main_type::nfields is a 'short', and has been for many years. PR
c++/29985 points out that 'short' is too narrow for an enum that
contains more than 2^15 constants.
This patch bumps the size of 'nfields'. To verify that the field
isn't directly used, it is also renamed. Note that this does not
affect the size of main_type on x86-64 Fedora 36. And, if it does
have a negative effect somewhere, it's worth considering that types
could be shrunk more drastically by using subclasses for the different
codes.
This is v2 of this patch, which has these changes:
* I changed nfields to 'unsigned', per Simon's request. I looked at
changing all the uses, but this quickly fans out into a very large
patch. (One additional tweak was needed, though.)
* I wrote a test case. I discovered that GCC cannot compile a large
enough C test case, so I resorted to using the DWARF assembler.
This test doesn't reproduce the crash, but it does fail without the
patch.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29985
A patch later in this series will make frame_info_ptr access some
fields internal to frame_info, which we don't want to expose outside of
frame.c. Move the frame_info_ptr class to frame.h, and the definitions
to frame.c. Remove frame-info.c and frame-info.h.
Change-Id: Ic5949759e6262ea0da6123858702d48fe5673fea
Reviewed-By: Bruno Larsen <blarsen@redhat.com>
I hesitated between putting the file in the dwarf2 directory (as
gdb/dwarf2/call-site.h) or in the common directory (as gdb/call-site.h).
The concept of call site is not DWARF-specific, another debug info
reader could provide this information. But as it is, the implementation
is a bit DWARF-specific, as one form it can take is a DWARF expression
and parameters can be defined using a DWARF register number. So I ended up
choosing to put it under dwarf2/. If another debug info reader ever
wants to provide call site information, we can introduce a layer of
abstraction between the "common" call site and the "dwarf2" call site.
The copyright start year comes from the date `struct call_site` was
introduced.
Change-Id: I1cd84aa581fbbf729edc91b20f7d7a6e0377014d
Reviewed-By: Bruno Larsen <blarsen@redhat.com>
I want to move the call_site stuff out of gdbtypes.h, to a new header
file, to break some cyclic include problem. The call_site stuff uses
cu_offset, also defined in gdbtypes.h, so cu_offset also needs to move
somewhere else (otherwise, call-site.h will need to include gdbtypes.h,
and we are back to square 1). I could move cu_offset to the future new
file dwarf2/call-site.h, but it doesn't sound like a good place for it,
at cu_offset is not specific to call sites, it's used throughout
dwarf2/. So, move it to its own file, dwarf2/types.h. For now,
gdbtypes.h includes dwarf2/types.h, but that will be removed once the
call site stuff is moved to its own file.
Move sect_offset with it too. sect_offset is not a DWARF-specific
concept, but for the moment it is only used in dwarf2/.
Change-Id: I1fd2a3b7b67dee789c4874244b044bde7db43d8e
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.
is_nocall_function anticipates only being called for a function or a
method. However, PR gdb/29871 points out a situation where an unusual
expression -- but one that parses to a valid, if extremely weird,
function call -- breaks this assumption.
This patch changes is_nocall_function to remove this assert and
instead simply return 'false' in this case.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29871
A user noticed that TYPE_CODE_FIXED_POINT was not exported by the gdb
Python layer. This patch fixes the bug, and prevents future
occurences of this type of bug.
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.
This changes GDB to use frame_info_ptr instead of frame_info *
The substitution was done with multiple sequential `sed` commands:
sed 's/^struct frame_info;/class frame_info_ptr;/'
sed 's/struct frame_info \*/frame_info_ptr /g' - which left some
issues in a few files, that were manually fixed.
sed 's/\<frame_info \*/frame_info_ptr /g'
sed 's/frame_info_ptr $/frame_info_ptr/g' - used to remove whitespace
problems.
The changed files were then manually checked and some 'sed' changes
undone, some constructors and some gets were added, according to what
made sense, and what Tromey originally did
Co-Authored-By: Bruno Larsen <blarsen@redhat.com>
Approved-by: Tom Tomey <tom@tromey.com>
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
gdbarch implements its own registry-like approach. This patch changes
it to instead use registry.h. It's a rather large patch but largely
uninteresting -- it's mostly a straightforward conversion from the old
approach to the new one.
