On openSUSE Tumbleweed I ran into:
...
(gdb) ptype outstring_func.part^M
No symbol "outstring_func" in current context.^M
(gdb) FAIL: gdb.fortran/call-no-debug.exp: ptype outstring_func.part
...
while on openSUSE Leap 15.2 I have instead:
...
(gdb) ptype string_func_^M
type = <unknown return type> ()^M
(gdb) PASS: gdb.fortran/call-no-debug.exp: ptype string_func_
...
The difference is caused by the result for "info function string_func", which
is this for the latter:
...
(gdb) info function string_func^M
All functions matching regular expression "string_func":^M
^M
Non-debugging symbols:^M
0x000000000040089c string_func_^M
...
but this for the former:
...
(gdb) info function string_func^M
All functions matching regular expression "string_func":^M
^M
Non-debugging symbols:^M
0x00000000004012bb string_func_^M
0x00007ffff7bac5b0 outstring_func.part^M
0x00007ffff7bb1a00 outstring_func.part^M
...
The extra symbols are part of glibc:
...
$ nm /lib64/libc.so.6 | grep string_func
00000000000695b0 t outstring_func.part.0
000000000006ea00 t outstring_func.part.0
...
If glibc debug info is installed, we get instead:
...
(gdb) info function string_func^M
All functions matching regular expression "string_func":^M
^M
File /usr/src/debug/glibc-2.33-9.1.x86_64/stdio-common/vfprintf-internal.c:^M
236: static int outstring_func(int, size_t, const unsigned int *, FILE *);^M
^M
File vfprintf-internal.c:^M
236: static int outstring_func(int, size_t, const unsigned char *, FILE *);^M
^M
Non-debugging symbols:^M
0x00000000004012bb string_func_^M
...
and the FAIL doesn't trigger.
Fix this by calling "info function string_func" before starting the exec, such
that only symbols of the exec are taken into account.
Tested on x86_64-linux.
gdb/testsuite/ChangeLog:
2021-09-01 Tom de Vries <tdevries@suse.de>
* gdb.fortran/call-no-debug.exp: Avoid shared lib symbols for
find_mangled_name calls.
Since commit 05b8577206 "gdb/fortran: Add type info of formal parameter for
clang" I see:
...
(gdb) ptype say_string^M
type = void (character*(*), integer(kind=4))^M
(gdb) FAIL: gdb.fortran/ptype-on-functions.exp: ptype say_string
...
The part of the commit causing the fail is:
...
gdb_test "ptype say_string" \
- "type = void \\(character\\*\\(\\*\\), integer\\(kind=\\d+\\)\\)"
+ "type = void \\(character\[^,\]+, $integer8\\)"
...
which fails to take into account that for gcc-7 and before, the type for
string length of a string argument is int, not size_t.
Fix this by allowing both $integer8 and $integer4.
Tested on x86_64-linux, with gcc-7 and gcc-10.
gdb/testsuite/ChangeLog:
2021-07-05 Tom de Vries <tdevries@suse.de>
* gdb.fortran/ptype-on-functions.exp: Allow both $integer8 and
$integer4 for size of string length.
Additional compiler generated formal parameter exist with clang and type
information for the same is added accordingly. Also few kind parameter
printing are removed which is not default for clang.
Note: More details about this kind parameter omission while printing can
be found with similar patch
commit 0a709cba00
Author Alok Kumar Sharma (alokkumar.sharma@amd.com)
gdb/testsuite/ChangeLog:
* gdb.fortran/ptype-on-functions.exp: Add type info of formal
parameter for clang. Also removed the kind parameter for clang.
It's a common mistake of mine to do:
...
set l [list "foo" "bar"]
set re [multi_line $l]
...
and to get "foo bar" while I was expecting "foo\r\nbar", which I get after
doing instead:
...
set re [multi_line {*}$l]
...
Detect this type of mistake by erroring out in multi_line when only one
argument is passed.
Tested on x86_64-linux.
gdb/testsuite/ChangeLog:
2021-06-08 Tom de Vries <tdevries@suse.de>
* lib/gdb.exp (multi_line): Require more than one argument.
* gdb.base/gdbinit-history.exp: Update multi_line call.
* gdb.base/jit-reader.exp: Remove multi_line call.
* gdb.fortran/dynamic-ptype-whatis.exp: Same.
As mentioned in the test case itself, depending on the fortran compiler
used, class member names used in the print commands and also output of
these print commands varies. Existing print commands and its output are
suited for gfortran, hence they were failing with clang compiler and test
case was modified accordingly for clang compiler.
gdb/testsuite/ChangeLog:
* gdb.base/class-allocatable-array.exp: Modified test for clang.
Breakpoint location is modified to "return" statement which is
outside the DO loop. Because the label 100 of DO loop should get
executed for each iteration as shared in this external link:
http://www-pnp.physics.ox.ac.uk/~gronbech/intfor/node18.html.
flang compiler is following this fortran standard, whereas gfortran
compiler is not following, hence the test case is passing with
gfortran and failing with flang. but to correct this gfortran
behavior, bug has been filed in bugzilla
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99816). As reported in
the bug, with gfortran, label 100 of DO loop is reached only after
the completion of the entire DO loop. Hence at label 100, all the
array elements are set and printing of array element a(2) succeeds.
whereas with flang, when we are at label 100 for first time, array
element a(2) is not yet set, only a(1) is set, hence moving the
breakpoint location to outside the DO loop, so that once we are
outside the DO loop, we can print any of the array elements. This
change in test case is done irrespective of any fortran compiler.
gdb/testsuite/ChangeLog:
* gdb.fortran/array-element.exp: Breakpoint location is modified.
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 #1
End Type type2 )
(gdb) ptype var8%ptr_2%t2_array
Cannot access memory at address 0x38 <------ Issue #2
(gdb)
Issue #1: 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 #2: 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.
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.
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.
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.
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.
This converts the Fortran parser to generate operations rather than
exp_elements. A couple of tests of expression debug dumping are
updated to follow the new output.
gdb/ChangeLog
2021-03-08 Tom Tromey <tom@tromey.com>
* f-exp.y: Create operations.
(f_language::parser): Update.
gdb/testsuite/ChangeLog
2021-03-08 Tom Tromey <tom@tromey.com>
* gdb.fortran/debug-expr.exp: Update tests.
