Most places in gdb that create a new symbol will apply a section
offset to the address. It seems to me that the choice of offset here
is also an implicit choice of the section. This is particularly true
if you examine fixup_section, which notes that it must be called
before such offsets are applied -- meaning that if any such call has
an effect, it's purely by accident.
This patch cleans up this area by tracking the section index and
applying it to a symbol when the address is set. This is done for
nearly every case -- the remaining cases will be handled in later
patches.
This changes the cooked_index_functions to avoid an extra null check
now that checked_static_cast allows a null argument.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
I propose to rename cooked_index_vector and cooked_index such that the
"main" object, that is the entry point to the index, is called
cooked_index. The fact that the cooked index is implemented as a vector
of smaller indexes is an implementation detail.
This patch renames cooked_index to cooked_index_shard. The following
patch renames cooked_index_vector to cooked_index.
Change-Id: Id650f97dcb23c48f8409fa0974cd093ca0b75177
Approved-By: Tom Tromey <tom@tromey.com>
Since commit 7d82b08e9e ("gdb/dwarf: dump cooked index contents in
cooked_index_functions::dump"), we see:
maint print objfiles /home/smarchi/build/binutils-gdb/gdb/testsuite/outputs/gdb.dwarf2/dw2-error/dw2-error^M
^M
Object file /home/smarchi/build/binutils-gdb/gdb/testsuite/outputs/gdb.dwarf2/dw2-error/dw2-error: Objfile at 0x614000005040, bfd at 0x6120000e08c0, 15 minsyms^M
^M
Cooked index in use:^M
^M
/home/smarchi/src/binutils-gdb/gdb/../gdbsupport/gdb-checked-static-cast.h:58: internal-error: checked_static_cast: Assertion `result != nullptr' failed.^M
A problem internal to GDB has been detected,^M
further debugging may prove unreliable.^M
----- Backtrace -----^M
FAIL: gdb.dwarf2/dw2-error.exp: maint print objfiles /home/smarchi/build/binutils-gdb/gdb/testsuite/outputs/gdb.dwarf2/dw2-error/dw2-error (GDB internal error)
The problem is that when cooked_index_functions fails to build an index,
per_objfile->index_table is nullptr. Therefore, add a nullptr check,
like other methods of cooked_index_functions already do.
Print the "Cooked index in use" message after the nullptr check, such
that if the cooked index failed to build, that message is not printed.
Change-Id: Id67aef592e76c41b1e3bde9838a4e36cef873253
As I am investigating a crash I see with the cooked index, I thought it
would be useful to have a way to dump the index contents. For those not
too familiar with it (that includes me), it can help get a feel of what
it contains and how it is structured.
The cooked_index_functions::dump function is called as part of the
"maintenance print objfiles" command. I tried to make the output
well structured and indented to help readability, as this prints a lot
of text.
The dump function first dumps all cooked index entries, like this:
[25] ((cooked_index_entry *) 0x621000121220)
name: __ioinit
canonical: __ioinit
DWARF tag: DW_TAG_variable
flags: 0x2 [IS_STATIC]
DIE offset: 0x21a4
parent: ((cooked_index_entry *) 0x6210000f9610) [std]
Then the information about the main symbol:
main: ((cooked_index_entry *) 0x621000123b40) [main]
And finally the address map contents:
[1] ((addrmap *) 0x6210000f7910)
[0x0] ((dwarf2_per_cu_data *) 0)
[0x118a] ((dwarf2_per_cu_data *) 0x60c000007f00)
[0x1cc7] ((dwarf2_per_cu_data *) 0)
[0x1cc8] ((dwarf2_per_cu_data *) 0x60c000007f00)
[0x1cdf] ((dwarf2_per_cu_data *) 0)
[0x1ce0] ((dwarf2_per_cu_data *) 0x60c000007f00)
The display of address maps above could probably be improved, to show it
more as ranges, but I think this is a reasonable start.
Note that this patch depends on Pedro Alves' patch "enum_flags
to_string" [1]. If my patch is to be merged before Pedro's series, I
will cherry-pick this patch from his series and merge it before mine.
[1] https://inbox.sourceware.org/gdb-patches/20221212203101.1034916-8-pedro@palves.net/
Change-Id: Ida13e479fd4c8d21102ddd732241778bc3b6904a
This changes the lnp_state_machine constructor to initialize members
directly; and changes lnp_state_machine itself to initialize members
inline when possible.
Reviewed-By: Lancelot Six <lancelot.six@amd.com>
Users of addrmap::find and addrmap::foreach that have a const addrmap
should ideally receive const pointers to objects, to indicate they
should not be modified. However, users that have a non-const addrmap
should still receive a non-const pointer.
