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
This patch changes block::get_using to return an iterator range. This
seemed cleaner to me than the current approach of returning a pointer
to the first using directive; all the callers actually use this to
iterate.
This changes demangle_component objects to be stored on the obstack
that is part of demangle_info. It also arranges for a demangle_info
object to be kept alive by cp_merge_demangle_parse_infos. This way,
other data on the obstack can be kept while an "outer" demangle_info
needs it.
Acked-By: John Baldwin <jhb@FreeBSD.org>
Most files including gdbcmd.h currently rely on it to access things
actually declared in cli/cli-cmds.h (setlist, showlist, etc). To make
things easy, replace all includes of gdbcmd.h with includes of
cli/cli-cmds.h. This might lead to some unused includes of
cli/cli-cmds.h, but it's harmless, and much faster than going through
the 170 or so files by hand.
Change-Id: I11f884d4d616c12c05f395c98bbc2892950fb00f
Approved-By: Tom Tromey <tom@tromey.com>
A few spots (mostly in the parsers) use alloca to ensure that a string
is terminated before passing it to a printf-like function (mostly
'error'). However, this isn't needed as the "%.*s" format can be used
instead.
This patch makes this change.
In one spot the alloca is dead code and is simply removed.
Regression tested on x86-64 Fedora 38.
Approved-By: John Baldwin <jhb@FreeBSD.org>
Now that defs.h, server.h and common-defs.h are included via the
`-include` option, it is no longer necessary for source files to include
them. Remove all the inclusions of these files I could find. Update
the generation scripts where relevant.
Change-Id: Ia026cff269c1b7ae7386dd3619bc9bb6a5332837
Approved-By: Pedro Alves <pedro@palves.net>
This changes cp_lookup_rtti_type to only search for types -- not
functions or variables. Due to the symbol-matching hack, this could
just use SEARCH_TYPE_DOMAIN, but I think it's better to be clear; also
I hold on to some hope that perhaps the hack can someday be removed.
This changes lookup_symbol and associated APIs to accept
domain_search_flags rather than a domain_enum.
Note that this introduces some new constants to Python and Guile. I
chose to break out the documentation patch for this, because the
internals here do not change until a later patch, and it seemed
simpler to patch the docs just once, rather than twice.
This commit is the result of the following actions:
- Running gdb/copyright.py to update all of the copyright headers to
include 2024,
- Manually updating a few files the copyright.py script told me to
update, these files had copyright headers embedded within the
file,
- Regenerating gdbsupport/Makefile.in to refresh it's copyright
date,
- Using grep to find other files that still mentioned 2023. If
these files were updated last year from 2022 to 2023 then I've
updated them this year to 2024.
I'm sure I've probably missed some dates. Feel free to fix them up as
you spot them.
This changes gdb to use the C++17 [[fallthrough]] attribute rather
than special comments.
This was mostly done by script, but I neglected a few spellings and so
also fixed it up by hand.
I suspect this fixes the bug mentioned below, by switching to a
standard approach that, presumably, clang supports.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=23159
Approved-By: John Baldwin <jhb@FreeBSD.org>
Approved-By: Luis Machado <luis.machado@arm.com>
Approved-By: Pedro Alves <pedro@palves.net>
Initializers in lambda captures were introduced in C++14, and
conditionally used in gdb/cp-support.c and gdb/dwarf2/cooked-index.c.
Since C++17 is now required by GDB, use this feature unconditionally.
Change-Id: I87a3d567941e5c71217538fa75c952e4d421fa1d
Approved-By: Tom Tromey <tom@tromey.com>
Approved-By: Pedro Alves <pedro@palves.net>
gdb::make_unique is a wrapper around std::make_unique when compiled with
C++17. Now that C++17 is required, use std::make_unique directly in the
codebase, and remove gdb::make_unique.
Change-Id: I80b615e46e4b7c097f09d78e579a9bdce00254ab
Approved-By: Tom Tromey <tom@tromey.com>
Approved-By: Pedro Alves <pedro@palves.net
This function is just a wrapper around the current inferior's gdbarch.
I find that having that wrapper just obscures where the arch is coming
from, and that it's often used as "I don't know which arch to use so
I'll use this magical target_gdbarch function that gets me an arch" when
the arch should in fact come from something in the context (a thread,
objfile, symbol, etc). I think that removing it and inlining
`current_inferior ()->arch ()` everywhere will make it a bit clearer
where that arch comes from and will trigger people into reflecting
whether this is the right place to get the arch or not.