In commit:
commit faeb9f13c1
Date: Wed Feb 24 12:50:00 2021 +0000
gdb/fortran: add support for ASSOCIATED builtin
A test was added that fails to process the trailing gdb prompt inside
a gdb_test_multiple call, this will cause a failure if the tests are
run with READ1=1, or randomly at other times depending on how the
expect buffers are read in.
Fixed by adding a -wrap argument.
gdb/testsuite/ChangeLog:
* gdb.fortran/associated.exp: Add missing '-wrap' argument.
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.
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.
gfortran supports .xor. as an alias for .neqv., see:
https://gcc.gnu.org/onlinedocs/gfortran/_002eXOR_002e-operator.html
this commit adds support for this operator to GDB.
gdb/ChangeLog:
* f-exp.y (fortran_operators): Add ".xor.".
gdb/testsuite/ChangeLog:
* gdb.fortran/dot-ops.exp (dot_operations): Test ".xor.".
When evaluating and expression containing UNOP_IND in mode
EVAL_AVOID_SIDE_EFFECTS, GDB currently (mostly) returns the result of
a call to value_zero meaning we get back an object with the correct
type, but its contents are all zero.
If the target type contains fields with dynamic type then in order to
resolve these dynamic fields GDB will need to read the value of the
field from within the parent object. In this case the field value
will be zero as a result of the call to value_zero mentioned above.
The idea behind EVAL_AVOID_SIDE_EFFECTS is to avoid the chance that
doing something like `ptype` will modify state within the target, for
example consider: ptype i++.
However, there is already precedence within GDB that sometimes, in
order to get accurate type results, we can't avoid reading from the
target, even when EVAL_AVOID_SIDE_EFFECTS is in effect. For example I
would point to eval.c:evaluate_var_value, the handling of OP_REGISTER,
the handling of value_x_unop in many places. I believe the Ada
expression evaluator also ignore EVAL_AVOID_SIDE_EFFECTS in some
cases.
I am therefor proposing that, in the case where a pointer points at a
dynamic type, we allow UNOP_IND to perform the actual indirection.
This allows accurate types to be displayed in more cases.
gdb/ChangeLog:
* eval.c (evaluate_subexp_standard): Call value_ind for points to
dynamic types in UNOP_IND.
gdb/testsuite/ChangeLog:
* gdb.fortran/pointer-to-pointer.exp: Additional tests.
In commit:
commit e92c8eb86d
Date: Tue Feb 9 15:46:13 2021 +0000
gdb/fortran: add parser support for lbound and ubound
When I created the test gdb/testsuite/gdb.fortran/lbound-ubound.exp, I
copied the script from a different file and failed to delete the test
description comment at the top (even though I added a new
description). Fixed in this commit.
gdb/testsuite/ChangeLog:
* gdb.fortran/lbound-ubound.exp: Remove old comment.
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.
When running test-case gdb.fortran/function-calls.exp with target board
unix/gdb:debug_flags=-gdwarf-5, I run into:
...
(gdb) PASS: gdb.fortran/function-calls.exp: \
p derived_types_and_module_calls::pass_cart(c)
p derived_types_and_module_calls::pass_cart_nd(c_nd)^M
^M
Program received signal SIGSEGV, Segmentation fault.^M
0x0000000000400f73 in derived_types_and_module_calls::pass_cart_nd \
(c=<error reading variable: Cannot access memory at address 0xc>) at \
function-calls.f90:130^M
130 pass_cart_nd = ubound(c%d,1,4)^M
The program being debugged was signaled while in a function called from GDB.^M
GDB has restored the context to what it was before the call.^M
To change this behavior use "set unwindonsignal off".^M
Evaluation of the expression containing the function^M
(derived_types_and_module_calls::pass_cart_nd) will be abandoned.^M
(gdb) FAIL: gdb.fortran/function-calls.exp: p
...
The problem originates in read_array_type, when reading a DW_TAG_array_type
with a dwarf-5 DW_TAG_generic_subrange child. This is not supported, and the
fallout of this is that rather than constructing a new array type, the code
proceeds to modify the element type.
Fix this conservatively by issuing a complaint and bailing out in
read_array_type when not being able to construct an array type, such that we
have:
...
(gdb) maint expand-symtabs function-calls.f90^M
During symbol reading: unable to find array range \
- DIE at 0xe1e [in module function-calls]^M
During symbol reading: unable to find array range \
- DIE at 0xe1e [in module function-calls]^M
(gdb) KFAIL: gdb.fortran/function-calls.exp: no complaints in srcfile \
(PRMS: symtab/27388)
...
Tested on x86_64-linux.
gdb/ChangeLog:
2021-02-09 Tom de Vries <tdevries@suse.de>
PR symtab/27341
* dwarf2/read.c (read_array_type): Return NULL when not being able to
construct an array type. Add assert to ensure that element_type is
not being modified.
gdb/testsuite/ChangeLog:
2021-02-09 Tom de Vries <tdevries@suse.de>
PR symtab/27341
* lib/gdb.exp (with_complaints): New proc, factored out of ...
(gdb_load_no_complaints): ... here.
* gdb.fortran/function-calls.exp: Add test-case.
When an executable contains an index such as a .gdb_index or .debug_names
section, gdb ignores the DW_AT_subprogram attribute.
This problem has been filed as PR symtab/24549.
Add KFAILs for this PR in test-cases gdb.dwarf2/main-subprogram.exp and
gdb.fortran/mixed-lang-stack.exp.
Tested on x86_64-linux.
gdb/testsuite/ChangeLog:
2021-02-05 Tom de Vries <tdevries@suse.de>
* gdb.dwarf2/main-subprogram.exp: Add KFAIL for PR symtab/24549.
* gdb.fortran/mixed-lang-stack.exp: Same.
After commit:
commit 10f92414d6
Date: Fri Jan 15 12:14:45 2021 +0100
[gdb/testsuite] Fix gdb.fortran/array-slices.exp with -m32
Some test names now contain the addresses of variables from the
inferior. When running the test in different directories I'm seeing
slightly different values for the addresses. This makes comparing
test results between directories harder than it needs to be.
This commit just gives the tests a descriptive name without including
the addresses.
gdb/testsuite/ChangeLog:
* gdb.fortran/array-slices.exp (run_test): Avoid including
addresses in test names.
When running test-case gdb.fortran/array-slices.exp with target board
unix/-m32, we run into:
...