To achieve this, without adding more virtual methods, make the existing
find and foreach virtual methods private and prefix them with "do_".
Add small non-const and const wrappers for find and foreach.
Obviously, the const can be cast away, but if using static_cast
instead of C-style casts, then the compiler won't let you cast
the const away. I changed all the callers of addrmap::find and
addrmap::foreach I could find to make them use static_cast.
Change-Id: Ia8e69d022564f80d961413658fe6068edc71a094
When running gdb.ada/arrayptr.exp (and others) on Ubuntu 22.04, with the
`gnat-11` package installed (not `gnat`), with UBSan activated, I get:
(gdb) break foo.adb:40
/home/smarchi/src/binutils-gdb/gdb/dwarf2/read.c:17689:20: runtime error: shift exponent 127 is too large for 64-bit type 'long unsigned int'
The problematic DIEs are:
0x00001460: DW_TAG_subrange_type
DW_AT_lower_bound [DW_FORM_data1] (0x00)
DW_AT_upper_bound [DW_FORM_data16] (ffffffffffffffff3f00000000000000)
DW_AT_name [DW_FORM_strp] ("foo__packed_array___XP7___XDLU_0__1180591620717411303423")
DW_AT_type [DW_FORM_ref4] (0x0000153f "long_long_long_unsigned")
DW_AT_GNAT_descriptive_type [DW_FORM_ref4] (0x0000147e)
DW_AT_artificial [DW_FORM_flag_present] (true)
0x0000153f: DW_TAG_base_type
DW_AT_byte_size [DW_FORM_data1] (0x10)
DW_AT_encoding [DW_FORM_data1] (DW_ATE_unsigned)
DW_AT_name [DW_FORM_strp] ("long_long_long_unsigned")
DW_AT_artificial [DW_FORM_flag_present] (true)
When processed by this code:
negative_mask =
-((ULONGEST) 1 << (base_type->length () * TARGET_CHAR_BIT - 1));
if (low.kind () == PROP_CONST
&& !base_type->is_unsigned () && (low.const_val () & negative_mask))
low.set_const_val (low.const_val () | negative_mask);
When the base type's length (16 bytes in this case) is larger than a
ULONGEST (typically 8 bytes), the bit shift is too large.
My obvious fix is just to skip the fixup for base types larger than a
ULONGEST (8 bytes). I don't think we really handle constant attribute
values larger than 8 bytes anyway, so this is part of a much larger
problem.
Add a test that replicates this situation, but uses bounds that fit in a
signed 64 bit, so we get a sensible result.
Change-Id: I8d0a24f3edd83b44e0761a0ce38922d3e2e112fb
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29386
PR c++/29896 points out a regression in the new DWARF reader. It does
not properly handle a case like "break fn", where "fn" is a template
function.
This happens because the new index uses strncasecmp to compare.
However, to make this work correctly, we need a custom function that
ignores template parameters.
This patch adds a custom comparison function and fixes the bug. A new
test case is included.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29896
The DWARF reader has some code to remove empty indices. However, I
think this code has been obsolete since some earlier changes to
parallel_for_each. This patch removes this code.
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.
Make comp_unit_head.length private, to enforce using accessor functions.
Replace accessor function get_length with get_length_with_initial and
get_length_without_initial, to make it explicit which variant we're using.
Tested on x86_64-linux.
PR symtab/29343
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29343
PR symtab/29343 points out that it would be beneficial if
comp_unit_head had a constructor and used initializers. This patch
implements this. I'm unsure if this is sufficient to close the bug,
but at least it's a step.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29343
When asking GDB to print a variable from an imported namespace, we only
want to see variables imported in lines that the inferior has already
gone through, as is being tested last in gdb.cp/nsusing.exp. However
with the proposed change to gdb.cp/nsusing.exp, we get the following
failures:
(gdb) PASS: gdb.cp/nsusing.exp: continue to breakpoint: marker10 stop
print x
$9 = 911
(gdb) FAIL: gdb.cp/nsusing.exp: print x, before using statement
next
15 y += x;
(gdb) PASS: gdb.cp/nsusing.exp: using namespace M
print x
$10 = 911
(gdb) PASS: gdb.cp/nsusing.exp: print x, only using M
Showing that the feature wasn't functioning properly, it just so
happened that gcc ordered the namespaces in a convenient way.
This happens because GDB doesn't take into account the line where the
"using namespace" directive is written. So long as it shows up in the
current scope, we assume it is valid.
