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272 commits

Author SHA1 Message Date
Joel Brobecker
213516ef31 Update copyright year range in header of all files managed by GDB
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.
2023-01-01 17:01:16 +04:00
Simon Marchi
df86565b31 gdb: remove TYPE_LENGTH
Remove the macro, replace all uses with calls to type::length.

Change-Id: Ib9bdc954576860b21190886534c99103d6a47afb
2022-09-21 11:05:21 -04:00
Simon Marchi
27710edb4e gdb: remove TYPE_TARGET_TYPE
Remove the macro, replace all uses by calls to type::target_type.

Change-Id: Ie51d3e1e22f94130176d6abd723255282bb6d1ed
2022-09-21 10:59:49 -04:00
Tom Tromey
cb275538db Use registry in gdbarch
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.
2022-08-04 13:28:04 -06:00
Nils-Christian Kempke
891e4190ba gdb/fortran: rewrite intrinsic handling and add some missing overloads
The operators FLOOR, CEILING, CMPLX, LBOUND, UBOUND, and SIZE accept
(some only with Fortran 2003) the optional parameter KIND.  This
parameter determines the kind of the associated return value.  So far,
implementation of this kind parameter has been missing in GDB.
Additionally, the one argument overload for the CMPLX intrinsic function
was not yet available.

This patch adds overloads for all above mentioned functions to the
Fortran intrinsics handling in GDB.

It re-writes the intrinsic function handling section to use the helper
methods wrap_unop_intrinsic/wrap_binop_intrinsic/wrap_triop_intrinsic.
These methods define the action taken when a Fortran intrinsic function
is called with a certain amount of arguments (1/2/3). The helper methods
fortran_wrap2_kind and fortran_wrap3_kind have been added as equivalents
to the existing wrap and wrap2 methods.

After adding more overloads to the intrinsics handling, some of the
operation names were no longer accurate.  E.g. UNOP_FORTRAN_CEILING
has been renamed to FORTRAN_CEILING as it is no longer a purely unary
intrinsic function.  This patch also introduces intrinsic functions with
one, two, or three arguments to the Fortran parser and the
UNOP_OR_BINOP_OR_TERNOP_INTRINSIC token has been added.
2022-04-11 14:06:56 +02:00
Nils-Christian Kempke
87abd9825d gdb/fortran: Change GDB print for fortran default types
Currently, when asking GDB to print the type of a Fortran default type
such as INTEGER or REAL, GDB will return the default name of that type,
e.g. "integer"/"real":

   (gdb) ptype integer
   type = integer
   (gdb) ptype real
   type = real

For LOGICAL and COMPLEX it would return the actual underlying types

   (gdb) ptype logical
   type = logical*4
   (gdb) ptype complex
   type = complex*4

Similarly, GDB would print the default integer type for the underlying
default type:

   (gdb) ptype integer*4
   type = integer
   (gdb) ptype real*4
   type = real
   (gdb) ptype logical
   type = logical*4
   (gdb) ptype complex*4
   type = complex*4

This is inconsistent and a bit confusing.  Both options somehow indicate
what the internal underlying type for the default type is - but I think
the logical/complex version is a bit clearer.

Consider again:

   (gdb) ptype integer
   type = integer

This indicates to a user that the type of "integer" is Fortran's default
integer type.  Without examining "ptype integer*4" I would expect, that
any variable declared integer in the actual code would also fit into a
GDB integer.  But, since we cannot adapt out internal types to the
compiler flags used at compile time of a debugged binary, this might be
wrong.  Consider debugging Fortran code compiled with GNU and e.g. the
"-fdefault-integer-8" flag.  In this case the gfortran default integer
would be integer*8 while GDB internally still would use a builtin_integer,
so an integer of the size of an integer*4 type.  On the other hand having
GDB print

   (gdb) ptype integer
   type = integer*4

makes this clearer.  I would still be tempted to fit a variable declared
integer in the code into a GDB integer - but at least ptype would
directly tell me what is going on.  Note, that when debugging a binary
compiled with "-fdefault-integer-8" a user will always see the actual
underlying type of any variable declared "integer" in the Fortran code.
So having the code

   program test
     integer :: a = 5
     print *, a ! breakpt
   end program test

will, when breaking at breakpt print

   (gdb) ptype var
   type = integer(kind=4)

or

   (gdb) ptype var
   type = integer(kind=8)

depending on the compiler flag.

This patch changes the outputs for the REAL and INTEGER default types to
actually print the internally used type over the default type name.

The new behavior for the above examples is:

   (gdb) ptype integer
   type = integer*4
   (gdb) ptype integer*4
   type = integer*4

Existing testcases have been adapted to reflect the new behavior.
2022-04-11 14:06:56 +02:00
Nils-Christian Kempke
adc29023a7 gdb/fortran: clean-up Fortran intrinsic types
The currently implemented intrinsic type handling for Fortran missed some
tokens and their parsing.  While still not all Fortran type kinds are
implemented this patch at least makes the currently handled types
consistent.  As an example for what this patch does, consider the
intrinsic type INTEGER.  GDB implemented the handling of the
keywords "integer" and "integer_2" but missed "integer_4" and "integer_8"
even though their corresponding internal types were already available as
the Fortran builtin types builtin_integer and builtin_integer_s8.
Similar problems applied to LOGICAL, REAL, and COMPLEX.  This patch adds
all missing tokens and their parsing.  Whenever a section containing the
type handling was touched, it also was reordered to be in a more easy to
grasp order.  All INTEGER/REAL/LOGICAL/COMPLEX types were grouped
together and ordered ascending in their size making a missing one more
easy to spot.

Before this change GDB would print the following when tyring to use the
INTEGER keywords:

   (gdb) set language fortran
   (gdb) ptype integer*1
   unsupported kind 1 for type integer
   (gdb) ptype integer_1
   No symbol table is loaded.  Use the "file" command.
   (gdb) ptype integer*2
   type = integer*2
   (gdb) ptype integer_2
   type = integer*2
   (gdb) ptype integer*4
   type = integer
   (gdb) ptype integer_4
   No symbol table is loaded.  Use the "file" command.
   (gdb) ptype integer*8
   type = integer*8
   (gdb) ptype integer_8
   No symbol table is loaded.  Use the "file" command.
   (gdb) ptype integer
   type = integer

With this patch all keywords are available and the GDB prints:

   (gdb) set language fortran
   (gdb) ptype integer*1
   type = integer*1
   (gdb) ptype integer_1
   type = integer*1
   (gdb) ptype integer*2
   type = integer*2
   (gdb) ptype integer_2
   type = integer*2
   (gdb) ptype integer*4
   type = integer*4
   (gdb) ptype integer_4
   type = integer*4
   (gdb) ptype integer*8
   type = integer*8
   (gdb) ptype integer_8
   type = integer*8
   (gdb) ptype integer
   type = integer