Change-Id: I79f14b4e4934c88f91ca3a3155f5fc3ea2fadf6b
Reviewed-By: John Baldwin <jhb@FreeBSD.org>
Approved-By: Andrew Burgess <aburgess@redhat.com>
While GDB is still C++11, lets add a gdb::make_unique template
function that can be used to create std::unique_ptr objects, just like
the C++14 std::make_unique.
If GDB is being compiled with a C++14 compiler then the new
gdb::make_unique function will delegate to the std::make_unique. I
checked with gcc, and at -O1 and above gdb::make_unique will be
optimised away completely in this case.
If C++14 (or later) becomes our minimum, then it will be easy enough
to go through the code and replace gdb::make_unique with
std::make_unique later on.
I've make use of this function in all the places I think this can
easily be used, though I'm sure I've probably missed some.
Should be no user visible changes after this commit.
Approved-By: Tom Tromey <tom@tromey.com>
Use move capture in gdb_demangle when compiling for c++14 or higher, to save a
std::string copy.
Tested on x86_64-linux.
Reported-By: Tom Tromey <tom@tromey.com>
Approved-By: Tom Tromey <tom@tromey.com>
Latest libc++[1] causes transitive include to <locale> when
<mutex> or <thread> header is included. This causes
gdb to not build[2] since <locale> defines isupper/islower etc.
functions that are explicitly macroed-out in safe-ctype.h to
prevent their use.
Use the suggestion from libc++ to include <locale> internally when
building in C++ mode to avoid build errors.
Use safe-gdb-ctype.h as the include instead of "safe-ctype.h"
to keep this isolated to gdb since rest of binutils
does not seem to use much C++.
[1]: https://reviews.llvm.org/D144331
[2]: https://issuetracker.google.com/issues/277967395
In some cases GDB will fail when attempting to complete a command that
involves a rust symbol, the failure can manifest as a crash.
The problem is caused by the completion_match_for_lcd object being
left containing invalid data during calls to cp_symbol_name_matches_1.
The first question to address is why we are calling a C++ support
function when handling a rust symbol. That's due to GDB's auto
language detection for msymbols, in some cases GDB can't tell if a
symbol is a rust symbol, or a C++ symbol.
The test application contains symbols for functions which are
statically linked in from various rust support libraries. There's no
DWARF for these symbols, so all GDB has is the msymbols built from the
ELF symbol table.
Here's the problematic symbol that leads to our crash:
mangled: _ZN4core3str21_$LT$impl$u20$str$GT$5parse17h5111d2d6a50d22bdE
demangled: core::str::<impl str>::parse
As an msymbol this is initially created with language auto, then GDB
eventually calls symbol_find_demangled_name, which loops over all
languages calling language_defn::sniff_from_mangled_name, the first
language that can demangle the symbol gets assigned as the language
for that symbol.
Unfortunately, there's overlap in the mangled symbol names,
some (legacy) rust symbols can be demangled as both rust and C++, see
cplus_demangle in libiberty/cplus-dem.c where this is mentioned.
And so, because we check the C++ language before we check for rust,
then the msymbol is (incorrectly) given the C++ language.
Now it's true that is some cases we might be able to figure out that a
demangled symbol is not actually a valid C++ symbol, for example, in
our case, the construct '::<impl str>::' is not, I believe, valid in a
C++ symbol, we could look for ':<' and '>:' and refuse to accept this
as a C++ symbol.
However, I'm not sure it is always possible to tell that a demangled
symbol is rust or C++, so, I think, we have to accept that some times
we will get this language detection wrong.
If we accept that we can't fix the symbol language detection 100% of
the time, then we should make sure that GDB doesn't crash when it gets
the language wrong, that is what this commit addresses.