To fix this, add a new member to struct using_direct, that stores the
line where the directive was written, and a new function that informs if
the using directive is valid already.
Unfortunately, due to a GCC bug, the failure still shows up. Compilers
that set the declaration line of the using directive correctly (such as
Clang) do not show such a bug, so the test includes an XFAIL for gcc
code.
Finally, because the final test of gdb.cp/nsusing.exp has turned into
multiple that all would need XFAILs for older GCCs (<= 4.3), and that
GCC is very old, if it is detected, the test just exits early.
Approved-by: Tom Tromey <tom@tromey.com>
PR symtab/29105 shows a number of situations where symbol lookup can
result in the expansion of too many CUs.
What happens is that lookup_signed_typename will try to look up a type
like "signed int". In cooked_index_functions::expand_symtabs_matching,
when looping over languages, the C++ case will canonicalize this type
name to be "int" instead. Then this method will proceed to expand
every CU that has an entry for "int" -- i.e., nearly all of them. A
crucial component of this is that the caller, objfile::lookup_symbol,
does not do this canonicalization, so when it tries to find the symbol
for "signed int", it fails -- causing the loop to continue.
This patch fixes the problem by introducing name canonicalization for
C. The idea here is that, by making C and C++ agree on the canonical
name when a symbol name can have multiple spellings, we avoid the bad
behavior in objfile::lookup_symbol (and any other such code -- I don't
know if there is any).
Unlike C++, C only has a few situations where canonicalization is
needed. And, in particular, due to the lack of overloading (thus
avoiding any issues in linespec) and due to the way c-exp.y works, I
think that no canonicalization is needed during symbol lookup -- only
during symtab construction. This explains why lookup_name_info is not
touched.
The stabs reader is modified on a "best effort" basis.
The DWARF reader needed one small tweak in dwarf2_name to avoid a
regression in dw2-unusual-field-names.exp. I think this is adequately
explained by the comment, but basically this is a scenario that should
not occur in real code, only the gdb test suite.
lookup_signed_typename is simplified. It used to search for two
different type names, but now gdb can search just for the canonical
form.
gdb.dwarf2/enum-type.exp needed a small tweak, because the
canonicalizer turns "unsigned integer" into "unsigned int integer".
It seems better here to use the correct C type name.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29105
Tested-by: Simon Marchi <simark@simark.ca>
Reviewed-by: Andrew Burgess <aburgess@redhat.com>
dwarf2_compute_name has a redundant check of the CU's language -- this
is also checked in dwarf2_canonicalize_name. Removing this slightly
simplifies a future patch.
Reviewed-by: Andrew Burgess <aburgess@redhat.com>
While testing the fix for PR 29105, I noticed I couldn't ctrl-C my way
out of GDB expanding many symtabs. GDB was busy in a loop in
cooked_index_functions::expand_symtabs_matching. Add a QUIT there. I
also happened to see a spot in
cooked_index_functions::expand_matching_symbols where a QUIT would be
useful too, since we iterate over a potentially big number of index
entries and expand CUs in the loop. Add one there too.
Change-Id: Ie1d650381df7f944c16d841b3e592d2dce7306c3
Approved-By: Kevin Buettner <kevinb@redhat.com>
Valgrind reports a leak in the dwarf reader (see details below).
The function dw2_get_file_names_reader is interning in the per_objfile
all the file names it finds, except the name of 'fnd file name and directory'.
Instead, it was xstrdup-ing the name.
Fix the leaks by also interning the name.
This was validated running the tests natively, and under valgrind.
Leaks have decreased as mentionned below.
Valgrind detected no error such as double free or use after free.