(gdb) print /x &array4d^M
$69 = 0xffffb620^M
(gdb) print /x (&array4d) + sizeof (array4d)^M
$70 = 0x95c620^M
(gdb) FAIL: gdb.fortran/array-slices.exp: repack=on: test 9: check sizes match
...
The expressions calculate the start and end of an array, but the calculation
of the end expression has an unexpected result (given that it lies before the
start of the array). By printing "sizeof (array4d)" as a separate
expression:
...
(gdb) print /x sizeof (array4d)
$1 = 0xc40
...
it becomes clear we expected to get 0xffffb620 + 0xc40 == 0xffffc260 instead.
The problem is that using the '&' returns a pointer type:
...
(gdb) p &array4d
$5 = (PTR TO -> ( integer(kind=4) (-3:3,7:10,-3:3,-10:-7) )) 0xffffbe00
...
which has the consequence that the addition is done as pointer arithmetic.
Fix this by using the result of "print /x &array4d" instead of &array4d in the
addition.
Tested on x86_64-linux.
gdb/testsuite/ChangeLog:
2021-01-15 Tom de Vries <tdevries@suse.de>
PR testsuite/26997
* gdb.fortran/array-slices.exp (run_test): Avoid pointer arithmetic
when adding sizeof.
Consider this GDB session:
(gdb) set language fortran
(gdb) set debug expression 1
(gdb) p .TRUE.
Dump of expression @ 0x4055d90, before conversion to prefix form:
Language fortran, 3 elements, 16 bytes each.
Index Opcode Hex Value String Value
0 OP_BOOL 79 O...............
1 BINOP_ADD 1 ................
2 OP_BOOL 79 O...............
Dump of expression @ 0x4055d90, after conversion to prefix form:
Expression: `TRUE'
Language fortran, 3 elements, 16 bytes each.
0 OP_BOOL Unknown format
1 BINOP_ADD
2 OP_BOOL Unknown format
3 OP_NULL Unknown format
$1 = .TRUE.
The final dump of the OP_BOOL is completely wrong. After this patch
we now get:
(gdb) set language fortran
(gdb) set debug expression 1
(gdb) p .TRUE.
Dump of expression @ 0x2d07470, before conversion to prefix form:
Language fortran, 3 elements, 16 bytes each.
Index Opcode Hex Value String Value
0 OP_BOOL 79 O...............
1 BINOP_ADD 1 ................
2 OP_BOOL 79 O...............
Dump of expression @ 0x2d07470, after conversion to prefix form:
Expression: `TRUE'
Language fortran, 3 elements, 16 bytes each.
0 OP_BOOL TRUE
$1 = .TRUE.
Much better. I added a test for this into the Fortran testsuite.
gdb/ChangeLog:
* expprint.c (dump_subexp_body_standard): Handle OP_BOOL.
gdb/testsuite/ChangeLog:
* gdb.fortran/debug-expr.exp: Add new tests.
Fortran supports symbol based comparison operators as well as the
classic text based comparison operators, so we have:
Text | Symbol
Operator | Operator
---------|---------
.eq. | ==
.ne. | /=
.le. | <=
.ge. | >=
.gt. | >
.lt. | <
This commit adds the symbol based operators as well as some tests.
gdb/ChangeLog:
* f-exp.y (dot_ops): Rename to...
(fortran_operators): ...this. Add a header comment. Add symbol
based operators.
(yylex): Update to use fortran_operators not dot_ops. Remove
special handling for '**', this is now included in
fortran_operators.
gdb/testsuite/ChangeLog:
* gdb.fortran/dot-ops.exp: Add new tests.
Consider this Fortran type:
type :: some_type
integer, allocatable :: array_one (:,:)
integer :: a_field
integer, allocatable :: array_two (:,:)
end type some_type
And a variable declared:
type(some_type) :: some_var
Now within GDB we try this:
(gdb) set $a = some_var
(gdb) p $a
$1 = ( array_one =
../../src/gdb/value.c:3968: internal-error: Unexpected lazy value type.
Normally, when an internalvar ($a in this case) is created, it is
non-lazy, the value is immediately copied out of the inferior into
GDB's memory.
When printing the internalvar ($a) GDB will extract each field in
turn, so in this case `array_one`. As the original internalvar is
non-lazy then the extracted field will also be non-lazy, with its
contents immediately copied from the parent internalvar.
However, when the field has a dynamic type this is not the case, in
value_primitive_field we see that any field with dynamic type is
always created lazy. Further, the content of this field will usually
not have been captured in the contents buffer of the original value, a
field with dynamic location is effectively a pointer value contained
within the parent value, with rules in the DWARF for how to
dereference the pointer.
So, we end up with a lazy lval_internalvar_component representing a
field within an lval_internalvar. This eventually ends up in
value_fetch_lazy, which currently does not support
lval_internalvar_component, and we see the error above.
My original plan for how to handle this involved extending
value_fetch_lazy to handle lval_internalvar_component. However, when
I did this I ran into another error:
(gdb) set $a = some_var
(gdb) p $a
$1 = ( array_one = ((1, 1) (1, 1) (1, 1)), a_field = 5, array_two = ((0, 0, 0) (0, 0, 0)) )
(gdb) p $a%array_one
$2 = ((1, 1) (1, 1) (1, 1))
(gdb) p $a%array_one(1,1)
../../src/gdb/value.c:1547: internal-error: void set_value_address(value*, CORE_ADDR): Assertion `value->lval == lval_memory' failed.
The problem now is inside set_value_component_location, where we
attempt to set the address for a component if the original parent
value has a dynamic location. GDB does not expect to ever set the
address on anything other than an lval_memory value (which seems
reasonable).
In order to resolve this issue I initially thought about how an
internalvar should "capture" the value of a program variable at the
moment the var is created. In an ideal world (I think) GDB would be
able to do this even for values with dynamic type. So in our above
example doing `set $a = some_var` would capture the content of
'some_var', but also the content of 'array_one', and also 'array_two',
even though these content regions are not contained within the region
of 'some_var'.
Supporting this would require GDB values to be able to carry around
multiple non-contiguous regions of memory as content in some way,
which sounds like a pretty huge change to a core part of GDB.
So, I wondered if there was some other solution that wouldn't require
such a huge change.
What if values with a dynamic location were though of like points with
automatic dereferencing? Given this C structure:
struct foo_t {
int *val;
}
struct foo_t my_foo;
Then in GDB:
(gdb) $a = my_foo
We would expect GDB to capture the pointer value in '$a', but not the
value pointed at by the pointer. So maybe it's not that unreasonable
to think that given a dynamically typed field GDB will capture the
address of the content, but not the actual content itself.