In our test case the user tries to complete a symbol name like this:
(gdb) complete break pars
This results in GDB trying to find all symbols that match 'pars',
eventually we consider our problematic symbol, and we end up with a
call stack that looks like this:
#0 0x0000000000f3c6bd in strncmp_iw_with_mode
#1 0x0000000000706d8d in cp_symbol_name_matches_1
#2 0x0000000000706fa4 in cp_symbol_name_matches
#3 0x0000000000df3c45 in compare_symbol_name
#4 0x0000000000df3c91 in completion_list_add_name
#5 0x0000000000df3f1d in completion_list_add_msymbol
#6 0x0000000000df4c94 in default_collect_symbol_completion_matches_break_on
#7 0x0000000000658c08 in language_defn::collect_symbol_completion_matches
#8 0x0000000000df54c9 in collect_symbol_completion_matches
#9 0x00000000009d98fb in linespec_complete_function
#10 0x00000000009d99f0 in complete_linespec_component
#11 0x00000000009da200 in linespec_complete
#12 0x00000000006e4132 in complete_address_and_linespec_locations
#13 0x00000000006e4ac3 in location_completer
In cp_symbol_name_matches_1 we enter a loop, this loop repeatedly
tries to match the demangled problematic symbol name against the user
supplied text ('pars'). Each time around the loop another component
of the symbol name is stripped off, thus, we check 'pars' against
these options:
core::str::<impl str>::parse
str::<impl str>::parse
<impl str>::parse
parse
As soon as we get a match the cp_symbol_name_matches_1 exits its loop
and returns. In our case, when we're looking for 'pars', the match
occurs on the last iteration of the loop, when we are comparing to
'parse'.
Now the problem here is that cp_symbol_name_matches_1 uses the
strncmp_iw_with_mode, and inside strncmp_iw_with_mode we allow for
skipping over template parameters. This allows GDB to match the
symbol name 'foo<int>(int,int)' if the user supplies 'foo(int,'.
Inside strncmp_iw_with_mode GDB will record any template arguments
that it has skipped over inside the completion_match_for_lcd object
that is passed in as an argument.
And so, when GDB tries to match against '<impl str>::parse', the first
thing it sees is '<impl str>', GDB assumes this is a template argument
and records this as a skipped region within the
completion_match_for_lcd object. After '<impl str>' GDB sees a ':'
character, which doesn't match with the 'pars' the user supplied, so
strncmp_iw_with_mode returns a value indicating a non-match. GDB then
removes the '<impl str>' component from the symbol name and tries
again, this time comparing to 'parse', which does match.
Having found a match, then in cp_symbol_name_matches_1 we record the
match string, and the full symbol name within the
completion_match_result object, and return.
The problem here is that the skipped region, the '<impl str>' that we
recorded in the penultimate loop iteration was never discarded, its
still there in our returned result.
If we look at what the pointers held in the completion_match_result
that cp_symbol_name_matches_1 returns, this is what we see:
core::str::<impl str>::parse
| \________/ |
| | '--- completion match string
| '---skip range
'--- full symbol name
When GDB calls completion_match_for_lcd::finish, GDB tries to create a
string using the completion match string (parse), but excluding the
skip range, as the stored skip range is before the start of the
completion match string, then GDB tries to do some weird string
creation, which will cause GDB to crash.
The reason we don't often see this problem in C++ is that for C++
symbols there is always some non-template text before the template
argument. This non-template text means GDB is likely to either match
the symbol, or reject the symbol without storing a skip range.
However, notice, I did say, we don't often see this problem. Once I
understood the issue, I was able to reproduce the crash using a pure
C++ example:
template<typename S>
struct foo
{
template<typename T>
foo (int p1, T a)
{
s = 0;
}
S s;
};
int
main ()
{
foo<int> obj (2.3, 0);
return 0;
}
Then in GDB:
(gdb) complete break foo(int
The problem here is that the C++ symbol for the constructor looks like
this:
foo<int>::foo<double>(int, double)
When GDB enters cp_symbol_name_matches_1 the symbols it examines are:
foo<int>::foo<double>(int, double)
foo<double>(int, double)
The first iteration of the loop will match the 'foo', then add the
'<int>' template argument will be added as a skip range. When GDB
find the ':' after the '<int>' the first iteration of the loop fails
to match, GDB removes the 'foo<int>::' component, and starts the
second iteration of the loop.
Again, GDB matches the 'foo', and now adds '<double>' as a skip
region. After that the '(int' successfully matches, and so the second
iteration of the loop succeeds, but, once again we left the '<int>' in
place as a skip region, even though this occurs before the start of
our match string, and this will cause GDB to crash.