The described changes have been applied to INTEGER, REAL, COMPLEX,
and LOGICAL. Existing testcases have been adapted to reflect the
new behavior.  Tests for formerly missing types have been added.
2022-04-11 14:06:56 +02:00
Nils-Christian Kempke
4ec8aa9e94 gdb/fortran: change default logical type to builtin_logical
According to the Fortran standard, logical is of the size of a
'single numeric storage unit' (just like real and integer). For
gfortran, flang and ifx/ifort this storage unit (or the default
logical type) is of size kind 4, actually occupying 4 bytes of
storage, and so the default type for logical expressions in
Fortran should probably also be Logical*4 and not Logical*2.  I
adapted GDB's behavior to be in line with
gfortran/ifort/ifx/flang.
2022-04-11 14:06:55 +02:00
Nils-Christian Kempke
ed9ec61174 gdb/fortran: reformat build_fortran_types in f-lang.c
Add a few newlines after the type definitions and remove some
unnecessary linebreaks.
2022-04-11 14:06:55 +02:00
Nils-Christian Kempke
4e436fdabe gdb/fortran: fix complex type in Fortran builtin types
Before this patch things like

  (gdb) ptype complex*8
  complex*16
  (gdb) ptype complex*4
  complex*8

were possible in GDB, which seems confusing for a user.  The reason
is a mixup in the implementation of the Fortran COMPLEX type.  In
Fortran the "*X" after a type would normally (I don't think this
is language required) specify the type's size in memory.  For the
COMPLEX type the kind parameters usually (at least for GNU, Intel, Flang)
specify not the size of the whole type but the size of the individual
two REALs used to form the COMPLEX.  Thus, a COMPLEX*4 will usually
consist of two REAL*4s.  Internally this type was represented by a
builtin_complex_s8 - but here I think the s8 actually meant the raw
size of the type.  This is confusing and I renamed the types (e.g.
builting_complex_s8 became builtin_complex_s4 according to its most
common useage) and their printed names to their language equivalent.
Additionally, I added the default COMPLEX type "COMPLEX" being the same
as a COMPLEX*4 (as is normally the case) and removed the latter.  I added
a few tests for this new behavior as well.

The new behavior is

  (gdb) ptype complex*8
  complex*8
  (gdb) ptype complex*4
  complex*4
2022-04-11 14:06:55 +02:00
Nils-Christian Kempke
c08ec64081 gdb/f-lang: remove hidden ^L characters 2022-04-11 14:06:55 +02:00
Nils-Christian Kempke
d4c948427d gdb/f-lang: add Integer*1 to Fortran builtin types
Add builtin_integer_s1 of size TARGET_CHAR_BIT to Fortran builtin types.
2022-04-11 14:06:55 +02:00
Tom Tromey
6cb06a8cda Unify gdb printf functions
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.
2022-03-29 12:46:24 -06:00
Maciej W. Rozycki
5d4c63a635 Respect `set print array-indexes' with Fortran arrays
Add `set print array-indexes' handling for Fortran arrays.  Currently
the setting is ignored and indices are never shown.

Keep track of the most recent index handled so that any outstanding
repeated elements printed when the limit set by `set print elements' is
hit have the correct index shown.

Output now looks like:

(gdb) set print array-indexes on
(gdb) print array_1d
$1 = ((-2) = 1, (-1) = 1, (0) = 1, (1) = 1, (2) = 1)
(gdb) set print repeats 4
(gdb) set print elements 12
(gdb) print array_2d
$2 = ((-2) = ((-2) = 2, <repeats 5 times>) (-1) = ((-2) = 2, <repeats 5 times>) (0) = ((-2) = 2, (-1) = 2, ...) ...)
(gdb)

for a 5-element vector and a 5 by 5 array filled with the value of 2.
2022-01-19 21:55:10 +00:00
Maciej W. Rozycki
476f77a94c Respect `set print repeats' with Fortran arrays
Implement `set print repeats' handling for Fortran arrays.  Currently
the setting is ignored and always treated as if no limit was set.

Unlike the generic array walker implemented decades ago the Fortran one
is a proper C++ class.  Rather than trying to mimic the old walker then,
which turned out a bit of a challenge where interacting with the `set
print elements' setting, write it entirely from scratch, by adding an
extra specialization handler method for processing dimensions other than
the innermost one and letting the specialization class call the `walk_1'
method from the handler as it sees fit.  This way repeats can be tracked
and the next inner dimension recursed into as a need arises only, or
unconditionally in the base class.

Keep track of the dimension number being handled in the class rather as
a parameter to the walker so that it does not have to be passed across
by the specialization class.

Use per-dimension element count tracking, needed to terminate processing
early when the limit set by `set print elements' is hit.  This requires
extra care too where the limit triggers exactly where another element
that is a subarray begins.  In that case rather than recursing we need
to terminate processing or lone `(...)' would be printed.  Additionally
if the skipped element is the last one in the current dimension we need
to print `...' by hand, because `continue_walking' won't print it at the
upper level, because it can see the last element has already been taken
care of.

Preserve the existing semantics of `set print elements' where the total
count of the elements handled is matched against the trigger level which
is unlike with the C/C++ array printer where the per-dimension element
count is used instead.

Output now looks like:

(gdb) set print repeats 4
(gdb) print array_2d
$1 = ((2, <repeats 5 times>) <repeats 5 times>)
(gdb) set print elements 12
(gdb) print array_2d
$2 = ((2, <repeats 5 times>) (2, <repeats 5 times>) (2, 2, ...) ...)
(gdb)

for a 5 by 5 array filled with the value of 2.

Amend existing test cases accordingly that rely on the current incorrect
behavior and explicitly request that there be no limit for printing
repeated elements there.

Add suitable test cases as well covering sliced arrays in particular.

Co-Authored-By: Andrew Burgess <andrew.burgess@embecosm.com>
2022-01-19 21:55:10 +00:00
Joel Brobecker
4a94e36819 Automatic Copyright Year update after running gdb/copyright.py
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.
2022-01-01 19:13:23 +04:00
Simon Marchi
f54bdb6d27 gdb: add add_setshow_prefix_cmd
There's a common pattern to call add_basic_prefix_cmd and
add_show_prefix_cmd to add matching set and show commands.  Add the
add_setshow_prefix_cmd function to factor that out and use it at a few
places.

Change-Id: I6e9e90a30e9efb7b255bf839cac27b85d7069cfd
2021-10-28 10:44:18 -04:00
Simon Marchi
50888e42dc gdb: change functions returning value contents to use gdb::array_view
The bug fixed by this [1] patch was caused by an out-of-bounds access to
a value's content.  The code gets the value's content (just a pointer)
and then indexes it with a non-sensical index.