That's what this patch does.
The approach is to catch this case in set_value_component_location.
When we create a component location (of an lval_internalvar) that has
a dynamic data location, the lval_internalvar_component is changed
into an lval_memory. After this, both of the above issues are
resolved. In the first case, the lval_memory is still lazy, but
value_fetch_lazy knows how to handle that. In the second case, when
we access an element of the array we are now accessing an element of
an lval_memory, not an lval_internalvar_component, and calling
set_value_address on an lval_memory is fine.
gdb/ChangeLog:
* value.c (set_value_component_location): Adjust the VALUE_LVAL
for internalvar components that have a dynamic location.
gdb/testsuite/ChangeLog:
* gdb.fortran/intvar-dynamic-types.exp: New file.
* gdb.fortran/intvar-dynamic-types.f90: New file.
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.
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.
This commit brings array slice support to GDB.
WARNING: This patch contains a rather big hack which is limited to
Fortran arrays, this can be seen in gdbtypes.c and f-lang.c. More
details on this below.
This patch rewrites two areas of GDB's Fortran support, the code to
extract an array slice, and the code to print an array.
After this commit a user can, from the GDB prompt, ask for a slice of
a Fortran array and should get the correct result back. Slices can
(optionally) have the lower bound, upper bound, and a stride
specified. Slices can also have a negative stride.
Fortran has the concept of repacking array slices. Within a compiled
Fortran program if a user passes a non-contiguous array slice to a
function then the compiler may have to repack the slice, this involves
copying the elements of the slice to a new area of memory before the
call, and copying the elements back to the original array after the
call. Whether repacking occurs will depend on which version of
Fortran is being used, and what type of function is being called.
This commit adds support for both packed, and unpacked array slicing,
with the default being unpacked.
With an unpacked array slice, when the user asks for a slice of an
array GDB creates a new type that accurately describes where the
elements of the slice can be found within the original array, a
value of this type is then returned to the user. The address of an
element within the slice will be equal to the address of an element
within the original array.
A user can choose to select packed array slices instead using:
(gdb) set fortran repack-array-slices on|off
(gdb) show fortran repack-array-slices
With packed array slices GDB creates a new type that reflects how the
elements of the slice would look if they were laid out in contiguous
memory, allocates a value of this type, and then fetches the elements
from the original array and places then into the contents buffer of
the new value.
One benefit of using packed slices over unpacked slices is the memory
usage, taking a small slice of N elements from a large array will
require (in GDB) N * ELEMENT_SIZE bytes of memory, while an unpacked
array will also include all of the "padding" between the
non-contiguous elements. There are new tests added that highlight
this difference.
There is also a new debugging flag added with this commit that
introduces these commands:
(gdb) set debug fortran-array-slicing on|off
(gdb) show debug fortran-array-slicing
This prints information about how the array slices are being built.
As both the repacking, and the array printing requires GDB to walk
through a multi-dimensional Fortran array visiting each element, this
commit adds the file f-array-walk.h, which introduces some
infrastructure to support this process. This means the array printing
code in f-valprint.c is significantly reduced.
The only slight issue with this commit is the "rather big hack" that I
mentioned above. This hack allows us to handle one specific case,
array slices with negative strides. This is something that I don't
believe the current GDB value contents model will allow us to
correctly handle, and rather than rewrite the value contents code
right now, I'm hoping to slip this hack in as a work around.
The problem is that, as I see it, the current value contents model
assumes that an object base address will be the lowest address within
that object, and that the contents of the object start at this base
address and occupy the TYPE_LENGTH bytes after that.
( We do have the embedded_offset, which is used for C++ sub-classes,
such that an object can start at some offset from the content buffer,
however, the assumption that the object then occupies the next
TYPE_LENGTH bytes is still true within GDB. )
The problem is that Fortran arrays with a negative stride don't follow
this pattern. In this case the base address of the object points to
the element with the highest address, the contents of the array then
start at some offset _before_ the base address, and proceed for one
element _past_ the base address.
As the stride for such an array would be negative then, in theory the
TYPE_LENGTH for this type would also be negative. However, in many
places a value in GDB will degrade to a pointer + length, and the
length almost always comes from the TYPE_LENGTH.
It is my belief that in order to correctly model this case the value
content handling of GDB will need to be reworked to split apart the
value's content buffer (which is a block of memory with a length), and
the object's in memory base address and length, which could be
negative.
Things are further complicated because arrays with negative strides
like this are always dynamic types. When a value has a dynamic type
and its base address needs resolving we actually store the address of
the object within the resolved dynamic type, not within the value
object itself.
In short I don't currently see an easy path to cleanly support this
situation within GDB. And so I believe that leaves two options,
either add a work around, or catch cases where the user tries to make
use of a negative stride, or access an array with a negative stride,
and throw an error.
This patch currently goes with adding a work around, which is that
when we resolve a dynamic Fortran array type, if the stride is
negative, then we adjust the base address to point to the lowest
address required by the array. The printing and slicing code is aware
of this adjustment and will correctly slice and print Fortran arrays.
Where this hack will show through to the user is if they ask for the
address of an array in their program with a negative array stride, the
address they get from GDB will not match the address that would be
computed within the Fortran program.
gdb/ChangeLog:
* Makefile.in (HFILES_NO_SRCDIR): Add f-array-walker.h.
* NEWS: Mention new options.
* f-array-walker.h: New file.
* f-lang.c: Include 'gdbcmd.h' and 'f-array-walker.h'.
(repack_array_slices): New static global.
(show_repack_array_slices): New function.
(fortran_array_slicing_debug): New static global.
(show_fortran_array_slicing_debug): New function.
(value_f90_subarray): Delete.
(skip_undetermined_arglist): Delete.
(class fortran_array_repacker_base_impl): New class.
(class fortran_lazy_array_repacker_impl): New class.
(class fortran_array_repacker_impl): New class.
(fortran_value_subarray): Complete rewrite.
(set_fortran_list): New static global.
(show_fortran_list): Likewise.
(_initialize_f_language): Register new commands.
(fortran_adjust_dynamic_array_base_address_hack): New function.
* f-lang.h (fortran_adjust_dynamic_array_base_address_hack):
Declare.