Stack trace of the leak:
==4113266== 490,735 bytes in 17,500 blocks are definitely lost in loss record 7,061 of 7,074
==4113266== at 0x483979B: malloc (vg_replace_malloc.c:393)
==4113266== by 0x25A454: xmalloc (alloc.c:57)
==4113266== by 0x7D1E1E: xstrdup (xstrdup.c:34)
==4113266== by 0x39D141: dw2_get_file_names_reader (read.c:2825)
==4113266== by 0x39D141: dw2_get_file_names(dwarf2_per_cu_data*, dwarf2_per_objfile*) (read.c:2851)
==4113266== by 0x39DD6C: dw_expand_symtabs_matching_file_matcher(dwarf2_per_objfile*, gdb::function_view<bool (char const*, bool)>) (read.c:4149)
==4113266== by 0x3BC8B5: cooked_index_functions::expand_symtabs_matching(objfile*, gdb::function_view<bool (char const*, bool)>, lookup_name_info const*, gdb::function_view<bool (char const*)>, gdb::function_view<bool (compunit_symtab*)>, enum_flags<block_search_flag_values>, domain_enum, search_domain) (read.c:18688)
==4113266== by 0x5DD1EA: objfile::map_symtabs_matching_filename(char const*, char const*, gdb::function_view<bool (symtab*)>) (symfile-debug.c:207)
==4113266== by 0x5F04CC: iterate_over_symtabs(char const*, gdb::function_view<bool (symtab*)>) (symtab.c:633)
==4113266== by 0x477EE3: collect_symtabs_from_filename(char const*, program_space*) (linespec.c:3712)
==4113266== by 0x477FC1: symtabs_from_filename(char const*, program_space*) (linespec.c:3726)
==4113266== by 0x47A9B8: convert_explicit_location_spec_to_linespec(linespec_state*, linespec*, char const*, char const*, symbol_name_match_type, char const*, line_offset) (linespec.c:2329)
==4113266== by 0x47E86E: convert_explicit_location_spec_to_sals (linespec.c:2388)
==4113266== by 0x47E86E: location_spec_to_sals(linespec_parser*, location_spec const*) (linespec.c:3104)
==4113266== by 0x47EDAC: decode_line_full(location_spec*, int, program_space*, symtab*, int, linespec_result*, char const*, char const*) (linespec.c:3149)
...
Without the fix, the top 10 leaks are:
./gdb/testsuite/outputs/gdb.base/condbreak-bad/gdb.log:345:==3213924== definitely lost: 130,937 bytes in 5,409 blocks
./gdb/testsuite/outputs/gdb.base/hbreak2/gdb.log:619:==3758919== definitely lost: 173,323 bytes in 7,204 blocks
./gdb/testsuite/outputs/gdb.mi/mi-var-cp/gdb.log:1320:==4152873== definitely lost: 172,826 bytes in 7,207 blocks
./gdb/testsuite/outputs/gdb.base/advance-until-multiple-locations/gdb.log:398:==2992643== definitely lost: 172,965 bytes in 7,211 blocks
./gdb/testsuite/outputs/gdb.mi/mi-var-cmd/gdb.log:2302:==4159476== definitely lost: 173,129 bytes in 7,211 blocks
./gdb/testsuite/outputs/gdb.cp/gdb2384/gdb.log:222:==3811851== definitely lost: 218,106 bytes in 7,761 blocks
./gdb/testsuite/outputs/gdb.cp/mb-templates/gdb.log:310:==3787344== definitely lost: 290,311 bytes in 10,340 blocks
./gdb/testsuite/outputs/gdb.mi/mi-var-rtti/gdb.log:2568:==4158350== definitely lost: 435,427 bytes in 15,507 blocks
./gdb/testsuite/outputs/gdb.mi/mi-catch-cpp-exceptions/gdb.log:1704:==4119722== definitely lost: 435,405 bytes in 15,510 blocks
./gdb/testsuite/outputs/gdb.mi/mi-vla-fortran/gdb.log:768:==4113266== definitely lost: 508,585 bytes in 18,109 blocks
With the fix:
./gdb/testsuite/outputs/gdb.base/fork-running-state/gdb.log:1536:==2924193== indirectly lost: 13,848 bytes in 98 blocks
./gdb/testsuite/outputs/gdb.base/fork-running-state/gdb.log:1675:==2928777== indirectly lost: 13,848 bytes in 98 blocks
./gdb/testsuite/outputs/gdb.python/py-inferior-leak/gdb.log:4729:==3353335== definitely lost: 3,360 bytes in 140 blocks
./gdb/testsuite/outputs/gdb.base/kill-detach-inferiors-cmd/gdb.log:210:==2746927== indirectly lost: 13,246 bytes in 154 blocks
./gdb/testsuite/outputs/gdb.base/inferior-clone/gdb.log:179:==3034984== indirectly lost: 12,921 bytes in 161 blocks
./gdb/testsuite/outputs/gdb.base/interrupt-daemon/gdb.log:209:==3006248== indirectly lost: 20,683 bytes in 174 blocks
./gdb/testsuite/outputs/gdb.threads/watchpoint-fork/gdb.log:714:==3512403== indirectly lost: 20,707 bytes in 175 blocks
./gdb/testsuite/outputs/gdb.threads/watchpoint-fork/gdb.log:962:==3514498== indirectly lost: 20,851 bytes in 178 blocks
./gdb/testsuite/outputs/gdb.base/multi-forks/gdb.log:336:==2585839== indirectly lost: 53,630 bytes in 386 blocks
./gdb/testsuite/outputs/gdb.base/multi-forks/gdb.log:1338:==2592417== indirectly lost: 100,008 bytes in 1,154 blocks
Approved-By: Simon Marchi <simon.marchi@efficios.com>
If we instrument cc-with-tweaks.sh to remove the .gnu_debugaltlink file after
dwz has created it, with test-case
gdb.threads/access-mem-running-thread-exit.exp and target board cc-with-dwz-m
we run into:
...