The main benefit of this change is that it introduces type safety to
the gdbarch registry. It also removes a bunch of code.
One possible drawback is that, previously, the gdbarch registry
differentiated between pre- and post-initialization setup. This
doesn't seem very important to me, though.
When an objfile is destroyed, types that are still in use and
allocated on that objfile are copied. A temporary hash map is created
during this process, and it is allocated on the destroyed objfile's
obstack -- which normally is fine, as that is going to be destroyed
shortly anyway.
However, this approach requires that the objfile be passed to registry
destruction, and this won't be possible in the rewritten registry.
This patch changes the copied type hash table to simply use the heap
instead. It also removes the 'objfile' parameter from
copy_type_recursive, to make this all more clear.
This patch also fixes an apparent bug in copy_type_recursive.
Previously it was copying the dynamic property list to the dying
objfile's obstack:
- = copy_dynamic_prop_list (&objfile->objfile_obstack,
However I think this is incorrect -- that obstack is about to be
destroyed.
If a variable is passed to function in FORTRAN as an argument the
variable is treated as an array with rank zero. GDB currently does
not support the case for assumed rank 0. This patch provides support
for assumed rank 0 and updates the testcase as well.
Without patch:
Breakpoint 1, arank::sub1 (a=<error reading variable:
failed to resolve dynamic array rank>) at assumedrank.f90:11
11 PRINT *, RANK(a)
(gdb) p a
failed to resolve dynamic array rank
(gdb) p rank(a)
failed to resolve dynamic array rank
With patch:
Breakpoint 1, arank::sub1 (a=0) at assumedrank.f90:11
11 PRINT *, RANK(a)
(gdb) p a
$1 = 0
(gdb) p rank(a)
$2 = 0
This patch adds a new dynamic property DYN_PROP_RANK, this property is
read from the DW_AT_rank attribute and stored within the type just
like other dynamic properties.
As arrays with dynamic ranks make use of a single
DW_TAG_generic_subrange to represent all ranks of the array, support
for this tag has been added to dwarf2/read.c.
The final piece of this puzzle is to add support in gdbtypes.c so that
we can resolve an array type with dynamic rank. To do this the
existing resolve_dynamic_array_or_string function is split into two,
there's a new resolve_dynamic_array_or_string_1 core that is
responsible for resolving each rank of the array, while the now outer
resolve_dynamic_array_or_string is responsible for figuring out the
array rank (which might require resolving a dynamic property) and then
calling the inner core.
The resolve_dynamic_range function now takes a rank, which is passed
on to the dwarf expression evaluator. This rank will only be used in
the case where the array itself has dynamic rank, but we now pass the
rank in all cases, this should be harmless if the rank is not needed.
The only small nit is that resolve_dynamic_type_internal actually
handles resolving dynamic ranges itself, which now obviously requires
us to pass a rank value. But what rank value to use? In the end I
just passed '1' through here as a sane default, my thinking is that if
we are in resolve_dynamic_type_internal to resolve a range, then the
range isn't part of an array with dynamic rank, and so the range
should actually be using the rank value at all.
An alternative approach would be to make the rank value a
gdb::optional, however, this ends up adding a bunch of complexity to
the code (e.g. having to conditionally build the array to pass to
dwarf2_evaluate_property, and handling the 'rank - 1' in
resolve_dynamic_array_or_string_1) so I haven't done that, but could,
if people think that would be a better approach.
Finally, support for assumed rank arrays was only fixed very recently
in gcc, so you'll need the latest gcc in order to run the tests for
this.
Here's an example test program:
PROGRAM arank
REAL :: a1(10)
CALL sub1(a1)
CONTAINS
SUBROUTINE sub1(a)
REAL :: a(..)
PRINT *, RANK(a)
END SUBROUTINE sub1
END PROGRAM arank
Compiler Version:
gcc (GCC) 12.0.0 20211122 (experimental)
Compilation command:
gfortran assumedrank.f90 -gdwarf-5 -o assumedrank
Without Patch:
gdb -q assumedrank
Reading symbols from assumedrank...
(gdb) break sub1
Breakpoint 1 at 0x4006ff: file assumedrank.f90, line 10.