* f-valprint.c: Include 'f-array-walker.h'.
(class fortran_array_printer_impl): New class.
(f77_print_array_1): Delete.
(f77_print_array): Delete.
(fortran_print_array): New.
(f_value_print_inner): Update to call fortran_print_array.
* gdbtypes.c: Include 'f-lang.h'.
(resolve_dynamic_type_internal): Call
fortran_adjust_dynamic_array_base_address_hack.
gdb/testsuite/ChangeLog:
* gdb.fortran/array-slices-bad.exp: New file.
* gdb.fortran/array-slices-bad.f90: New file.
* gdb.fortran/array-slices-sub-slices.exp: New file.
* gdb.fortran/array-slices-sub-slices.f90: New file.
* gdb.fortran/array-slices.exp: Rewrite tests.
* gdb.fortran/array-slices.f90: Rewrite tests.
* gdb.fortran/vla-sizeof.exp: Correct expected results.
gdb/doc/ChangeLog:
* gdb.texinfo (Debugging Output): Document 'set/show debug
fortran-array-slicing'.
(Special Fortran Commands): Document 'set/show fortran
repack-array-slices'.
Add support for tab-completion on Fortran field names. Consider this
test case:
program test
type my_type
integer :: field_a
integer :: other_field
integer :: last_field
end type my_type
type(my_type) :: var
print *, var
end program test
And the GDB session before this patch:
(gdb) start
...
(gdb) p var% <- Trigger TAB completion here.
Display all 200 possibilities? (y or n) n
(gdb) p var%
And the GDB session with this patch:
(gdb) start
...
(gdb) p var% <- Trigger TAB completion here.
field_a last_field other_field
(gdb) p var%
The implementation for this is basically copied from c-exp.y, I
tweaked the parser patterns to be appropriate for Fortran, and it
"just worked".
gdb/ChangeLog:
PR cli/26879
* f-exp.y (COMPLETE): New token.
(exp): Two new rules for tab-completion.
(saw_name_at_eof): New static global.
(last_was_structop): Likewise.
(yylex): Set new variables, and return COMPLETE token at the end
of the input stream in some cases.
gdb/testsuite/ChangeLog:
PR cli/26879
* gdb.fortran/completion.exp: New file.
* gdb.fortran/completion.f90: New file.
Consider the following GDB session:
$ gdb
(gdb) set language c
(gdb) ptype void
type = void
(gdb) set language fortran
(gdb) ptype void
No symbol table is loaded. Use the "file" command.
(gdb)
With no symbol file loaded GDB and the language set to C GDB knows
about the type void, while when the language is set to Fortran GDB
doesn't know about the void, why is that?
In f-lang.c, f_language::language_arch_info, we do have this line:
lai->primitive_type_vector [f_primitive_type_void]
= builtin->builtin_void;
where we add the void type to the list of primitive types that GDB
should always know about, so what's going wrong?
It turns out that the primitive types are stored in a C style array,
indexed by an enum, so Fortran uses `enum f_primitive_types'. The
array is allocated and populated in each languages language_arch_info
member function. The array is allocated with an extra entry at the
end which is left as a NULL value, and this indicates the end of the
array of types.
Unfortunately for Fortran, a type is not assigned for each element in
the enum. As a result the final populated array has gaps in it, gaps
which are initialised to NULL, and so every time we iterate over the
list (for Fortran) we stop early, and never reach the void type.
This has been the case since 2007 when this functionality was added to
GDB in commit cad351d11d.
Obviously I could just fix Fortran by ensuring that either the enum is
trimmed, or we create types for the missing types. However, I think a
better approach would be to move to C++ data structures and removed
the fixed enum indexing into the array approach.
After this commit the primitive types are pushed into a vector, and
GDB just iterates over the vector in the obvious way when it needs to
hunt for a type. After this commit all the currently defined
primitive types can be found when the language is set to Fortran, for
example:
$ gdb
(gdb) set language fortran
(gdb) ptype void
type = void
(gdb)
A new test checks this functionality.
I didn't see any other languages with similar issues, but I could have
missed something.
gdb/ChangeLog:
* ada-exp.y (find_primitive_type): Make parameter const.
* ada-lang.c (enum ada_primitive_types): Delete.
(ada_language::language_arch_info): Update.
* c-lang.c (enum c_primitive_types): Delete.
(c_language_arch_info): Update.
(enum cplus_primitive_types): Delete.
(cplus_language::language_arch_info): Update.
* d-lang.c (enum d_primitive_types): Delete.
(d_language::language_arch_info): Update.
* f-lang.c (enum f_primitive_types): Delete.
(f_language::language_arch_info): Update.
* go-lang.c (enum go_primitive_types): Delete.
(go_language::language_arch_info): Update.
* language.c (auto_or_unknown_language::language_arch_info):
Update.
(language_gdbarch_post_init): Use obstack_new, use array indexing.
(language_string_char_type): Add header comment, call function in
language_arch_info.
(language_bool_type): Likewise
(language_arch_info::bool_type): Define.
(language_lookup_primitive_type_1): Delete.
(language_lookup_primitive_type): Rewrite as a templated function
to call function in language_arch_info, then instantiate twice.
(language_arch_info::type_and_symbol::alloc_type_symbol): Define.
(language_arch_info::lookup_primitive_type_and_symbol): Define.
(language_arch_info::lookup_primitive_type): Define twice with
different signatures.
(language_arch_info::lookup_primitive_type_as_symbol): Define.
(language_lookup_primitive_type_as_symbol): Rewrite to call a
member function in language_arch_info.
* language.h (language_arch_info): Complete rewrite.
(language_lookup_primitive_type): Make templated.
* m2-lang.c (enum m2_primitive_types): Delete.
(m2_language::language_arch_info): Update.
* opencl-lang.c (OCL_P_TYPE): Delete.
(enum opencl_primitive_types): Delete.
(opencl_type_data): Delete.
(builtin_opencl_type): Delete.
(lookup_opencl_vector_type): Update.
(opencl_language::language_arch_info): Update, lots of content
moved from...
(build_opencl_types): ...here. This function is now deleted.
(_initialize_opencl_language): Delete.
* p-lang.c (enum pascal_primitive_types): Delete.
(pascal_language::language_arch_info): Update.
* rust-lang.c (enum rust_primitive_types): Delete.
(rust_language::language_arch_info): Update.
gdb/testsuite/ChangeLog:
* gdb.fortran/types.exp: Add more tests.