This problem was reported to the mailing list, and a solution
discussed in this thread:
https://sourceware.org/pipermail/gdb-patches/2023-January/195166.html
The solution proposed here is similar to one proposed by the original
bug reported, but implemented in a different location within GDB.
Instead of placing the fix in strncmp_iw_with_mode, I place the fix in
cp_symbol_name_matches_1. I believe this is a better location as it
is this function that implements the loop, and it is this loop, which
repeatedly calls strncmp_iw_with_mode, that should be resetting the
result object state (I believe).
What I have done is add an assert to strncmp_iw_with_mode that the
incoming result object is empty.
I've also added some other asserts in related code, in
completion_match_for_lcd::mark_ignored_range, I make some basic
assertions about the incoming range pointers, and in
completion_match_for_lcd::finish I also make some assertions about how
the skip ranges relate to the match pointer.
There's two new tests. The original rust example that was used in the
initial bug report, and a C++ test. The rust example depends on which
symbols are pulled in from the rust libraries, so it is possible that,
at some future date, the problematic symbol will disappear from this
test program. The C++ test should be more reliable, as this only
depends on symbols from within the C++ source code.
Since I originally posted this patch to the mailing list, the
following patch has been merged:
commit 6e7eef7216
Date: Sun Mar 19 09:13:10 2023 -0600
Use rust_demangle to fix a crash
This solves the problem of a rust symbol ending up in the C++ specific
code by changing the order languages are sorted. However, this new
commit doesn't address the issue in the C++ code which was fixed with
this commit.
Given that the C++ issue is real, and has a reproducer, I'm still
going to merge this fix. I've left the discussion of rust in this
commit message as I originally wrote it, but it should be read within
the context of GDB prior to commit 6e7eef7216.
Co-Authored-By: Zheng Zhan <zzlossdev@163.com>
This converts block_static_block and block_global_block to be methods.
This was mostly written by script. It was simpler to convert them at
the same time because they're often used near each other.
This converts block_scope, block_set_scope, block_using, and
block_set_using to be methods. These are all done at once to make it
easier to also convert block_initialize_namespace at the same time.
This was mostly written by script.
This helps resolve some cyclic include problem later in the series.
The only language-related thing frame.h needs is enum language, and that
is in defs.h.
Doing so reveals that a bunch of files were relying on frame.h to
include language.h, so fix the fallouts here and there.
Change-Id: I178a7efec1953c2d088adb58483bade1f349b705
Reviewed-By: Bruno Larsen <blarsen@redhat.com>
This commit is the result of running the gdb/copyright.py script,
which automated the update of the copyright year range for all
source files managed by the GDB project to be updated to include
year 2023.
Iterate over objfiles in search order using the objfile of the selected
block as current_objfile so the iteration can stay inside the block's
linker namespace.
If you try to set a breakpoint at a function such as "b
f(std::string)", and the current language is C, the breakpoint fails
to be set, like so:
(gdb) set language c
break f(std::string)
Function "f(std::string)" not defined.
Make breakpoint pending on future shared library load? (y or [n]) n
(gdb)
The problem is that the code in GDB that expands the std::string
typedef hits this in c-typeprint.c:
/* If we have "typedef struct foo {. . .} bar;" do we want to
print it as "struct foo" or as "bar"? Pick the latter for
C++, because C++ folk tend to expect things like "class5
*foo" rather than "struct class5 *foo". We rather
arbitrarily choose to make language_minimal work in a C-like
way. */
if (language == language_c || language == language_minimal)
{
if (type->code () == TYPE_CODE_UNION)
gdb_printf (stream, "union ");
else if (type->code () == TYPE_CODE_STRUCT)
{
if (type->is_declared_class ())
gdb_printf (stream, "class ");
else
gdb_printf (stream, "struct ");
}
else if (type->code () == TYPE_CODE_ENUM)
gdb_printf (stream, "enum ");
}
I.e., std::string is expanded to "class std::..." instead of just
"std::...", and then the "f(class std::..." symbol doesn't exist.
Fix this by making cp-support.c:inspect_type print the expanded
typedef type using the language of the symbol whose type we're
expanding the typedefs for -- in the example in question, the
"std::string" typedef symbol, which is a C++ symbol.
Use type_print_raw_options as it seems to me that in this scenario we
always want raw types, to match the real symbol names.