(gdb) run
Starting program: /home/rupesh/STAGING-BUILD-2787/bin/assumedrank
Breakpoint 1, arank::sub1 (a=<unknown type in /home/rupesh/STAGING-BUILD-2787
/bin/assumedrank, CU 0x0, DIE 0xd5>) at assumedrank.f90:10
10 PRINT *, RANK(a)
(gdb) print RANK(a)
'a' has unknown type; cast it to its declared type
With patch:
gdb -q assumedrank
Reading symbols from assumedrank...
(gdb) break sub1
Breakpoint 1 at 0x4006ff: file assumedrank.f90, line 10.
(gdb) run
Starting program: /home/rupesh/STAGING-BUILD-2787/bin/assumedrank
Breakpoint 1, arank::sub1 (a=...) at assumedrank.f90:10
10 PRINT *, RANK(a)
(gdb) print RANK(a)
$1 = 1
(gdb) ptype a
type = real(kind=4) (10)
(gdb)
Co-Authored-By: Andrew Burgess <aburgess@redhat.com>
It is better to rename floatformats_ia64_quad to floatformats_ieee_quad
to reflect the reality, and then we can clean up the related code.
As Tom Tromey said [1]:
These files are maintained in gcc and then imported into the
binutils-gdb repository, so any changes to them will have to
be proposed there first.
the related changes have been merged into gcc master now [2], it is time
to do it for gdb.
[1] https://sourceware.org/pipermail/gdb-patches/2022-March/186569.html
[2] https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=b2dff6b2d9d6
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
A large customer program has a function that is partitioned into hot
and cold parts. A variable in a callee of this function is described
using DW_OP_GNU_entry_value, but gdb gets confused when trying to find
the caller. I tracked this down to dwarf2_get_pc_bounds interpreting
the function's changes so that the returned low PC is the "wrong"
function.
Intead, when processing DW_TAG_call_site, the low PC of each range in
DW_AT_ranges should be preserved in the call_site_target. This fixes
the variable lookup in the test case I have.
I didn't write a standalone test for this as it seemed excessively
complicated.
In order to handle the case where a call site target might refer to
multiple addresses, we change the code to use a callback style. Any
spot using call_site_target::address now passes in a callback function
that may be called multiple times.
This makes the data members of call_site_target 'private'. This lets
us remove most of its public API. call_site_to_target_addr is changed
to be a method of this type. This is a preparatory refactoring for
the fix at the end of this series.
call_site_target reuses field_loc_kind and field_location. However,
it has never used the full range of the field_loc_kind enum. In a
subsequent patch, I plan to add a new 'kind' here, so it seemed best
to avoid this reuse and instead introduce new types here.
It is possible for a compiler to optimize a function in a such ways that
the function does not follow the calling convention of the target. In
such situation, the compiler can use the DW_AT_calling_convention
attribute with the value DW_CC_nocall to tell the debugger that it is
unsafe to call the function. The DWARF5 standard states, in 3.3.1.1:
> If the value of the calling convention attribute is the constant
> DW_CC_nocall, the subroutine does not obey standard calling
> conventions, and it may not be safe for the debugger to call this
> subroutine.
Non standard calling convention can affect GDB's assumptions in multiple
ways, including how arguments are passed to the function, how values are
returned, and so on. For this reason, it is unsafe for GDB to try to do
the following operations on a function with marked with DW_CC_nocall:
- call / print an expression requiring the function to be evaluated,
- inspect the value a function returns using the 'finish' command,
- force the value returned by a function using the 'return' command.
This patch ensures that if a command which relies on GDB's knowledge of
the target's calling convention is used on a function marked nocall, GDB
prints an appropriate message to the user and does not proceed with the
operation which is unreliable.
Note that it is still possible for someone to use a vendor specific
value for the DW_AT_calling_convention attribute for example to indicate
the use of an alternative calling convention. This commit does not
prevent this, and target dependent code can be adjusted if one wanted to
support multiple calling conventions.
Tested on x86_64-Linux, with no regression observed.