(gdb) file access-mem-running-thread-exit^M
Reading symbols from access-mem-running-thread-exit...^M
could not find '.gnu_debugaltlink' file for access-mem-running-thread-exit^M
...
followed a bit later by:
...
(gdb) file access-mem-running-thread-exit^M
Reading symbols from access-mem-running-thread-exit...^M
gdb/dwarf2/read.c:7284: internal-error: create_all_units: \
Assertion `per_objfile->per_bfd->all_units.empty ()' failed.^M
...
The problem is that create_units does not catch the error thrown by
dwarf2_get_dwz_file.
Fix this by catching the error and performing the necessary cleanup, getting
the same result for the first and second file command.
PR symtab/29805
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29805
Clang up to version 15 (current) adds macros that were defined in the
command line or by "other means", according to the Dwarf specification,
after the last DW_MACRO_end_file, instead of before the first
DW_MACRO_start_file, as the specification dictates. When GDB reads the
macros after the last file is closed, the macros never end up "in scope"
and so we can't print them. This has been submitted as a bug to Clang
developers (https://github.com/llvm/llvm-project/issues/54506), and PR
macros/29034 was opened for GDB to keep track of this.
Seeing as there is no expected date for it to be fixed, add a workaround
for all current versions of Clang. The workaround detects when
the main file would be closed and if the producer is Clang, and turns
that operation into a noop, so we keep a reference to the current_file
as those macros are read.
A test case was added to confirm the functionality, and the KFAIL for
running gdb.base/macro-source-path when using clang.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29034
Approved-By: Simon Marchi <simon.marchi@efficios.com>
Small cleanup to use std::vector iterators rather than raw pointers.
Approved-By: Tom Tromey <tom@tromey.com>
Change-Id: I8d50dbb3f2d8dad7ff94066a578d523f1f31b590
When building GDB with clang and --enable-ubsan, I get:
UNRESOLVED: gdb.dwarf2/frame-inlined-in-outer-frame.exp: starti prompt
The cause being:
$ ./gdb --data-directory=data-directory -nx -q -readnow testsuite/outputs/gdb.dwarf2/frame-inlined-in-outer-frame/frame-inlined-in-outer-frame
Reading symbols from testsuite/outputs/gdb.dwarf2/frame-inlined-in-outer-frame/frame-inlined-in-outer-frame...
Expanding full symbols from testsuite/outputs/gdb.dwarf2/frame-inlined-in-outer-frame/frame-inlined-in-outer-frame...
/home/simark/src/binutils-gdb/gdb/dwarf2/read.c:11954:47: runtime error: applying non-zero offset 8 to null pointer
I found this to happen with ld-linux on at least Arch Linux and Ubuntu
22.04:
$ ./gdb --data-directory=data-directory -nx -q -readnow -iex "set debuginfod enabled on" /lib64/ld-linux-x86-64.so.2
Reading symbols from /lib64/ld-linux-x86-64.so.2...
Reading symbols from /home/simark/.cache/debuginfod_client/22bd7a2c03d8cfc05ef7092bfae5932223189bc1/debuginfo...
Expanding full symbols from /home/simark/.cache/debuginfod_client/22bd7a2c03d8cfc05ef7092bfae5932223189bc1/debuginfo...
/home/simark/src/binutils-gdb/gdb/dwarf2/read.c:11954:47: runtime error: applying non-zero offset 8 to null pointer
The problem happens when doing this:
sect_offset *offsetp = offsets.data () + 1
When `offsets` is an empty vector, `offsets.data ()` returns nullptr.
Fix it by wrapping that in a `!offsets.empty ()` check.
Change-Id: I6d29ba2fe80ba4308f68effd9c57d4ee8d67c29f
Approved-By: Tom Tromey <tom@tromey.com>
PR symtab/29694 points out a regression caused by the new DWARF
scanner when the cc-with-gdb-index target board is used.