Adjust the gdb.cp/break-f-std-string.exp testcase to try setting a
breakpoint at "f(std::string)" in both C and C++.
Change-Id: Ib54fab4cf0fd307bfd55bf1dd5056830096a653b
Currently, on any remotely modern GNU/Linux system,
gdb.cp/no-dmgl-verbose.exp fails like so:
break 'f(std::string)'
Function "f(std::string)" not defined.
(gdb) FAIL: gdb.cp/no-dmgl-verbose.exp: gdb_breakpoint: set breakpoint at 'f(std::string)'
break 'f(std::basic_string<char, std::char_traits<char>, std::allocator<char> >)'
Function "f(std::basic_string<char, std::char_traits<char>, std::allocator<char> >)" not defined.
(gdb) PASS: gdb.cp/no-dmgl-verbose.exp: DMGL_VERBOSE-demangled f(std::string) is not defined
This testcase was added back in 2011, here:
[patch] Remove DMGL_VERBOSE
https://sourceware.org/pipermail/gdb-patches/2011-June/083081.html
Back then, the testcase would pass cleanly. It turns out that the
reason it fails today is that the testcase is exercising something in
GDB that only makes sense if the program is built for the pre-C++11
libstc++ ABI. Back then the C++11 ABI didn't exist yet, but nowadays,
you need to compile with -D_GLIBCXX_USE_CXX11_ABI=0 to use the old
ABI. See "Dual ABI" in the libstdc++ manual, at
<https://gcc.gnu.org/onlinedocs/libstdc++/manual/using_dual_abi.html>.
If we tweak the gdb.cp/no-dmgl-verbose.exp testcase to force the old
ABI with -D_GLIBCXX_USE_CXX11_ABI=0, then it passes cleanly.
So why is it that setting a breakpoint at "f(std::string)" fails with
modern ABI, but passes with old ABI?
This is where libiberty demangler's DMGL_VERBOSE option comes in. The
Itanium ABI mangling scheme has a shorthand form for std::string (and
some other types). See
<https://itanium-cxx-abi.github.io/cxx-abi/abi.html>:
"In addition, the following catalog of abbreviations of the form "Sx" are used:
<substitution> ::= St # ::std::
<substitution> ::= Sa # ::std::allocator
<substitution> ::= Sb # ::std::basic_string
<substitution> ::= Ss # ::std::basic_string < char,
::std::char_traits<char>,
::std::allocator<char> >
<substitution> ::= Si # ::std::basic_istream<char, std::char_traits<char> >
<substitution> ::= So # ::std::basic_ostream<char, std::char_traits<char> >
<substitution> ::= Sd # ::std::basic_iostream<char, std::char_traits<char> >
"
When the libiberty demangler encounters such a abbreviation, by
default, it expands it to the user-friendly typedef "std::string",
"std::iostream", etc.. If OTOH DMGL_VERBOSE is specified, the
abbreviation is expanded to the underlying, non-typedefed fullname
"std::basic_string<char, std::char_traits<char>, std::allocator<char> >"
etc. as documented in the Itanium ABI, and pasted above. You can see
the standard abbreviations/substitutions in
libiberty/cp-demangle.c:standard_subs.
Back before Jan's patch in 2011, there were parts of GDB that used
DMGL_VERBOSE, and others that did not, leading to mismatches. The
solution back then was to stop using DMGL_VERBOSE throughout.
GDB has code in place to let users set a breakpoint at a function with
typedefs in its parameters, like "b f(uint32_t)". Demangled function
names as they appear in the symbol tables almost (more on this is in a
bit) never have typedefs in them, so when processing "b f(uint32_t)"
GDB first replaces "uint32_t" for its underlying type, and then sets a
breakpoint on the resulting prototype, in this case "f(unsigned int)".
Now, if DMGL_VERBOSE is _not_ used, then the demangler demangles the
mangled name of a function such as "void f(std::string)" that was
mangled using the standard abbreviations mentioned above really as:
"void f(std::string)".