Change-Id: I72970dae68234cb83edbc0cf71aa3d6002a4a540
Gfortran supports namelists (a Fortran feature); it emits
DW_TAG_namelist and DW_TAG_namelist_item dies. But gdb does not
process these dies and does not support 'print' or 'ptype' commands on
namelist variables.
An attempt to print namelist variables results in gdb bailing out with
the error message as shown below.
(gdb) print nml
No symbol "nml" in current context.
This commit is to make the print and ptype commands work for namelist
variables and its items. Sample output of these commands is shared
below, with fixed gdb.
(gdb) ptype nml
type = Type nml
integer(kind=4) :: a
integer(kind=4) :: b
End Type nml
(gdb) print nml
$1 = ( a = 10, b = 20 )
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.
gdbtypes.h uses core_addr_eq and core_addr_hash in a weird way: taking
the address of a member and then passing this (as a void*) to these
functions.
It seems better to simply inline the ordinary code here. CORE_ADDR is
a scalar so it can be directly compared, and the identity hash
function seems safe to assume as well.
After this, core_addr_eq and core_addr_hash are unused, so this patch
removes them.
Today I re-learned that resolve_dynamic_type can return a type for
which is_dynamic_type returns true. This can happen for an array
whose elements have dynamic type -- the array is reported as dynamic,
but resolving the elements would be incorrect, because each element
might have a different type after resolution.
You can see the special case in resolve_dynamic_array_or_string:
if (ary_dim != NULL && ary_dim->code () == TYPE_CODE_ARRAY)
...
else
...
I looked into having the TYPE_CODE_ARRAY case in
is_dynamic_type_internal follow this same logic, but that breaks down
on the gdb.fortran/dynamic-ptype-whatis.exp test case. In particular
this code in fortran_undetermined::evaluate:
value *callee = std::get<0> (m_storage)->evaluate (nullptr, exp, noside);
if (noside == EVAL_AVOID_SIDE_EFFECTS
&& is_dynamic_type (value_type (callee)))
callee = std::get<0> (m_storage)->evaluate (nullptr, exp, EVAL_NORMAL);
... relies on is_dynamic_type returning true for such an array.
I wasn't really sure of the best way to fix this, so in the meantime I
wrote this patch, which documents the oddity so that I might have a
chance of remembering this in the future.
This changes gdb to check the index that is passed to type::field.
This caught one bug in the Ada code when running the test suite
(actually I found the bug first, then realized that the check would
have helped), so this patch fixes that as well.
Regression tested on x86-64 Fedora 34.
Add accessors for the various location values in struct field. This
lets us assert that when we get a location value of a certain kind (say,
bitpos), the field's location indeed contains a value of that kind.
Remove the SET_FIELD_* macros, instead use the new setters directly.
Update the FIELD_* macros used to access field locations to go through
the getters. They will be removed in a subsequent patch.
There are places where the FIELD_* macros are used on call_site_target
structures, because it contains members of the same name (loc_kind and
loc). For now, I have replicated the getters/setters in
call_site_target. But we could perhaps eventually factor them in a
"location" structure that can be used at both places.
Note that the field structure, being zero-initialized, defaults to a
bitpos location with value 0. While writing this patch, I tried to make
it default to an "unset" location, to catch places where we would miss
setting a field's location. However, I found that some places relied on
the default being "bitpos 0", so I left it as-is. This change could
always be done as follow-up work, making these places explicitly set the
"bitpos 0" location.
I found two issues to fix:
- I got some failures in the gdb.base/infcall-nested-structs-c++.exp
test. They were caused by two functions in amd64-tdep.c using
TYPE_FIELD_BITPOS before checking if the location is of the bitpos
kind, which they do indirectly through `field_is_static`. Simply
move getting the bitpos below the field_is_static call.
- I got a failure in gdb.xml/tdesc-regs.exp. It turns out that in
make_gdb_type_enum, we set enum field values using SET_FIELD_BITPOS,
and later access them through FIELD_ENUMVAL. Fix that by using
set_loc_enumval to set the value.
Change-Id: I53d3734916c46457576ba11dd77df4049d2fc1e8
Consider test-case gdb.trace/entry-values.exp with target board
unix/-fPIE/-pie.
Using this command we have an abbreviated version, and can see the correct
@entry values for foo:
...