In commit:
commit 6d81691950
CommitDate: Sat Sep 19 09:44:58 2020 +0100
gdb/fortran: Move Fortran expression handling into f-lang.c
A bug was introduced that broke GDB's ability to perform debug dumps
of expressions containing function calls. For example this would no
longer work:
(gdb) set debug expression 1
(gdb) print call_me (&val)
Dump of expression @ 0x4eced60, before conversion to prefix form:
Language c, 12 elements, 16 bytes each.
Index Opcode Hex Value String Value
0 OP_VAR_VALUE 40 (...............
1 OP_M2_STRING 79862864 P...............
2 unknown opcode: 224 79862240 ................
3 OP_VAR_VALUE 40 (...............
4 OP_VAR_VALUE 40 (...............
5 OP_RUST_ARRAY 79861600 `...............
6 UNOP_PREDECREMENT 79861312 @...............
7 OP_VAR_VALUE 40 (...............
8 UNOP_ADDR 61 =...............
9 OP_FUNCALL 46 ................
10 BINOP_ADD 1 ................
11 OP_FUNCALL 46 ................
Dump of expression @ 0x4eced60, after conversion to prefix form:
Expression: `call_me (&main::val, VAL(Aborted (core dumped)
The situation was even worse for Fortran function calls, or array
indexes, which both make use of the same expression opcode.
The problem was that in a couple of places the index into the
expression array was handled incorrectly causing GDB to interpret
elements incorrectly. These issues are fixed in this commit.
There are already some tests to check GDB when 'set debug expression
1' is set, these can be found in gdb.*/debug-expr.exp. Unfortunately
the cases above were not covered.
In this commit I have cleaned up all of the debug-expr.exp files a
little, there was a helper function that had clearly been copied into
each file, this is now moved into lib/gdb.exp.
I've added a gdb.fortran/debug-expr.exp test file, and extended
gdb.base/debug-expr.exp to cover the function call case.
gdb/ChangeLog:
* expprint.c (print_subexp_funcall): Increment expression position
after reading argument count.
* f-lang.c (print_subexp_f): Skip over opcode before calling
common function.
(dump_subexp_body_f): Likewise.
gdb/testsuite/ChangeLog:
* gdb.base/debug-expr.c: Add extra function to allow for an
additional test.
* gdb.base/debug-expr.exp (test_debug_expr): Delete, replace calls
to this proc with gdb_test_debug_expr. Add an extra test.
* gdb.cp/debug-expr.exp (test_debug_expr): Delete, replace calls
to this proc with gdb_test_debug_expr, give the tests names
* gdb.dlang/debug-expr.exp (test_debug_expr): Delete, replace
calls to this proc with gdb_test_debug_expr, give the tests names
* gdb.fortran/debug-expr.exp: New file.
* gdb.fortran/debug-expr.f90: New file.
* lib/gdb.exp (gdb_test_debug_expr): New proc.
With this commit GDB now understands the syntax of Fortran array
strides, a user can type an expression including an array stride, but
they will only get an error informing them that array strides are not
supported.
This alone is an improvement on what we had before in GDB, better to
give the user a helpful message that a particular feature is not
supported than to just claim a syntax error.
Before:
(gdb) p array (1:10:2, 2:10:2)
A syntax error in expression, near `:2, 2:10:2)'.
Now:
(gdb) p array (1:10:2, 2:10:2)
Fortran array strides are not currently supported
Later commits will allow GDB to handle array strides correctly.
gdb/ChangeLog:
* expprint.c (dump_subexp_body_standard): Print RANGE_HAS_STRIDE.
* expression.h (enum range_type): Add RANGE_HAS_STRIDE.
* f-exp.y (arglist): Allow for a series of subranges.
(subrange): Add cases for subranges with strides.
* f-lang.c (value_f90_subarray): Catch use of array strides and
throw an error.
* parse.c (operator_length_standard): Handle RANGE_HAS_STRIDE.
gdb/testsuite/ChangeLog:
* gdb.fortran/array-slices.exp: Add a new test.
Currently, GDB will only stop the backtrace at the main function if
there is a minimal symbol with the matching name. In Fortran programs
compiled with gfortran this is not the case. The main function is
present in the DWARF, and as marked as DW_AT_main_subprogram, but
there's no minimal symbol.
This commit extends `inside_main_func` to check the full symbols if no
matching minimal symbol is found.
There's an updated test case that covers this change.
gdb/ChangeLog:
* frame.c (inside_main_func): Check full symbols as well as
minimal symbols.
gdb/testsuite/ChangeLog:
* gdb.fortran/mixed-lang-stack.exp (run_tests): Update expected
output of backtrace.
This commit makes the whitespace usage when printing Fortran arrays
more consistent, and more inline with how we print C arrays.
Currently a 2 dimensional Fotran array is printed like this, I find
the marked whitespace unpleasant:
(( 1, 2, 3) ( 4, 5, 6) )
^ ^ ^
After this commit the same array is printed like this:
((1, 2, 3) (4, 5, 6))
Which seems more inline with how we print C arrays, in the case of C
arrays we don't add extra whitespace before the first element.
gdb/ChangeLog:
* f-valprint.c (f77_print_array_1): Adjust printing of whitespace
for arrays.
gdb/testsuite/ChangeLog:
* gdb.fortran/array-slices.exp: Update expected results.
* gdb.fortran/class-allocatable-array.exp: Likewise.
* gdb.fortran/multi-dim.exp: Likewise.
* gdb.fortran/vla-type.exp: Likewise.
* gdb.mi/mi-vla-fortran.exp: Likewise.
The tests in this script are driven from two lists of expected
results, one of the lists is missing some data so DejaGNU ends up
passing the empty string to gdb_test, which means the test always
passes.
This commit adds the missing expected results into the script. The
tests still pass so there's no change in the results, but we are now
actually checking GDB's behaviour.
gdb/testsuite/ChangeLog:
* gdb.fortran/array-slices.exp: Add missing message data.
In the test cases complex.exp,pointer-to-pointer.exp,vla-ptr-info.exp
fortran.exp routines are not used, which are to determine the type/kind
string. Due to this these test incorrectly fail for Flang.
Now test cases are modified to use fortran.exp routines. fortran.exp
file is modified to add absent routines fortran_complex8 and
fortran_complex16.
gdb/testsuite/ChangeLog
* lib/fortran.exp (fortran_complex8): New proc.