This made me think of changing functions that return value contents to
return array_views instead of a plain pointer.  This has the advantage
that when GDB is built with _GLIBCXX_DEBUG, accesses to the array_view
are checked, making bugs more apparent / easier to find.

This patch changes the return types of these functions, and updates
callers to call .data() on the result, meaning it's not changing
anything in practice.  Additional work will be needed (which can be done
little by little) to make callers propagate the use of array_view and
reap the benefits.

[1] https://sourceware.org/pipermail/gdb-patches/2021-September/182306.html

Change-Id: I5151f888f169e1c36abe2cbc57620110673816f3
2021-10-25 14:51:44 -04:00
Andrew Burgess
158cc4feb7 gdb: use gdb::optional instead of passing a pointer to gdb::array_view
Following on from the previous commit, this commit changes the API of
value_struct_elt to take gdb::optional<gdb::array_view<value *>>
instead of a pointer to the gdb::array_view.

This makes the optional nature of the array_view parameter explicit.

This commit is purely a refactoring commit, there should be no user
visible change after this commit.

I have deliberately kept this refactor separate from the previous two
commits as this is a more extensive change, and I'm not 100% sure that
using gdb::optional for the parameter type, instead of a pointer, is
going to be to everyone's taste.  If there's push back on this patch
then this one can be dropped from the series.

gdb/ChangeLog:

	* ada-lang.c (desc_bounds): Use '{}' instead of NULL to indicate
	an empty gdb::optional when calling value_struct_elt.
	(desc_data): Likewise.
	(desc_one_bound): Likewise.
	* eval.c (structop_base_operation::evaluate_funcall): Pass
	gdb::array_view, not a gdb::array_view* to value_struct_elt.
	(eval_op_structop_struct): Use '{}' instead of NULL to indicate
	an empty gdb::optional when calling value_struct_elt.
	(eval_op_structop_ptr): Likewise.
	* f-lang.c (fortran_structop_operation::evaluate): Likewise.
	* guile/scm-value.c (gdbscm_value_field): Likewise.
	* m2-lang.c (eval_op_m2_high): Likewise.
	(eval_op_m2_subscript): Likewise.
	* opencl-lang.c (opencl_structop_operation::evaluate): Likewise.
	* python/py-value.c (valpy_getitem): Likewise.
	* rust-lang.c (rust_val_print_str): Likewise.
	(rust_range): Likewise.
	(rust_subscript): Likewise.
	(eval_op_rust_structop): Likewise.
	(rust_aggregate_operation::evaluate): Likewise.
	* valarith.c (value_user_defined_op): Likewise.
	* valops.c (search_struct_method): Change parameter type, update
	function body accordingly, and update header comment.
	(value_struct_elt): Change parameter type, update function body
	accordingly.
	* value.h (value_struct_elt): Update declaration.
2021-06-25 20:43:06 +01:00
Marco Barisione
2f822da535 gdb: generate the prefix name for prefix commands on demand
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.
2021-05-12 11:19:22 +01:00
Andrew Burgess
0a703a4ced gdb/fortran: handle dynamic types within arrays and structures
This commit replaces this patch:

  https://sourceware.org/pipermail/gdb-patches/2021-January/174933.html

which was itself a replacement for this patch:

  https://sourceware.org/pipermail/gdb-patches/2020-July/170335.html

The motivation behind the original patch can be seen in the new test,
which currently gives a GDB session like this:

  (gdb) ptype var8
  type = Type type6
      PTR TO -> ( Type type2 :: ptr_1 )
      PTR TO -> ( Type type2 :: ptr_2 )
  End Type type6
  (gdb) ptype var8%ptr_2
  type = PTR TO -> ( Type type2
      integer(kind=4) :: spacer
      Type type1, allocatable :: t2_array(:)	<------ Issue 
  End Type type2 )
  (gdb) ptype var8%ptr_2%t2_array
  Cannot access memory at address 0x38		<------ Issue 
  (gdb)

Issue : Here we see the abstract dynamic type, rather than the
resolved concrete type.  Though in some cases the user might be
interested in the abstract dynamic type, I think that in most cases
showing the resolved concrete type will be of more use.  Plus, the
user can always figure out the dynamic type (by source code inspection
if nothing else) given the concrete type, but it is much harder to
figure out the concrete type given only the dynamic type.

Issue : In this example, GDB evaluates the expression in
EVAL_AVOID_SIDE_EFFECTS mode (due to ptype).  The value returned for
var8%ptr_2 will be a non-lazy, zero value of the correct dynamic
type.  However, when GDB asks about the type of t2_array this requires
GDB to access the value of var8%ptr_2 in order to read the dynamic
properties.  As this value was forced to zero (thanks to the use of
EVAL_AVOID_SIDE_EFFECTS) then GDB ends up accessing memory at a base
of zero plus some offset.

Both this patch, and my previous two attempts, have all tried to
resolve this problem by stopping EVAL_AVOID_SIDE_EFFECTS replacing the
result value with a zero value in some cases.

This new patch is influenced by how Ada handles its tagged typed.
There are plenty of examples in ada-lang.c, but one specific case is
ada_structop_operation::evaluate.  When GDB spots that we are dealing
with a tagged (dynamic) type, and we're in EVAL_AVOID_SIDE_EFFECTS
mode, then GDB re-evaluates the child operation in EVAL_NORMAL mode.

This commit handles two cases like this specifically for Fortran, a
new fortran_structop_operation, and the already existing
fortran_undetermined, which is where we handle array accesses.

In these two locations we spot when we are dealing with a dynamic type
and re-evaluate the child operation in EVAL_NORMAL mode so that we
are able to access the dynamic properties of the type.

The rest of this commit message is my attempt to record why my
previous patches failed.

To understand my second patch, and why it failed lets consider two
expressions, this Fortran expression:

  (gdb) ptype var8%ptr_2%t2_array	--<A>
  Operation: STRUCTOP_STRUCT		--(1)
   Operation: STRUCTOP_STRUCT		--(2)
    Operation: OP_VAR_VALUE		--(3)
     Symbol: var8
     Block: 0x3980ac0
    String: ptr_2
   String: t2_array

And this C expression:

  (gdb) ptype ptr && ptr->a == 3	--<B>
  Operation: BINOP_LOGICAL_AND		--(4)
   Operation: OP_VAR_VALUE		--(5)
    Symbol: ptr
    Block: 0x45a2a00
   Operation: BINOP_EQUAL		--(6)
    Operation: STRUCTOP_PTR		--(7)
     Operation: OP_VAR_VALUE		--(8)
      Symbol: ptr
      Block: 0x45a2a00
     String: a
    Operation: OP_LONG			--(9)
     Type: int
     Constant: 0x0000000000000003

In expression <A> we should assume that t2_array is of dynamic type.
Nothing has dynamic type in expression <B>.