$ gdb -q -batch outputs/gdb.trace/entry-values/entry-values \
-ex start \
-ex "break foo" \
-ex "set print entry-values both" \
-ex continue
Temporary breakpoint 1 at 0x679
Temporary breakpoint 1, 0x0000555555554679 in main ()
Breakpoint 2 at 0x55555555463e
Breakpoint 2, 0x000055555555463e in foo (i=0, i@entry=2, j=2, j@entry=3)
...
Now, let's try the same again, but run directly to foo rather than stopping at
main:
...
$ gdb -q -batch outputs/gdb.trace/entry-values/entry-values \
-ex "break foo" \
-ex "set print entry-values both" \
-ex run
Breakpoint 1 at 0x63e
Breakpoint 1, 0x000055555555463e in foo (i=0, i@entry=<optimized out>, \
j=2, j@entry=<optimized out>)
...
So, what explains the difference? Noteworthy, this is a dwarf assembly
test-case, with debug info for foo and bar, but not for main.
In the first case:
- we run to main
- this does not trigger expanding debug info, because there's none for main
- we set a breakpoint at foo
- this triggers expanding debug info. Relocated addresses are used in
call_site info (because the exec is started)
- we continue to foo, and manage to find the call_site info
In the second case:
- we set a breakpoint at foo
- this triggers expanding debug info. Unrelocated addresses are used in
call_site info (because the exec is not started)
- we run to foo
- this triggers objfile_relocate1, but it doesn't update the call_site
info addresses
- we don't manage to find the call_site info
We could fix this by adding the missing call_site relocation in
objfile_relocate1.
This solution however is counter-trend in the sense that we're trying to
work towards the situation where when starting two instances of an executable,
we need only one instance of debug information, implying the use of
unrelocated addresses.
So, fix this instead by using unrelocated addresses in call_site info.
Tested on x86_64-linux.
This fixes all remaining unix/-fno-PIE/-no-pie vs unix/-fPIE/-pie
regressions, like f.i. PR24892.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=24892
Co-Authored-By: Tom de Vries <tdevries@suse.de>
In commit b4c919f7525 "[gdb/symtab] Fix htab_find_slot call in
read_call_site_scope" , I removed the comment:
...
It must be the first field as we overload core_addr_hash and core_addr_eq for
it.
...
for field pc of struct call_site.
However, this was not tested, and when indeed moving field pc to the second
location, we run into a testsuite failure in gdb.trace/entry-values.exp.
This is caused by core_addr_eq (the eq_f function for the htab) being
called with a pointer to the pc field (as passed into htab_find_slot) and a
pointer to a hash table element. Now that pc is no longer the first field,
the pointer to hash table element no longer points to the pc field.
This could be fixed by simply reinstating the comment, but we're trying to
get rid of this kind of tricks that make refactoring more difficult.
Instead, fix this by:
- reverting commit b4c919f7525, apart from the comment removal, such that
we're passing a pointer to element to htab_find_slot
- updating the htab_find_slot call in compunit_symtab::find_call_site
in a similar manner
- adding a call_site_eq and call_site_hash, and using these in the hash table
instead of core_addr_eq and core_addr_hash.
Tested on x86_64-linux, both with and without a trigger patch that moves pc to
the second location in struct call_site.
In read_call_site_scope we have:
...
call_site_local.pc = pc;
slot = htab_find_slot (cu->call_site_htab, &call_site_local, INSERT);
...
The call passes a call_site pointer as element. OTOH, the hashtab is created
using hash_f == core_addr_hash and eq_f == core_addr_eq, so the element
will be accessed through a CORE_ADDR pointer.
This is not wrong (at least in C), given that pc is the first field in
call_site.
Nevertheless, as in call_site_for_pc, make the htab_find_slot call match the
used hash_f and eq_f by using &pc instead:
...
slot = htab_find_slot (cu->call_site_htab, &pc, INSERT);
...
Tested on x86_64-linux.
Co-Authored-By: Tom de Vries <tdevries@suse.de>
Remove the `TYPE_FIELD_NAME` and `FIELD_NAME` macros, changing all the
call sites to use field::name directly.
Change-Id: I6900ae4e1ffab1396e24fb3298e94bf123826ca6
