 'edit' should also now edit the just
listed location.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=17669

Co-Authored-By: Lluís Batlle i Rossell <viric@viric.name>
Approved-By: Tom Tromey <tom@tromey.com>
2024-11-08 10:44:43 +00:00
Andrew Burgess
3105b46ed1 gdb: add filename option support
This commit adds support for filename options to GDB's option
sub-system (see cli/cli-option.{c,h}).

The new filename options support quoted and escaped filenames, and tab
completion is fully supported.

This commit adds the new option, and adds these options to the
'maintenance test-options' command as '-filename', along with some
tests that exercise this new option.

I've split the -filename testing into two.  In gdb.base/options.exp we
use the -filename option with some arbitrary strings.  This tests that
GDB can correctly extract the value from a filename option, and that
GDB can complete other options after a filename option.  However,
these tests don't actually pass real filenames, nor do they test
filename completion.

In gdb.base/filename-completion.exp I have added some tests that test
the -filename option with real filenames, and exercise filename tab
completion.

This commit doesn't include any real uses of the new filename options,
that will come in the next commit.
2024-11-04 15:56:01 +00:00
Andrew Burgess
91f8973ba3 gdb/testsuite: spring clean the gdb.stabs/gdb11479.exp test
I had reason to look at the gdb.stabs/gdb11479.exp test script and
figured it could do with a small clean up.  I've:

  - Made use of standard_testfile and the variables it defines.

  - Made use of with_test_prefix and removed the prefix from the end
    of each test name.

  - Avoid overwriting the test binary when we recompile, instead use a
    different name for each recompilation.

  - Add '.' at the end of each comment.

There should be no changes in what is tested with this commit.

Reviewed-By: Keith Seitz <keiths@redhat.com>
2024-11-04 15:51:40 +00:00
Tom Tromey
76367d2314 Add gdb.events.tui_enabled
This adds a new event source so that Python scripts can track whether
or not the TUI is presently enabled.

v2 of the patch renames "status" -> "enabled".

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=32162
Reviewed-By: Eli Zaretskii <eliz@gnu.org>
Reviewed-by: Keith Seitz <keiths@redhat.com>
2024-11-01 11:06:47 -06:00
Tom de Vries
51527eb809 [gdb/testsuite] Add read1 and readmore to make-check-all.sh
There are two useful ways to run a test-case, that are not represented by a
board file in gdb/testsuite/boards: check-read1 and check-readmore.

Consequently, they're not run either by make-check-all.sh.

Fix this by adding check-read1 and check-readmore to make-check-all.sh.

Tested on x86_64-linux.  Verified with shellcheck.

Approved-By: Andrew Burgess <aburgess@redhat.com>
2024-10-29 12:59:44 +01:00
Tom de Vries
80ac478511 [gdb/symtab] Handle multiple .debug_info sections
When compiling dw2-multiple-debug-info.c using -gdwarf-5
-fdebug-types-section, we end with two .debug_info sections in the object
file:
...
$ g++ gdb.dwarf2/dw2-multiple-debug-info.c -c -g \
    -gdwarf-5 \
    -fdebug-types-section
$ readelf -WS dw2-multiple-debug-info.o | grep -v RELA | grep .debug_info
  [10] .debug_info  PROGBITS        0 000128 0000cd 00  GC  0   0  8
  [12] .debug_info  PROGBITS        0 0001f8 0000ad 00   C  0   0  8
...

One of them contains the CU for dw2-multiple-debug-info.c, the other contains
the TU for the type of variable a.

When trying to print the type of variable a, we get:
...
$ gdb -q -batch dw2-multiple-debug-info.o -ex "ptype a"
'a' has unknown type; cast it to its declared type
...
because the TU hasn't been read.

Fix this by adding support for reading multiple .debug_info sections, similar
to how that is done for multiple .debug_types sections, getting us instead:
...
$ gdb -q -batch dw2-multiple-debug-info.o -ex "ptype a"
type = class sp1::A {
  ...
}
...

Tested on x86_64-linux.

PR symtab/32223
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=32223
2024-10-29 10:08:04 +01:00
Ijaz, Abdul B
b0fdcd4706 fortran: Fix arrays of variable length strings for FORTRAN
Before this change resolve_dynamic_array_or_string was called for
all TYPE_CODE_ARRAY and TYPE_CODE_STRING types, but, in the end,
this function always called create_array_type_with_stride, which
creates a TYPE_CODE_ARRAY type.

Suppose we have

subroutine vla_array (arr1, arr2)
  character (len=*):: arr1 (:)
  character (len=5):: arr2 (:)

  print *, arr1 ! break-here
  print *, arr2
end subroutine vla_array

The "print arr1" and "print arr2" command at the "break-here" line
gives the following output:

(gdb) print arr1
$1 = <incomplete type>
(gdb) print arr2
$2 = ('abcde', 'abcde', 'abcde')
(gdb) ptype arr1
type = Type
End Type
(gdb) ptype arr2
type = character*5 (3)

Dwarf info using Intel® Fortran Compiler for such case contains following:
 <1><fd>: Abbrev Number: 12 (DW_TAG_string_type)
    <fe>   DW_AT_name        : (indirect string, offset: 0xd2): .str.ARR1
    <102>   DW_AT_string_length: 3 byte block: 97 23 8 (DW_OP_push_object_address; DW_OP_plus_uconst: 8)

After this change resolve_dynamic_array_or_string now calls
create_array_type_with_stride or create_string_type, so if the
incoming dynamic type is a TYPE_CODE_STRING then we'll get back a
TYPE_CODE_STRING type.  Now gdb shows following:

(gdb) p arr1
$1 = ('abddefghij', 'abddefghij', 'abddefghij', 'abddefghij', 'abddefghij')
(gdb) p arr2
$2 = ('abcde', 'abcde', 'abcde')
(gdb) ptype arr1
type = character*10 (5)
(gdb) ptype arr2
type = character*5 (3)

In case of GFortran, compiler emits DW_TAG_structure_type for string type
arguments of the subroutine and it has only DW_AT_declaration tag.  This
results in <incomplete type> in gdb.  So, following issue is raised in gcc
bugzilla "https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101826".

Fixing above issue introduce regression in gdb.fortran/mixed-lang-stack.exp,
i.e. the test forces the language to C/C++ and print a Fortran string value.
The string value is a dynamic type with code TYPE_CODE_STRING.

Before this commit the dynamic type resolution would always convert this to
a TYPE_CODE_ARRAY of characters, which the C value printing could handle.

But now after this commit we get a TYPE_CODE_STRING, which
neither the C value printing, or the generic value printing code can
support.  And so, I've added support for TYPE_CODE_STRING to the generic
value printing, all characters of strings are printed together till the
first null character.

Lastly, in gdb.opt/fortran-string.exp and gdb.fortran/string-types.exp
tests it expects type of character array in 'character (3)' format but now
after this change we get 'character*3', so tests are updated accordingly.

Approved-By: Tom Tromey <tom@tromey.com>
2024-10-29 09:28:41 +01:00