This is how GDB currently handles expression <A>, in all cases,
EVAL_AVOID_SIDE_EFFECTS or EVAL_NORMAL, an OP_VAR_VALUE operation
always returns the real value of the symbol, this is not forced to a
zero value even in EVAL_AVOID_SIDE_EFFECTS mode.  This means that (3),
(5), and (8) will always return a real lazy value for the symbol.

However a STRUCTOP_STRUCT will always replace its result with a
non-lazy, zero value with the same type as its result.  So (2) will
lookup the field ptr_2 and create a zero value with that type.  In
this case the type is a pointer to a dynamic type.

Then, when we evaluate (1) to figure out the resolved type of
t2_array, we need to read the types dynamic properties.  These
properties are stored in memory relative to the objects base address,
and the base address is in var8%ptr_2, which we already figured out
has the value zero.  GDB then evaluates the DWARF expressions that
take the base address, add an offset and dereference.  GDB then ends
up trying to access addresses like 0x16, 0x8, etc.

To fix this, I proposed changing STRUCTOP_STRUCT so that instead of
returning a zero value we instead returned the actual value
representing the structure's field in the target.  My thinking was
that GDB would not try to access the value's contents unless it needed
it to resolve a dynamic type.  This belief was incorrect.

Consider expression <B>.  We already know that (5) and (8) will return
real values for the symbols being referenced.  The BINOP_LOGICAL_AND,
operation (4) will evaluate both of its children in
EVAL_AVOID_SIDE_EFFECTS in order to get the types, this is required
for C++ operator lookup.  This means that even if the value of (5)
would result in the BINOP_LOGICAL_AND returning false (say, ptr is
NULL), we still evaluate (6) in EVAL_AVOID_SIDE_EFFECTS mode.

Operation (6) will evaluate both children in EVAL_AVOID_SIDE_EFFECTS
mode, operation (9) is easy, it just returns a value with the constant
packed into it, but (7) is where the problem lies.  Currently in GDB
this STRUCTOP_STRUCT will always return a non-lazy zero value of the
correct type.

When the results of (7) and (9) are back in the BINOP_LOGICAL_AND
operation (6), the two values are passed to value_equal which performs
the comparison and returns a result.  Note, the two things compared
here are the immediate value (9), and a non-lazy zero value from (7).

However, with my proposed patch operation (7) no longer returns a zero
value, instead it returns a lazy value representing the actual value
in target memory.  When we call value_equal in (6) this code causes
GDB to try and fetch the actual value from target memory.  If `ptr` is
NULL then this will cause GDB to access some invalid address at an
offset from zero, this will most likely fail, and cause GDB to throw
an error instead of returning the expected type.

And so, we can now describe the problem that we're facing.  The way
GDB's expression evaluator is currently written we assume, when in
EVAL_AVOID_SIDE_EFFECTS mode, that any value returned from a child
operation can safely have its content read without throwing an
error.  If child operations start returning real values (instead of
the fake zero values), then this is simply not true.

If we wanted to work around this then we would need to rewrite almost
all operations (I would guess) so that EVAL_AVOID_SIDE_EFFECTS mode
does not cause evaluation of an operation to try and read the value of
a child operation.  As an example, consider this current GDB code from
eval.c:

  struct value *
  eval_op_equal (struct type *expect_type, struct expression *exp,
  	       enum noside noside, enum exp_opcode op,
  	       struct value *arg1, struct value *arg2)
  {
    if (binop_user_defined_p (op, arg1, arg2))
      {
        return value_x_binop (arg1, arg2, op, OP_NULL, noside);
      }
    else
      {
        binop_promote (exp->language_defn, exp->gdbarch, &arg1, &arg2);
        int tem = value_equal (arg1, arg2);
        struct type *type = language_bool_type (exp->language_defn,
  					      exp->gdbarch);
        return value_from_longest (type, (LONGEST) tem);
      }
  }

We could change this function to be this:

  struct value *
  eval_op_equal (struct type *expect_type, struct expression *exp,
  	       enum noside noside, enum exp_opcode op,
  	       struct value *arg1, struct value *arg2)
  {
    if (binop_user_defined_p (op, arg1, arg2))
      {
        return value_x_binop (arg1, arg2, op, OP_NULL, noside);
      }
    else
      {
        struct type *type = language_bool_type (exp->language_defn,
  					      exp->gdbarch);
        if (noside == EVAL_AVOID_SIDE_EFFECTS)
  	  return value_zero (type, VALUE_LVAL (arg1));
        else
  	{
  	  binop_promote (exp->language_defn, exp->gdbarch, &arg1, &arg2);
  	  int tem = value_equal (arg1, arg2);
  	  return value_from_longest (type, (LONGEST) tem);
  	}
      }
  }

Now we don't call value_equal unless we really need to.  However, we
would need to make the same, or similar change to almost all
operations, which would be a big task, and might not be a direction we
wanted to take GDB in.

So, for now, I'm proposing we go with the more targeted, Fortran
specific solution, that does the minimal required in order to
correctly resolve the dynamic types.

gdb/ChangeLog:

	* f-exp.h (class fortran_structop_operation): New class.
	* f-exp.y (exp): Create fortran_structop_operation instead of the
	generic structop_operation.
	* f-lang.c (fortran_undetermined::evaluate): Re-evaluate
	expression as EVAL_NORMAL if the result type was dynamic so we can
	extract the actual array bounds.
	(fortran_structop_operation::evaluate): New function.

gdb/testsuite/ChangeLog:

	* gdb.fortran/dynamic-ptype-whatis.exp: New file.
	* gdb.fortran/dynamic-ptype-whatis.f90: New file.
2021-04-07 17:19:46 +01:00
Felix Willgerodt
611aa09d99 gdb/fortran: Add 'LOC' intrinsic support.
LOC(X) returns the address of X as an integer:
https://gcc.gnu.org/onlinedocs/gfortran/LOC.html

Before:
(gdb) p LOC(r)
No symbol "LOC" in current context.