For example, the mangled name of "void f(std::string)" if you compile
with old pre-C++11 ABI is "_Z1fSs". That uses the abbreviation "Ss",
so if you demangle that without DMGL_VERBOSE, you get:
$ echo "_Z1fSs" | c++filt --no-verbose
f(std::string)
while with DMGL_VERBOSE you'd get:
$ echo "_Z1fSs" | c++filt
f(std::basic_string<char, std::char_traits<char>, std::allocator<char> >)
If, when the user sets a breakpoint at "f(std::string)", GDB would
replace the std::string typedef for its underlying type using the same
mechanism I mentioned for the "f(uint32_t)" example above, then GDB
would really try to set a breakpoint at "f(std::basic_string<char,
std::char_traits<char>, std::allocator<char> >)", and that would fail,
as the function symbol GDB knows about for that function, given no
DMGL_VERBOSE, is "f(std::string)".
For this reason, the code that expands typedefs in function parameter
names has an exception for std::string (and other standard
abbreviation types), such that "std::string" is never
typedef-expanded.
And here lies the problem when you try to do "b f(std::string)" with a
program compiled with the C++11 ABI. In that case, std::string
expands to a different underlying type, like so:
f(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >)
and this symbol naturally mangles differently, as:
_Z1fNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE
and then because this doesn't use the shorthand mangling abbreviation
for "std::string" anymore, it always demangles as:
f(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >)
Now, when using the C++11 ABI, and you set a breakpoint at
"f(std::string)", GDB's typedefs-in-parameters expansion code hits the
exception for "std::string" and doesn't expand it, so the breakpoint
fails to be inserted, because the symbol that exists is really the
f(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >)
one, not "f(std::string)".
So to fix things for C++11 ABI, clearly we need to remove the
"std::string" exception from the typedef-in-parameters expansion
logic. If we do just that, then "b f(std::string)" starts working
with the C++11 ABI.
However, if we do _just_ that, and nothing else, then we break
pre-C++11 ABI...
The solution is then to in addition switch GDB to always use
DMGL_VERBOSE. If we do this, then pre-C++11 ABI symbols works the
same as C++11 ABI symbols overall -- the demangler expands the
standard abbreviation for "std::string" as "std::basic_string<char,
std::char_traits<char>, std::allocator<char> >" and letting GDB expand
the "std::string" typedef (etc.) too is no longer a problem.
To avoid getting in the situation where some parts of GDB use
DMGL_VERBOSE and others not, this patch adds wrappers around the
demangler's entry points that GDB uses, and makes those force
DMGL_VERBOSE.
The point of the gdb.cp/no-dmgl-verbose.exp testcase was to try to
ensure that DMGL_VERBOSE doesn't creep back in:
gdb_test {break 'f(std::basic_string<char, std::char_traits<char>, std::allocator<char> >)'} \
{Function ".*" not defined\.} \
"DMGL_VERBOSE-demangled f(std::string) is not defined"
This obviously no longer makes sense to have, since we now depend on
DMGL_VERBOSE. So the patch replaces gdb.cp/no-dmgl-verbose.exp with a
new gdb.cp/break-f-std-string.exp testcase whose purpose is to make
sure that setting a breakpoint at "f(std::string)" works. It
exercises both pre-C++11 ABI and C++11 ABI.
Change-Id: Ib54fab4cf0fd307bfd55bf1dd5056830096a653b
Replace with calls to blockvector::blocks, and the appropriate method
call on the returned array_view.
Change-Id: I04d1f39603e4d4c21c96822421431d9a029d8ddd
Now that filtered and unfiltered output can be treated identically, we
can unify the printf family of functions. This is done under the name
"gdb_printf". Most of this patch was written by script.
This patch adds support for wild template parameter list matches, similar
to how ABI tags or function overloads are now handled.
With this patch, users will be able to "gloss over" the details of matching
template parameter lists. This is accomplished by adding (yet more) logic
to strncmp_iw_with_mode to skip parameter lists if none is explicitly given
by the user.
Here's a simple example using gdb.linespec/cpls-ops.exp:
Before
------
(gdb) ptype test_op_call
type = struct test_op_call {
public:
void operator()(void);
void operator()(int);
void operator()(long);
void operator()<int>(int *);
}
(gdb) b test_op_call::operator()
Breakpoint 1 at 0x400583: test_op_call::operator(). (3 locations)
(gdb) i b
Num Type Disp Enb Address What
1 breakpoint keep y <MULTIPLE>
1.1 y 0x400583 in test_op_call::operator()(int)
at cpls-ops.cc:43
1.2 y 0x40058e in test_op_call::operator()()
at cpls-ops.cc:47
1.3 y 0x40059e in test_op_call::operator()(long)
at cpls-ops.cc:51
The breakpoint at test_op_call::operator()<int> was never set.