(fortran_complex16): New proc.
* gdb.fortran/complex.exp: Use routines from fortran.exp
* gdb.fortran/pointer-to-pointer.exp: Likewise.
* gdb.fortran/vla-ptr-info.exp: Likewise.
Currently, GDB is not able to set a breakpoint at subprogram post
prologue for flang generated binaries. This is due to clang having
two line notes one before and another after the prologue.
Now the end of prologue is determined using symbol table, which was
the way for clang generated binaries already. Since clang and flang
both share same back-end it is true for flang as well.
gdb/ChangeLog
* amd64-tdep.c (amd64_skip_prologue): Using symbol table
to find the end of prologue for flang compiled binaries.
* arm-tdep.c (arm_skip_prologue): Likewise.
* i386-tdep.c (i386_skip_prologue): Likewise.
* producer.c (producer_is_llvm): New function.
(producer_parsing_tests): Added new tests for clang/flang.
* producer.h (producer_is_llvm): New declaration.
gdb/testsuite/ChangeLog
* gdb.fortran/vla-type.exp: Skip commands not required for
the Flang compiled binaries after prologue fix.
In gdb.fortran/mixed-lang-stack.f90, we have fortran function mixed_func_1d:
...
subroutine mixed_func_1d(a, b, c, d, str)
use, intrinsic :: iso_c_binding, only: c_int, c_float, c_double
use, intrinsic :: iso_c_binding, only: c_float_complex
implicit none
integer(c_int) :: a
real(c_float) :: b
real(c_double) :: c
complex(c_float_complex) :: d
character(len=*) :: str
...
which we declare in C in gdb.fortran/mixed-lang-stack.c like this:
...
extern void mixed_func_1d_ (int *, float *, double *, complex float *,
char *, size_t);
...
The fortran string parameter str is passed as a char *, and an additional
argument str_ for the string length. The type used for the string length
argument is size_t, but for gcc 7 and earlier, the actual type is int
instead ( see
https://gcc.gnu.org/onlinedocs/gfortran/Argument-passing-conventions.html ).
Fix this by declaring the string length type depending on the gcc version:
...
#if !defined (__GNUC__) || __GNUC__ > 7
typedef size_t fortran_charlen_t;
#else
typedef int fortran_charlen_t;
...
Tested on x86_64-linux, with gcc-7 and gcc-8.
gdb/testsuite/ChangeLog:
2020-08-15 Tom de Vries <tdevries@suse.de>
* gdb.fortran/mixed-lang-stack.c (fortran_charlen_t): New type.
(mixed_func_1d_): Use fortran_charlen_t in decl.
When running test-case gdb.fortran/mixed-lang-stack.exp, it passes, but we
find in gdb.log:
...
(gdb) bt^M
...
#7 0x000000000040113c in mixed_func_1b (a=1, b=2, c=3, d=(4,5), \
e=<error reading variable: value requires 140737488341744 bytes, which \
is more than max-value-size>, g=..., _e=6) at mixed-lang-stack.f90:87^M
...
while a bit later in gdb.log, we have instead for the same frame (after
adding a gdb_test_no_output "set print frame-arguments all" to prevent
getting "e=..."):
...
(gdb) up^M
#7 0x000000000040113c in mixed_func_1b (a=1, b=2, c=3, d=(4,5), \
e='abcdef', g=( a = 1.5, b = 2.5 ), _e=6) at mixed-lang-stack.f90:87^M
...
The difference is that in the latter case, we print the frame while it's
selected, while in the former, it's not.
The problem is that while trying to resolve the dynamic type of e in
resolve_dynamic_type, we call dwarf2_evaluate_property with a frame == NULL
argument, and then use the selected frame as the context in which to evaluate
the dwarf property, effectively evaluating a DW_OP_fbreg operation in the
wrong frame context.
Fix this by temporarily selecting the frame of which we're trying to print the
arguments in print_frame_args, borrowing code from print_frame_local_vars that
was added to fix a similar issue in commit 16c3b12f19 "error/internal-error
printing local variable during "bt full".
Build and tested on x86_64-linux.
gdb/ChangeLog:
2020-08-15 Tom de Vries <tdevries@suse.de>
PR backtrace/26390
* stack.c (print_frame_args): Temporarily set the selected
frame to FRAME while printing the frame's arguments.
gdb/testsuite/ChangeLog:
2020-08-15 Tom de Vries <tdevries@suse.de>
PR backtrace/26390
* gdb.fortran/mixed-lang-stack.exp: Call bt with -frame-arguments all.
Update expected pattern.
When running test-case gdb.fortran/info-modules.exp with gfortran 4.8.5, I
get:
...
FAIL: gdb.fortran/info-modules.exp: info module functions: \
check for entry 'info-types.f90', '35', \
'void mod1::__copy_mod1_M1t1\(Type m1t1, Type m1t1\);'
FAIL: gdb.fortran/info-modules.exp: info module functions -m mod1: \
check for entry 'info-types.f90', '35', \
'void mod1::__copy_mod1_M1t1\(Type m1t1, Type m1t1\);'
FAIL: gdb.fortran/info-modules.exp: info module variables: \
check for entry 'info-types.f90', '(35)?', \
'Type m1t1 mod1::__def_init_mod1_M1t1;'
FAIL: gdb.fortran/info-modules.exp: info module variables: \
check for entry 'info-types.f90', '(35)?', \
'Type __vtype_mod1_M1t1 mod1::__vtab_mod1_M1t1;'
...
With gfortran 7.5.0, we have:
...
$ readelf -wi info-modules | egrep "DW_AT_name.*(copy|def_init|vtype)_mod1"
<286> DW_AT_name : __def_init_mod1_M1t1
<29f> DW_AT_name : __vtype_mod1_M1t1
<3de> DW_AT_name : __copy_mod1_M1t1
$
...
but with gfortran 4.8.5:
...
$ readelf -wi info-modules | egrep "DW_AT_name.*(copy|def_init|vtype)_mod1"
$
...
Fix this by allowing these module functions and variables to be missing.
Tested on x86_64-linux with gcc 4.8.5 and gcc 7.5.0.
gdb/testsuite/ChangeLog:
2020-07-30 Tom de Vries <tdevries@suse.de>
* lib/sym-info-cmds.exp (GDBInfoModuleSymbols::check_entry_1): Factor
out of ...
(GDBInfoModuleSymbols::check_entry): ... here.