What happens here is that an older version of gdb will make an index
describing the "A" type as:
[737] A: 1 [global, type]
whereas the new gdb says:
[1008] A: 0 [global, type]
Here the old one is correct because the A in CU 0 is just a
declaration without a size:
<1><45>: Abbrev Number: 10 (DW_TAG_structure_type)
<46> DW_AT_name : A
<48> DW_AT_declaration : 1
<48> DW_AT_sibling : <0x6d>
This patch fixes the problem by introducing the idea of a "type
declaration". I think gdb still needs to recurse into these types,
searching for methods, but by marking the type itself as a
declaration, gdb can skip this type during lookups and when writing
the index.
Regression tested on x86-64 using the cc-with-gdb-index board.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29694
A user found a bug where an array of packed arrays was printed
incorrectly. The bug here is that the packed array has a bit stride,
but the outer array does not -- and should not. However,
update_static_array_size does not distinguish between an array of
packed arrays and a multi-dimensional packed array, and for the
latter, only the innermost array will end up with a stride.
This patch fixes the problem by adding a flag to indicate whether a
given array type is a constituent of a multi-dimensional array.
The compiler will sometimes emit a linkage name for a type, like:
<1d3> DW_AT_linkage_name: (indirect string, offset: 0x106f): 11__mbstate_t
These names aren't very useful, and this patch changes the DWARF
reader so that they are ignored by the cooked index.
This patch changes a few more uses of static_cast to use
checked_static_cast. In this patch, cast-to-references are converted
by moving the dereference outside of the cast, as checked_static_cast
only handles pointers.
After committing 8ba677d356 ("[gdb/symtab] Don't complain about function
decls") I noticed that quite a bit of code in read_func_scope is used to decide
whether to issue the "cannot get low and high bounds for subprogram DIE at
$hex" complaint, which executes unnecessarily if we have the default
"set complaints 0".
Fix this by (NFC):
- factoring out new static function have_complaint from macro complaint, and
- using it to wrap the relevant code in read_func_scope.
Tested on x86_64-linux.
[ Requires "[gdb/symtab] Don't complain about inlined functions" as
submitted here (
https://sourceware.org/pipermail/gdb-patches/2022-September/191762.html ). ]
With the test-case included in this patch, we get:
...
(gdb) ptype main^M
During symbol reading: cannot get low and high bounds for subprogram DIE \
at 0xc1^M
type = int (void)^M
(gdb) FAIL: gdb.dwarf2/anon-ns-fn.exp: ptype main without complaints
...
The DIE causing the complaint is a function declaration:
...
<2><c1>: Abbrev Number: 3 (DW_TAG_subprogram)
<c2> DW_AT_name : foo
<c8> DW_AT_declaration : 1
...
which is referred to from the DIE representing the function definition:
...
<1><f4>: Abbrev Number: 7 (DW_TAG_subprogram)
<f5> DW_AT_specification: <0xc1>
<f9> DW_AT_low_pc : 0x4004c7
<101> DW_AT_high_pc : 0x7
...
which does contain the low and high bounds.
Fix this by not complaining about function declarations.
Tested on x86_64-linux.
With the test-case included in this patch, we get:
...
(gdb) ptype main^M
During symbol reading: cannot get low and high bounds for subprogram DIE \
at 0x113^M
During symbol reading: cannot get low and high bounds for subprogram DIE \
at 0x11f^M
type = int (void)^M
(gdb) FAIL: gdb.dwarf2/inline.exp: ptype main
...
The complaints are about foo, with DW_AT_inline == DW_INL_inlined:
...
<1><11f>: Abbrev Number: 6 (DW_TAG_subprogram)
<120> DW_AT_name : foo
<126> DW_AT_prototyped : 1
<126> DW_AT_type : <0x10c>
<12a> DW_AT_inline : 1 (inlined)
...
and foo2, with DW_AT_inline == DW_INL_declared_inlined:
...
<1><113>: Abbrev Number: 5 (DW_TAG_subprogram)
<114> DW_AT_name : foo2
<11a> DW_AT_prototyped : 1
<11a> DW_AT_type : <0x10c>
<11e> DW_AT_inline : 3 (declared as inline and inlined)
...
Fix this by not complaining about inlined functions.
Tested on x86_64-linux.
Add all_comp_units/all_type_units views on all_units.
Having the views allows us to:
- easily get the number of CUs or TUs in all_units, and
- easily access the nth CU or TU.
This minimizes the use of tu_stats.nr_tus.
Tested on x86_64-linux.
Add the `length` and `set_length` methods on `struct type`, in order to remove
the `TYPE_LENGTH` macro. In this patch, the macro is changed to use the
getter, so all the call sites of the macro that are used as a setter are
changed to use the setter method directly. The next patch will remove the
macro completely.