After:
(gdb) p LOC(r)
$1 = 0xffffdf48

gdb/ChangeLog:
2021-03-09  Felix Willgerodt  <felix.willgerodt@intel.com>

        * f-exp.h (eval_op_f_loc): Declare.
        (expr::fortran_loc_operation): New typedef.
        * f-exp.y (exp): Handle UNOP_FORTRAN_LOC after parsing an
        UNOP_INTRINSIC.
        (f77_keywords): Add LOC keyword.
        * f-lang.c (eval_op_f_loc): New function.
        * std-operator.def (UNOP_FORTRAN_LOC): New operator.

gdb/testsuite/ChangeLog:
2020-03-09  Felix Willgerodt  <felix.willgerodt@intel.com>

        * gdb.fortran/intrinsics.exp: Add LOC tests.
2021-03-09 11:34:55 +01:00
Andrew Burgess
eef32f5998 gdb/fotran: add support for the 'shape' keyword
Add support for the SHAPE keyword to GDB's Fortran expression parser.

gdb/ChangeLog:

	* f-exp.h (eval_op_f_array_shape): Declare.
	(fortran_array_shape_operation): New type.
	* f-exp.y (exp): Handle UNOP_FORTRAN_SHAPE after parsing
	UNOP_INTRINSIC.
	(f77_keywords): Add "shape" keyword.
	* f-lang.c (fortran_array_shape): New function.
	(eval_op_f_array_shape): New function.
	* std-operator.def (UNOP_FORTRAN_SHAPE): New operator.

gdb/testsuite/ChangeLog:

	* gdb.fortran/shape.exp: New file.
	* gdb.fortran/shape.f90: New file.
2021-03-09 09:51:23 +00:00
Andrew Burgess
7ba155b370 gdb/fortran: add support for 'SIZE' keyword
Add support for the 'SIZE' keyword to the Fortran expression parser.
This returns the number of elements either in an entire array (passing
a single argument to SIZE), or in a particular dimension of an
array (passing two arguments to SIZE).

At this point I have not added support for the optional third argument
to SIZE, which controls the exact integer type of the result.

gdb/ChangeLog:

	* f-exp.y (eval_op_f_array_size): Declare 1 and 2 argument forms
	of this function.
	(expr::fortran_array_size_1arg): New type.
	(expr::fortran_array_size_2arg): Likewise.
	* f-exp.y (exp): Handle FORTRAN_ARRAY_SIZE after parsing
	UNOP_OR_BINOP_INTRINSIC.
	(f77_keywords): Add "size" keyword.
	* f-lang.c (fortran_array_size): New function.
	(eval_op_f_array_size): New function, has a 1 arg and 2 arg form.
	* std-operator.def (FORTRAN_ARRAY_SIZE): New operator.

gdb/testsuite/ChangeLog:

	* gdb.fortran/size.exp: New file.
	* gdb.fortran/size.f90: New file.
2021-03-09 09:51:23 +00:00
Andrew Burgess
e14816a8ba gdb/fortran: add support for RANK keyword
gfortran supports the RANK keyword, see:

  https://gcc.gnu.org/onlinedocs/gfortran/RANK.html#RANK

this commit adds support for this keyword to GDB's Fortran expression
parser.

gdb/ChangeLog:

	* f-exp.h (eval_op_f_rank): Declare.
	(expr::fortran_rank_operation): New typedef.
	* f-exp.y (exp): Handle UNOP_FORTRAN_RANK after parsing an
	UNOP_INTRINSIC.
	(f77_keywords): Add "rank" keyword.
	* f-lang.c (eval_op_f_rank): New function.
	* std-operator.def (UNOP_FORTRAN_RANK): New operator.

gdb/testsuite/ChangeLog:

	* gdb.fortran/rank.exp: New file.
	* gdb.fortran/rank.f90: New file.
2021-03-09 09:45:18 +00:00
Tom Tromey
0b2b0b8220 Remove EVAL_SKIP
EVAL_SKIP was needed in the old expression implementation due to its
linearized tree structure.  This is not needed in the new
implementation, because it is trivial to not evaluate a subexpression.
This patch removes the last vestiges of EVAL_SKIP.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* value.h (eval_skip_value): Don't declare.
	* opencl-lang.c (eval_opencl_assign): Update.
	* m2-lang.c (eval_op_m2_high, eval_op_m2_subscript): Update.
	* f-lang.c (eval_op_f_abs, eval_op_f_mod, eval_op_f_ceil)
	(eval_op_f_floor, eval_op_f_modulo, eval_op_f_cmplx): Remove.
	* expression.h (enum noside) <EVAL_SKIP>: Remove.
	* expop.h (typeof_operation::evaluate)
	(decltype_operation::evaluate, unop_addr_operation::evaluate)
	(unop_sizeof_operation::evaluate, assign_operation::evaluate)
	(cxx_cast_operation::evaluate): Update.
	* eval.c (eval_skip_value): Remove.
	(eval_op_scope, eval_op_var_entry_value)
	(eval_op_func_static_var, eval_op_string, eval_op_objc_selector)
	(eval_op_concat, eval_op_ternop, eval_op_structop_struct)
	(eval_op_structop_ptr, eval_op_member, eval_op_add, eval_op_sub)
	(eval_op_binary, eval_op_subscript, eval_op_equal)
	(eval_op_notequal, eval_op_less, eval_op_gtr, eval_op_geq)
	(eval_op_leq, eval_op_repeat, eval_op_plus, eval_op_neg)
	(eval_op_complement, eval_op_lognot, eval_op_ind)
	(eval_op_memval, eval_op_preinc, eval_op_predec)
	(eval_op_postinc, eval_op_postdec, eval_op_type)
	(eval_binop_assign_modify, eval_op_objc_msgcall)
	(eval_multi_subscript, logical_and_operation::evaluate)
	(logical_or_operation::evaluate, array_operation::evaluate)
	(operation::evaluate_for_cast)
	(var_msym_value_operation::evaluate_for_cast)
	(var_value_operation::evaluate_for_cast): Update.
	* c-lang.c (c_string_operation::evaluate): Update.
	* c-exp.h (objc_nsstring_operation::evaluate)
	(objc_selector_operation::evaluate): Update.
	* ada-lang.c (ada_assign_operation::evaluate)
	(eval_ternop_in_range, ada_unop_neg, ada_unop_in_range)
	(ada_atr_size): Update.
2021-03-08 07:28:43 -07:00
Tom Tromey
1eaebe02cf Remove union exp_element
This removes union exp_element functions that either create such
elements or walk them.  struct expression no longer holds
exp_elements.  A couple of language_defn methods are also removed, as
they are obsolete.