After
-----
(gdb) b test_op_call::operator()
Breakpoint 1 at 0x400583: test_op_call::operator(). (4 locations)
(gdb) i b
Num Type Disp Enb Address What
1 breakpoint keep y <MULTIPLE>
1.1 y 0x400583 in test_op_call::operator()(int)
at cpls-ops.cc:43
1.2 y 0x40058e in test_op_call::operator()()
at cpls-ops.cc:47
1.3 y 0x40059e in test_op_call::operator()(long)
at cpls-ops.cc:51
1.4 y 0x4008d0 in test_op_call::operator()<int>(int*)
at cpls-ops.cc:57
Similar to how scope lookups work, passing "-qualified" to the break command
will cause a literal lookup of the symbol. In the example immediately above,
this will cause GDB to only find the three non-template functions.
Add a getter and a setter for a symbol's type. Remove the corresponding
macro and adjust all callers.
Change-Id: Ie1a137744c5bfe1df4d4f9ae5541c5299577c8de
Add a getter and a setter for a compunit_symtab's blockvector. Remove
the corresponding macro and adjust all callers.
Change-Id: I99484c6619dcbbea7c5d89c72aa660316ca62f64
Many otherwise ordinary commands choose to use unfiltered output
rather than filtered. I don't think there's any reason for this, so
this changes many such commands to use filtered output instead.
Note that complete_command is not touched due to a comment there
explaining why unfiltered output is believed to be used.
This commit brings all the changes made by running gdb/copyright.py
as per GDB's Start of New Year Procedure.
For the avoidance of doubt, all changes in this commits were
performed by the script.
There are some loops in gdb that use ARRAY_SIZE (or a wordier
equivalent) to loop over a static array. This patch changes some of
these to use foreach instead.
Regression tested on x86-64 Fedora 34.
I noticed that some methods in language_defn could use
unique_xmalloc_ptr<char> rather than a plain 'char *'. This patch
implements this change, fixing up the fallout and changing
gdb_demangle to also return this type. In one spot, std::string is
used to simplify some related code, and in another, an auto_obstack is
used to avoid manual management.
Regression tested on x86-64 Fedora 34.
I noticed that pointer_type is declared in language.h and defined in
language.c. However, it really has to do with types, so it should
have been in gdbtypes.h all along.
This patch changes it to be a method on struct type. And, I went
through uses of TYPE_IS_REFERENCE and updated many spots to use the
new method as well. (I didn't update ones that were in arch-specific
code, as I couldn't readily test that.)
Same idea as previous patch, but for add_alias_cmd. Remove the overload
that accepts the target command as a string (the target command name),
leaving only the one that takes the cmd_list_element.
gdb/ChangeLog:
* command.h (add_alias_cmd): Accept target as
cmd_list_element. Update callers.
Change-Id: I546311f411e9e7da9302322d6ffad4e6c56df266
Previously, the prefixname field of struct cmd_list_element was manually
set for prefix commands. This seems verbose and error prone as it
required every single call to functions adding prefix commands to
specify the prefix name while the same information can be easily
generated.
Historically, this was not possible as the prefix field was null for
many commands, but this was fixed in commit
3f4d92ebdf by Philippe Waroquiers, so
we can rely on the prefix field being set when generating the prefix
name.
This commit also fixes a use after free in this scenario:
* A command gets created via Python (using the gdb.Command class).
The prefix name member is dynamically allocated.
* An alias to the new command is created. The alias's prefixname is set
to point to the prefixname for the original command with a direct
assignment.
* A new command with the same name as the Python command is created.
* The object for the original Python command gets freed and its
prefixname gets freed as well.
* The alias is updated to point to the new command, but its prefixname
is not updated so it keeps pointing to the freed one.
gdb/ChangeLog:
* command.h (add_prefix_cmd): Remove the prefixname argument as
it can now be generated automatically. Update all callers.
(add_basic_prefix_cmd): Ditto.
(add_show_prefix_cmd): Ditto.
(add_prefix_cmd_suppress_notification): Ditto.
(add_abbrev_prefix_cmd): Ditto.
* cli/cli-decode.c (add_prefix_cmd): Ditto.