Change-Id: Id1090244f15c9856969b9be5006aefe8d8897ca4
Add the `target_type` and `set_target_type` methods on `struct type`, in order
to remove the `TYPE_TARGET_TYPE` macro. In this patch, the macro is changed to
use the getter, so all the call sites of the macro that are used as a setter
are changed to use the setter method directly. The next patch will remove the
macro completely.
Change-Id: I85ce24d847763badd34fdee3e14b8c8c14cb3161
With the test-case included in this commit, we run into this FAIL:
...
(gdb) p var^M
During symbol reading: file index out of range^M
$1 = 0^M
(gdb) FAIL: gdb.dwarf2/dw2-no-code-cu.exp: p var with no complaints
...
This is a regression since commit 6d263fe46e ("Avoid bad breakpoints with
--gc-sections"), which contains this change in read_file_scope:
...
- handle_DW_AT_stmt_list (die, cu, fnd, lowpc);
+ if (lowpc != highpc)
+ handle_DW_AT_stmt_list (die, cu, fnd, lowpc);
...
The change intends to avoid a problem with a check in
lnp_state_machine::check_line_address, but also prevents the file and dir
tables from being read, which causes the complaint.
Fix the FAIL by reducing the scope of the "lowpc != highpc" condition to the
call to dwarf_decode_lines in handle_DW_AT_stmt_list.
Tested on x86_64-linux.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29561
With the test-case included in the patch, we run into:
...
(gdb) info types -q std::nullptr_t^M
During symbol reading: unsupported tag: 'DW_TAG_unspecified_type'^M
^M
File /usr/include/c++/7/x86_64-suse-linux/bits/c++config.h:^M
2198: typedef decltype(nullptr) std::nullptr_t;^M
(gdb) FAIL: gdb.dwarf2/nullptr_t.exp: info types -q std::nullptr_t \
without complaint
...
Fix the complaint by handling DW_TAG_unspecified_type in new_symbol, and verify
in the test-case using "maint print symbols" that the symbol exists.
Tested on x86_64-linux, with gcc 7.5.0 and clang 13.0.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=17271
Currently, the test-case contained in this patch fails:
...
(gdb) p (int) foo ()^M
Invalid cast.^M
(gdb) FAIL: gdb.dwarf2/dw2-unspecified-type.exp: p (int) foo ()
...
because DW_TAG_unspecified_type is translated as void.
There's some code in read_unspecified_type that marks the type as stub, but
that's only active for ada:
...
if (cu->lang () == language_ada)
type->set_is_stub (true);
...
Fix this by:
- marking the type as a stub for all languages, and
- handling the stub return type case in call_function_by_hand_dummy.
Tested on x86_64-linux.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29558
When running test-case gdb.cp/cpexprs-debug-types.exp on target board
cc-with-debug-names/gdb:debug_flags=-gdwarf-5, we get an executable with
a .debug_names section, but no .debug_types section. For dwarf-5, the TUs
are no longer put in a separate unit, but instead they're put in the
.debug_info section.
When loading the executable, the .debug_names section is silently ignored
because of this check in dwarf2_read_debug_names:
...
if (map->tu_count != 0)
{
/* We can only handle a single .debug_types when we have an
index. */
if (per_bfd->types.size () != 1)
return false;
...
which triggers because per_bfd->types.size () == 0.
The intention of the check is to make sure we don't have more that one
.debug_types section, as can happen in a object file (see PR12984):
...
$ grep "\.debug_types" 11.s
.section .debug_types,"G",@progbits,wt.75c042c23a9a07ee,comdat
.section .debug_types,"G",@progbits,wt.c59c413bf50a4607,comdat
...
Fix this by:
- changing the check condition to "per_bfd->types.size () > 1", and
- handling per_bfd->types.size () == 0.
Tested on x86_64-linux.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29385
The following GDB behavior was also reported as a GDB bug in
https://sourceware.org/bugzilla/show_bug.cgi?id=28396
I will reiterate the problem a bit and give some more information here.
This patch closes the above mentioned bug.
The DWARF 5 standard 2.23 'Template Parameters' reads:
A template type parameter is represented by a debugging information
entry with the tag DW_TAG_template_type_parameter. A template value
parameter is represented by a debugging information entry with the tag
DW_TAG_template_value_parameter. The actual template parameter entries
appear in the same order as the corresponding template formal
parameter declarations in the source progam.
A type or value parameter entry may have a DW_AT_name attribute, whose
value is a null-terminated string containing the name of the
corresponding formal parameter.
So the DW_AT_name attribute for DW_TAG_template_type_parameter and
DW_TAG_template_value_parameter is optional.