Note that this patch also removes the print_expression code.  The only
in-tree caller of this was from dump_prefix_expression, which is only
called when expression debugging is enabled.  Implementing this would
involve a fair amount of code, and it seems to me that prefix dumping
is preferable anyway, as it is unambiguous.  So, I have not
reimplemented this feature.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* value.h (evaluate_subexp_with_coercion): Don't declare.
	* parse.c (exp_descriptor_standard): Remove.
	(expr_builder::expr_builder, expr_builder::release): Update.
	(expression::expression): Remove size_t parameter.
	(expression::~expression): Simplify.
	(expression::resize): Remove.
	(write_exp_elt, write_exp_elt_opcode, write_exp_elt_sym)
	(write_exp_elt_msym, write_exp_elt_block, write_exp_elt_objfile)
	(write_exp_elt_longcst, write_exp_elt_floatcst)
	(write_exp_elt_type, write_exp_elt_intern, write_exp_string)
	(write_exp_string_vector, write_exp_bitstring): Remove.
	* p-lang.h (class pascal_language) <opcode_print_table,
	op_print_tab>: Remove.
	* p-lang.c (pascal_language::op_print_tab): Remove.
	* opencl-lang.c (class opencl_language) <opcode_print_table>:
	Remove.
	* objc-lang.c (objc_op_print_tab): Remove.
	(class objc_language) <opcode_print_table>: Remove.
	* m2-lang.h (class m2_language) <opcode_print_table,
	op_print_tab>: Remove.
	* m2-lang.c (m2_language::op_print_tab): Remove.
	* language.h (struct language_defn) <post_parser, expression_ops,
	opcode_print_table>: Remove.
	* language.c (language_defn::expression_ops)
	(auto_or_unknown_language::opcode_print_table): Remove.
	* go-lang.h (class go_language) <opcode_print_table,
	op_print_tab>: Remove.
	* go-lang.c (go_language::op_print_tab): Remove.
	* f-lang.h (class f_language) <opcode_print_table>: Remove
	<op_print_tab>: Remove.
	* f-lang.c (f_language::op_print_tab): Remove.
	* expression.h (union exp_element): Remove.
	(struct expression): Remove size_t parameter from constructor.
	<resize>: Remove.
	<first_opcode>: Update.
	<nelts, elts>: Remove.
	(EXP_ELEM_TO_BYTES, BYTES_TO_EXP_ELEM): Remove.
	(evaluate_subexp_standard, print_expression, op_string)
	(dump_raw_expression): Don't declare.
	* expprint.c (print_expression, print_subexp)
	(print_subexp_funcall, print_subexp_standard, op_string)
	(dump_raw_expression, dump_subexp, dump_subexp_body)
	(dump_subexp_body_funcall, dump_subexp_body_standard): Remove.
	(dump_prefix_expression): Update.
	* eval.c (evaluate_subexp): Remove.
	(evaluate_expression, evaluate_type): Update.
	(evaluate_subexpression_type): Remove.
	(fetch_subexp_value): Remove "pc" parameter.  Update.
	(extract_field_op, evaluate_struct_tuple, evaluate_funcall)
	(evaluate_subexp_standard, evaluate_subexp_for_address)
	(evaluate_subexp_with_coercion, evaluate_subexp_for_sizeof)
	(evaluate_subexp_for_cast): Remove.
	(parse_and_eval_type): Update.
	* dtrace-probe.c (dtrace_probe::compile_to_ax): Update.
	* d-lang.c (d_op_print_tab): Remove.
	(class d_language) <opcode_print_table>: Remove.
	* c-lang.h (c_op_print_tab): Don't declare.
	* c-lang.c (c_op_print_tab): Remove.
	(class c_language, class cplus_language, class asm_language, class
	minimal_language) <opcode_print_table>: Remove.
	* breakpoint.c (update_watchpoint, watchpoint_check)
	(watchpoint_exp_is_const, watch_command_1): Update.
	* ax-gdb.h (union exp_element): Don't declare.
	* ax-gdb.c (const_var_ref, const_expr, maybe_const_expr)
	(gen_repeat, gen_sizeof, gen_expr_for_cast, gen_expr)
	(gen_expr_binop_rest): Remove.
	(gen_trace_for_expr, gen_eval_for_expr, gen_printf): Update.
	* ada-lang.c (ada_op_print_tab): Remove.
	(class ada_language) <post_parser, opcode_print_table>: Remove.
2021-03-08 07:28:41 -07:00
Tom Tromey
a99be8c199 Remove now-unused Fortran evaluator code
Now that the Fortran parser has switched to the new style, there is no
need for the old Fortran evaluation code.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* f-lang.h (class f_language) <expresssion_ops>: Remove.
	<exp_descriptor_tab>: Remove.
	* f-lang.c (fortran_value_subarray, evaluate_subexp_f)
	(operator_length_f, print_unop_subexp_f, print_binop_subexp_f)
	(print_subexp_f, dump_subexp_body_f, operator_check_f)
	(f_language::exp_descriptor_tab, fortran_prepare_argument):
	Remove.
2021-03-08 07:28:40 -07:00
Tom Tromey
f403a4e4a5 Implement fortran_allocated_operation
This implements the Fortran ALLOCATED intrinsic.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* f-exp.h (eval_op_f_allocated): Declare.
	(fortran_allocated_operation): New typedef.
	* f-lang.c (eval_op_f_allocated): No longer static.
2021-03-08 07:28:30 -07:00
Tom Tromey
eb4c927182 Implement Fortran associated operations
This implements the Fortran 1- and 2-argument "associated" operations.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* f-lang.c (eval_op_f_associated): New functions.
	* f-exp.h (fortran_associated_1arg, fortran_associated_2arg): New
	typedefs.
2021-03-08 07:28:30 -07:00
Tom Tromey
58a76c7264 Introduce classes for Fortran bound intrinsics
This adds class fortran_bound_1arg and fortran_bound_2arg, to
implement the Fortran lbound and ubound intrinsics.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* f-lang.c (fortran_bound_1arg::evaluate)
	(fortran_bound_2arg::evaluate): New methods.
	* f-exp.h (class fortran_bound_1arg, class fortran_bound_2arg):
	New.
2021-03-08 07:28:30 -07:00
Tom Tromey
2f98abe174 Introduce fortran_undetermined
This adds class fortran_undetermined, which implements
OP_F77_UNDETERMINED_ARGLIST.  fortran_range_operation is also added
here, as it is needed by fortran_undetermined.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* expop.h (class unop_addr_operation) <get_expression>: New
	method.
	* f-lang.c (fortran_undetermined::value_subarray)
	(fortran_undetermined::evaluate): New methods.
	(fortran_prepare_argument): New overload.
	* f-exp.h (class fortran_range_operation)
	(class fortran_undetermined): New classes.
2021-03-08 07:28:30 -07:00
Tom Tromey
9dcd3e2957 Implement several Fortran operations
This implements several straightforward Fortran operations, primarily
by reusing existing template classes.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* f-lang.c (eval_op_f_abs, eval_op_f_mod, eval_op_f_ceil)
	(eval_op_f_floor, eval_op_f_modulo, eval_op_f_cmplx)
	(eval_op_f_kind): No longer static.  Add "opcode" parameter.
	(evaluate_subexp_f): Update.
	* f-exp.h: New file.
2021-03-08 07:28:26 -07:00
Tom Tromey
9cbd1c2011 Split out eval_op_f_allocated
This splits out a helper function, eval_op_f_allocated, that will be
used in a later patch.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* f-lang.c (eval_op_f_allocated): New function.
	(evaluate_subexp_f): Use it.
2021-03-08 07:28:07 -07:00
Tom Tromey
3c18c49c63 Split out fortran_require_array
This splits out a helper function, fortran_require_array, that will be
used in a later patch.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* f-lang.c (fortran_require_array): New function.
	(evaluate_subexp_f): Use it.
2021-03-08 07:28:06 -07:00
Tom Tromey
216f6fcbef Split out eval_op_f_kind
This splits UNOP_FORTRAN_KIND into a new function for future use.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* f-lang.c (eval_op_f_kind): New function.
	(evaluate_subexp_f): Use it.
2021-03-08 07:28:06 -07:00
Tom Tromey
00f2db6f7d Split out eval_op_f_cmplx
This splits BINOP_FORTRAN_CMPLX into a new function for future use.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* f-lang.c (eval_op_f_cmplx): New function.
	(evaluate_subexp_f): Use it.
2021-03-08 07:28:06 -07:00
Tom Tromey
93b2b5fae2 Split out eval_op_f_modulo
This splits BINOP_FORTRAN_MODULO into a new function for future use.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* f-lang.c (eval_op_f_modulo): New function.
	(evaluate_subexp_f): Use it.
2021-03-08 07:28:06 -07:00
Tom Tromey
9f1a1f3c4f Split out eval_op_f_floor
This splits UNOP_FORTRAN_FLOOR into a new function for future use.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* f-lang.c (eval_op_f_floor): New function.
	(evaluate_subexp_f): Use it.
2021-03-08 07:28:06 -07:00
Tom Tromey
3dc41f3cdf Split out eval_op_f_ceil
This splits UNOP_FORTRAN_CEILING into a new function for future use.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* f-lang.c (eval_op_f_ceil): New function.
	(evaluate_subexp_f): Use it.
2021-03-08 07:28:05 -07:00
Tom Tromey
e08109f24b Split out eval_op_f_mod
This splits BINOP_MOD into a new function for future use.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* f-lang.c (eval_op_f_mod): New function.
	(evaluate_subexp_f): Use it.
2021-03-08 07:28:05 -07:00
Tom Tromey
cc05c68ee0 Split out eval_op_f_abs
This splits UNOP_ABS into a new function for future use.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* f-lang.c (eval_op_f_abs): New function.
	(evaluate_subexp_f): Use it.
2021-03-08 07:28:05 -07:00
Andrew Burgess
68337b8be3 gdb/fortran: don't access non-existent type fields
When attempting to call a Fortran function for which there is no debug
information we currently trigger undefined behaviour in GDB by
accessing non-existent type fields.