(add_basic_prefix_cmd): Ditto.
(add_show_prefix_cmd): Ditto.
(add_prefix_cmd_suppress_notification): Ditto.
(add_prefix_cmd_suppress_notification): Ditto.
(add_abbrev_prefix_cmd): Ditto.
* cli/cli-decode.h (struct cmd_list_element): Replace the
prefixname member variable with a method which generates the
prefix name at runtime. Update all code reading the prefix
name to use the method, and remove all code setting it.
* python/py-cmd.c (cmdpy_destroyer): Remove code to free the
prefixname member as it's now a method.
(cmdpy_function): Determine if the command is a prefix by
looking at prefixlist, not prefixname.
This introduces wrappers for each function in quick_symbol_functions.
The wrappers are methods on objfile, and are defined in
symfile-debug.c, so that they can use the symfile_debug variable.
Places that call the quick functions are all updated to call these new
wrapper methods.
gdb/ChangeLog
2021-03-20 Tom Tromey <tom@tromey.com>
* symtab.c (iterate_over_symtabs, expand_symtab_containing_pc)
(lookup_symbol_via_quick_fns, find_quick_global_symbol_language)
(basic_lookup_transparent_type_quick)
(find_pc_sect_compunit_symtab, find_symbol_at_address)
(find_line_symtab, global_symbol_searcher::expand_symtabs):
Update.
* symmisc.c (print_objfile_statistics, dump_objfile)
(maintenance_expand_symtabs): Update.
* symfile.c (symbol_file_add_with_addrs)
(expand_symtabs_matching, map_symbol_filenames): Update.
* symfile-debug.c (objfile::has_partial_symbols)
(objfile::find_last_source_symtab)
(objfile::forget_cached_source_info)
(objfile::map_symtabs_matching_filename, objfile::lookup_symbol)
(objfile::print_stats, objfile::dump)
(objfile::expand_symtabs_for_function)
(objfile::expand_all_symtabs)
(objfile::expand_symtabs_with_fullname)
(objfile::map_matching_symbols)
(objfile::expand_symtabs_matching)
(objfile::find_pc_sect_compunit_symtab)
(objfile::map_symbol_filenames)
(objfile::find_compunit_symtab_by_address)
(objfile::lookup_global_symbol_language): New methods.
(debug_sym_quick_functions): Remove.
(debug_sym_fns, install_symfile_debug_logging): Update.
* source.c (forget_cached_source_info_for_objfile)
(select_source_symtab): Update.
* objfiles.h (struct objfile): Add methods corresponding to
quick_symbol_functions.
* objfiles.c (objfile::has_partial_symbols): Move to
symfile-debug.c.
* linespec.c (iterate_over_all_matching_symtabs): Update.
* cp-support.c (add_symbol_overload_list_qualified): Update.
* ada-lang.c (add_nonlocal_symbols): Update.
This avoids using a thread-local extern variable, which causes link errors
on some platforms, notably Cygwin. But I think this is a better pattern
even outside of working around linker bugs because it encapsulates direct
access to the variable inside the class, instead of having a global extern
variable.
The cygwin link error is:
cp-support.o: in function `gdb_demangle(char const*, int)':
/home/Christian/binutils-gdb/obj/gdb/../../gdb/cp-support.c:1619:(.text+0x6472): relocation truncated to fit: R_X86_64_PC32 against undefined symbol `TLS init function for thread_local_segv_handler'
/home/Christian/binutils-gdb/obj/gdb/../../gdb/cp-support.c:1619:(.text+0x648b): relocation truncated to fit: R_X86_64_PC32 against undefined symbol `TLS init function for thread_local_segv_handler'
collect2: error: ld returned 1 exit status
2021-03-12 Christian Biesinger <cbiesinger@google.com>
PR threads/27239
* cp-support.c: Use scoped_segv_handler_restore.
* event-top.c (thread_local_segv_handler): Made static.
(scoped_segv_handler_restore::scoped_segv_handler_restore):
New function.
(scoped_segv_handler_restore::~scoped_segv_handler_restore): New
function.
* event-top.h (class scoped_segv_handler_restore): New class.
(thread_local_segv_handler): Removed.
This commits the result of running gdb/copyright.py as per our Start
of New Year procedure...
gdb/ChangeLog
Update copyright year range in copyright header of all GDB files.