Within GDB, creating a new symbol from some read DIE usually requires the
presence of a DW_AT_name for the DIE (an exception here is the case of
unnamed namespaces or the existence of a linkage name).
This patch makes the presence of the DW_AT_name for template value/type
tags optional, similar to the unnamed namespaces.
For unnamed namespaces dwarf2_name simply returns the constant string
CP_ANONYMOUS_NAMESPACE_STR '(anonymous namespace)'. For template tags a
case was added to the switch statement calling the
unnamed_template_tag_name helper. Within the scope of parent which
the template parameter is a child of, the helper counts the position
of the template tag within the unnamed template tags and returns
'<unnamedNUMBER>' where NUMBER is its position. This way we end up with
unique names within the respective scope of the function/class/struct
(these are the only currenltly supported template kinds within GDB and
usually the compilers) where we discovered the template tags in.
While I do not know of a way to bring GCC to emit template tags without
names there is one for clang/icpx. Consider the following example
template<typename A, typename B, typename C>
class Foo {};
template<typename, typename B, typename>
class Foo;
int main () {
Foo<double, int, float> f;
return 0;
}
The forward declaration for 'Foo' with the missing template type names
'A' and 'C' makes clang emit a bunch of template tags without names:
...
<2><43>: Abbrev Number: 3 (DW_TAG_variable)
<44> DW_AT_location : 2 byte block: 91 78 (DW_OP_fbreg: -8)
<47> DW_AT_name : (indirect string, offset: 0x63): f
<4b> DW_AT_decl_file : 1
<4c> DW_AT_decl_line : 8
<4d> DW_AT_type : <0x59>
...
<1><59>: Abbrev Number: 5 (DW_TAG_class_type)
<5a> DW_AT_calling_convention: 5 (pass by value)
<5b> DW_AT_name : (indirect string, offset: 0x74): Foo<double, int, float>
<5f> DW_AT_byte_size : 1
<60> DW_AT_decl_file : 1
<61> DW_AT_decl_line : 2
<2><62>: Abbrev Number: 6 (DW_TAG_template_type_param)
<63> DW_AT_type : <0x76>
<2><67>: Abbrev Number: 7 (DW_TAG_template_type_param)
<68> DW_AT_type : <0x52>
<6c> DW_AT_name : (indirect string, offset: 0x6c): B
<2><70>: Abbrev Number: 6 (DW_TAG_template_type_param)
<71> DW_AT_type : <0x7d>
...
Befor this patch, GDB would not create any symbols for the read template
tag DIEs and thus lose knowledge about them. Breaking at the return
statement and printing f's type would read
(gdb) ptype f
type = class Foo<double, int, float> [with B = int] {
<no data fields>
}
After this patch GDB does generate symbols from the DWARF (with their
artificial names:
(gdb) ptype f
type = class Foo<double, int, float> [with <unnamed0> = double, B = int,
<unnamed1> = float] {
<no data fields>
}
The same principle theoretically applies to template functions. Also
here, GDB would not record unnamed template TAGs but I know of no visual
way to trigger and test this changed behavior. Template functions do
not emit a '[with...]' list and their name generation also does not
suffer from template tags without names. GDB does not check whether or
not a template tag has a name in 'dwarf2_compute_name' and thus, the
names of the template functions are created independently of whether or
not the template TAGs have a DW_TAT_name attribute. A testcase has
been added in the gdb.dwarf2 for template classes and structs.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=28396
When running the included test-case, we run into:
...
(gdb) break _start^M
read.h:309: internal-error: set_length: \
Assertion `m_length == length' failed.^M
...
The problem is that while there are two CUs:
...
$ readelf -wi debug-names-missing-cu | grep @
Compilation Unit @ offset 0x0:
Compilation Unit @ offset 0x2d:
...
the CU table in the .debug_names section only contains the first one:
...
CU table:
[ 0] 0x0
...
The incomplete CU table makes create_cus_from_debug_names_list set the size of
the CU at 0x0 to the actual size of both CUs combined.
This eventually leads to the assert, when we read the actual size from the CU
header.
While having an incomplete CU table in a .debug_names section is incorrect,
we need a better failure mode than asserting.
The easiest way to fix this is to set the length to 0 (meaning: unkown) in
create_cus_from_debug_names_list.
This makes the failure mode to accept the incomplete CU table, but to ignore
the missing CU.
It would be nice to instead reject the .debug_names index, and build a
complete CU list, but the point where we find this out is well after
dwarf2_initialize_objfile, so it looks rather intrusive to restart at that
point.
Tested on x86_64-linux.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29453