The reason is that in order to prepare the arguments, for a call to a
Fortran function, we need to know the type of each argument.  If the
function being called has no debug information then obviously GDB
doesn't know about the argument types and we should either give the
user an error or pick a suitable default.  What we currently do is
just assume the field exist and access undefined memory, which is
clearly wrong.

The reason GDB needs to know the argument type is to tell if the
argument is artificial or not, artificial arguments will be passed by
value while non-artificial arguments will be passed by reference.

An ideal solution for this problem would be to allow the user to cast
the function to the correct type, we already do this to some degree
with the return value, for example:

  (gdb) print some_func_ ()
  'some_func_' has unknown return type; cast the call to its declared return type
  (gdb) print (integer) some_func_ ()
  $1 = 1

But if we could extend this to allow casting to the full function
type, GDB could figure out from the signature what are real
parameters, and what are artificial parameters.  Maybe something like
this:

  (gdb) print ((integer () (integer, double)) some_other_func_ (1, 2.3)

Alas, right now the Fortran expression parser doesn't seem to support
parsing function signatures, and we certainly don't have support for
figuring out real vs artificial arguments from a signature.

Still, I think we can prevent GDB from accessing undefined memory and
provide a reasonable default behaviour.

In this commit I:

  - Only ask if the argument is artificial if the type of the argument
  is actually known.

  - Unknown arguments are assumed to be artificial and passed by
  value (non-artificial arguments are pass by reference).

  - If an artificial argument is prefixed with '&' by the user then we
  treat the argument as pass-by-reference.

With these three changes we avoid undefined behaviour in GDB, and
allow the user, in most cases, to get a reasonably natural default
behaviour.

gdb/ChangeLog:

	PR fortran/26155
	* f-lang.c (fortran_argument_convert): Delete declaration.
	(fortran_prepare_argument): New function.
	(evaluate_subexp_f): Move logic to new function
	fortran_prepare_argument.

gdb/testsuite/ChangeLog:

	PR fortran/26155
	* gdb.fortran/call-no-debug-func.f90: New file.
	* gdb.fortran/call-no-debug-prog.f90: New file.
	* gdb.fortran/call-no-debug.exp: New file.
2021-02-25 10:33:12 +00:00
Andrew Burgess
faeb9f13c1 gdb/fortran: add support for ASSOCIATED builtin
This commit adds support for the ASSOCIATED builtin to the Fortran
expression evaluator.  The ASSOCIATED builtin takes one or two
arguments.

When passed a single pointer argument GDB returns a boolean indicating
if the pointer is associated with anything.

When passed two arguments the second argument should either be some a
pointer could point at or a second pointer.

If the second argument is a pointer target, then the result from
associated indicates if the pointer is pointing at this target.

If the second argument is another pointer, then the result from
associated indicates if the two pointers are pointing at the same
thing.

gdb/ChangeLog:

	* f-exp.y (f77_keywords): Add 'associated'.
	* f-lang.c (fortran_associated): New function.
	(evaluate_subexp_f): Handle FORTRAN_ASSOCIATED.
	(operator_length_f): Likewise.
	(print_unop_or_binop_subexp_f): New function.
	(print_subexp_f): Make use of print_unop_or_binop_subexp_f for
	FORTRAN_ASSOCIATED, FORTRAN_LBOUND, and FORTRAN_UBOUND.
	(dump_subexp_body_f): Handle FORTRAN_ASSOCIATED.
	(operator_check_f): Likewise.
	* std-operator.def: Add FORTRAN_ASSOCIATED.

gdb/testsuite/ChangeLog:

	* gdb.fortran/associated.exp: New file.
	* gdb.fortran/associated.f90: New file.
2021-02-25 10:09:11 +00:00
Andrew Burgess
96df3e28b8 gdb/fortran: support ALLOCATED builtin
Add support for the ALLOCATED keyword to the Fortran expression
parser.

gdb/ChangeLog:

	* f-exp.y (f77_keywords): Add allocated.
	* f-lang.c (evaluate_subexp_f): Handle UNOP_FORTRAN_ALLOCATED.
	(operator_length_f): Likewise.
	(print_subexp_f): Likewise.
	(dump_subexp_body_f): Likewise.
	(operator_check_f): Likewise.
	* std-operator.def (UNOP_FORTRAN_ALLOCATED): New operator.

gdb/testsuite/ChangeLog:

	* gdb.fortran/allocated.exp: New file.
	* gdb.fortran/allocated.f90: New file.
2021-02-12 09:22:17 +00:00
Andrew Burgess
e92c8eb86d gdb/fortran: add parser support for lbound and ubound
Add support for the LBOUND and UBOUND built in functions to the
Fortran expression parser.

Both support taking one or two arguments.  A single argument, which
must be an array, returns an array containing all of the lower or
upper bound data.

When passed two arguments, the second argument is the dimension being
asked about.  In this case the result is a scalar containing the lower
or upper bound just for that dimension.

Some examples of usage taken from the new test:

  # Given:
  #   integer, dimension (-8:-1,-10:-2) :: neg_array
  #
  (gdb) p lbound (neg_array)
  $1 = (-8, -10)
  (gdb) p lbound (neg_array, 1)
  $3 = -8
  (gdb) p lbound (neg_array, 2)
  $5 = -10

gdb/ChangeLog:

	* f-exp.y (UNOP_OR_BINOP_INTRINSIC): New token.
	(exp): New pattern using UNOP_OR_BINOP_INTRINSIC.
	(one_or_two_args): New pattern.
	(f77_keywords): Add lbound and ubound.
	* f-lang.c (fortran_bounds_all_dims): New function.
	(fortran_bounds_for_dimension): New function.
	(evaluate_subexp_f): Handle FORTRAN_LBOUND and FORTRAN_UBOUND.
	(operator_length_f): Likewise.
	(print_subexp_f): Likewise.
	(dump_subexp_body_f): Likewise.
	(operator_check_f): Likewise.
	* std-operator.def (FORTRAN_LBOUND): Define.
	(FORTRAN_UBOUND): Define.

gdb/testsuite/ChangeLog:

	* gdb.fortran/lbound-ubound.F90: New file.
	* gdb.fortran/lbound-ubound.exp: New file.
2021-02-10 16:03:49 +00:00
Simon Marchi
8ee511afd8 gdb: rename get_type_arch to type::arch
... and update all users.

gdb/ChangeLog:

	* gdbtypes.h (get_type_arch): Rename to...
	(struct type) <arch>: ... this, update all users.

Change-Id: I0e3ef938a0afe798ac0da74a9976bbd1d082fc6f
2021-01-28 10:12:10 -05:00
Andrew Burgess
e343681375 gdb/fortran: Correct the lval type for array elements of internal vars
Since this commit:

  commit a5c641b57b
  Date:   Thu Oct 8 16:45:59 2020 +0100

      gdb/fortran: Add support for Fortran array slices at the GDB prompt

A bug was introduced into GDB.  Consider this Fortan array:

  integer, dimension (1:10) :: array
  array = 1

Now inside GDB:

  (gdb) set $var = array
  (gdb) set $var(1) = 2
  Left operand of assignment is not an lvalue.

The problem is that the new code for slicing Fortran arrays now does
not set the lval type correctly for arrays that are not in memory.
This is easily fixed by making use of value_from_component.

After this the above example behaves as you'd expect.

gdb/ChangeLog:

	* f-lang.c (fortran_value_subarray): Call value_from_component.

gdb/testsuite/ChangeLog:

	* gdb.fortran/intvar-array.exp: New file.
	* gdb.fortran/intvar-array.f90: New file.
2021-01-08 09:54:21 +00:00
Joel Brobecker
3666a04883 Update copyright year range in all GDB files
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.
2021-01-01 12:12:21 +04:00
Andrew Burgess
b7874836c3 gdb: avoid resolving dynamic properties for non-allocated arrays
In PR gdb/27059 an issue was discovered where GDB would sometimes
trigger undefined behaviour in the form of signed integer overflow.
The problem here is that GDB was reading random garbage from the
inferior memory space, assuming this data was valid, and performing
arithmetic on it.

This bug raises an interesting general problem with GDB's DWARF
expression evaluator, which is this:

We currently assume that the DWARF expressions being evaluated are
well formed, and well behaving.  As an example, this is the expression
that the bug was running into problems on, this was used as the
expression for a DW_AT_byte_stride of a DW_TAG_subrange_type:

	DW_OP_push_object_address;
	DW_OP_plus_uconst: 88;
	DW_OP_deref;
	DW_OP_push_object_address;
	DW_OP_plus_uconst: 32;
	DW_OP_deref;
	DW_OP_mul

Two values are read from the inferior and multiplied together.  GDB
should not assume that any value read from the inferior is in any way
sane, as such the implementation of DW_OP_mul should be guarding
against overflow and doing something semi-sane here.

However, it turns out that the original bug PR gdb/27059, is hitting a
more specific case, which doesn't require changes to the DWARF
expression evaluator, so I'm going to leave the above issue for
another day.

In the test mentioned in the bug GDB is actually trying to resolve the
dynamic type of a Fortran array that is NOT allocated.  A
non-allocated Fortran array is one that does not have any data
allocated for it yet, and even the upper and lower bounds of the array
are not yet known.

It turns out that, at least for gfortran compiled code, the data
fields that describe the byte-stride are not initialised until the
array is allocated.

This leads me to the following conclusion: GDB should not try to
resolve the bounds, or stride information for an array that is not
allocated (or not associated, a similar, but slightly different
Fortran feature).  Instead, each of these properties should be set to
undefined if the array is not allocated (or associated).

That is what this commit does.  There's a new flag that is passed
around during the dynamic array resolution.  When this flag is true
the dynamic properties are resolved using the DWARF expressions as
they currently are, but when this flag is false the expressions are
not evaluated, and instead the properties are set to undefined.

gdb/ChangeLog:

	PR gdb/27059
	* eval.c (evaluate_subexp_for_sizeof): Handle not allocated and
	not associated arrays.
	* f-lang.c (fortran_adjust_dynamic_array_base_address_hack): Don't
	adjust arrays that are not allocated/associated.
	* gdbtypes.c (resolve_dynamic_range): Update header comment.  Add
	new parameter which is used to sometimes set dynamic properties to
	undefined.
	(resolve_dynamic_array_or_string): Update header comment.  Add new
	parameter which is used to guard evaluating dynamic properties.
	Resolve allocated/associated properties first.

gdb/testsuite/ChangeLog:

	PR gdb/27059
	* gdb.dwarf2/dyn-type-unallocated.c: New file.
	* gdb.dwarf2/dyn-type-unallocated.exp: New file.
2020-12-24 16:45:40 +00:00