(GDBInfoModuleSymbols::check_optional_entry): New proc.
* gdb.fortran/info-modules.exp: Use check_optional_entry for entries
related to __def_init_mod1_M1t1 / __vtype_mod1_M1t1 / __copy_mod1_M1t1.
When running test-case gdb.fortran/ptype-on-functions.exp with gfortran 4.8.5,
we run into:
...
(gdb) ptype some_module::get_number^M
type = integer(kind=4) (Type __class_some_module_Number)^M
(gdb) FAIL: gdb.fortran/ptype-on-functions.exp: ptype some_module::get_number
ptype some_module::set_number^M
type = void (Type __class_some_module_Number, integer(kind=4))^M
(gdb) FAIL: gdb.fortran/ptype-on-functions.exp: ptype some_module::set_number
...
The test-case pattern expects a "_t" suffix on "__class_some_module_Number".
The difference is caused by a gcc commit 073afca6884 'class.c
(gfc_build_class_symbol): Append "_t" to target class names to make the
generated type names unique' which has been present since gcc 4.9.0.
Fix the pattern by optionally matching the _t suffix.
Tested on x86_64-linux, with gfortran 4.8.5 and 7.5.0.
gdb/testsuite/ChangeLog:
2020-07-30 Tom de Vries <tdevries@suse.de>
* gdb.fortran/ptype-on-functions.exp: Make "_t" suffix on
"__class_some_module_Number_t" optional.
After dereferencing a pointer (in value_ind) or following a
reference (in coerce_ref) we call readjust_indirect_value_type to
"fixup" the type of the resulting value object.
This fixup handles cases relating to the type of the resulting object
being different (a sub-class) of the original pointers target type.
If we encounter a pointer to a dynamic type then after dereferencing a
pointer (in value_ind) the type of the object created will have had
its dynamic type resolved. However, in readjust_indirect_value_type,
we use the target type of the original pointer to "fixup" the type of
the resulting value. In this case, the target type will be a dynamic
type, so the resulting value object, once again has a dynamic type.
This then triggers an assertion later within GDB.
The solution I propose here is that we call resolve_dynamic_type on
the pointer's target type (within readjust_indirect_value_type) so
that the resulting value is not converted back to a dynamic type.
The test case is based on the original test in the bug report.
gdb/ChangeLog:
PR fortran/23051
PR fortran/26139
* valops.c (value_ind): Pass address to
readjust_indirect_value_type.
* value.c (readjust_indirect_value_type): Make parameter
non-const, and add extra address parameter. Resolve original type
before using it.
* value.h (readjust_indirect_value_type): Update function
signature and comment.
gdb/testsuite/ChangeLog:
PR fortran/23051
PR fortran/26139
* gdb.fortran/class-allocatable-array.exp: New file.
* gdb.fortran/class-allocatable-array.f90: New file.
* gdb.fortran/pointer-to-pointer.exp: New file.
* gdb.fortran/pointer-to-pointer.f90: New file.
When using test-case gdb.fortran/info-modules.exp with gcc 8.4.0, I run into:
...
FAIL: gdb.fortran/info-modules.exp: info module variables: check for entry \
'info-types.f90', '35', 'Type m1t1 mod1::__def_init_mod1_M1t1;'
FAIL: gdb.fortran/info-modules.exp: info module variables: check for entry \
'info-types.f90', '35', 'Type __vtype_mod1_M1t1 mod1::__vtab_mod1_M1t1;'
...
This is caused by this change in gdb output:
...
(gdb) info module variables
...
File gdb.fortran/info-types.f90:
-35: Type m1t1 mod1::__def_init_mod1_M1t1;
+ Type m1t1 mod1::__def_init_mod1_M1t1;
-35: Type __vtype_mod1_M1t1 mod1::__vtab_mod1_M1t1;
+ Type __vtype_mod1_M1t1 mod1::__vtab_mod1_M1t1;
21: real(kind=4) mod1::mod1_var_1;
22: integer(kind=4) mod1::mod1_var_2;
...
caused by a change in debug info.
Fix this by allowing those entries without line number.
Tested on x86_64-linux.
gdb/testsuite/ChangeLog:
2020-07-21 Tom de Vries <tdevries@suse.de>
* gdb.fortran/info-modules.exp (info module variables): Allow missing
line numbers for some variables.
It was pointed out that the recently added test
gdb.fortran/ptype-on-functions.exp fails on older versions of
gfortran. This is because the ABI for passing string lengths changed
from a 4-byte to 8-byte value (on some targets).
This change is documented here:
https://gcc.gnu.org/gcc-8/changes.html.
Character variables longer than HUGE(0) elements are now possible on
64-bit targets. Note that this changes the procedure call ABI for
all procedures with character arguments on 64-bit targets, as the
type of the hidden character length argument has changed. The hidden
character length argument is now of type INTEGER(C_SIZE_T).
This commit just relaxes the pattern to accept any size of integer for
the string length argument.
gdb/testsuite/ChangeLog:
* gdb.fortran/ptype-on-functions.exp: Make the result pattern more
generic.
After commit:
commit 8c2e4e0689
Date: Sun Jul 12 22:58:51 2020 -0400
gdb: add accessors to struct dynamic_prop
An existing bug was exposed in the Fortran type printing code. When
GDB is asked to print the type of a function that takes a dynamic
string argument GDB will try to read the upper bound of the string.
The read of the upper bound is written as:
if (type->bounds ()->high.kind () == PROP_UNDEFINED)
// Treat the upper bound as unknown.
else
// Treat the upper bound as known and constant.
However, this is not good enough. When printing a function type the
dynamic argument types will not have been resolved. As a result the
dynamic property is not PROP_UNDEFINED, but nor is it constant.
By rewriting this code to specifically check for the PROP_CONST case,
and treating all other cases as the upper bound being unknown we avoid
incorrectly treating the dynamic property as being constant.
gdb/ChangeLog:
* f-typeprint.c (f_type_print_base): Allow for dynamic types not
being resolved.
gdb/testsuite/ChangeLog:
* gdb.fortran/ptype-on-functions.exp: Add more tests.
* gdb.fortran/ptype-on-functions.f90: Likewise.
When running test-case gdb.fortran/nested-funcs-2.exp with target board
native-gdbserver, we have:
...
(gdb) call contains_keyword::subroutine_to_call()^M
(gdb) FAIL: gdb.fortran/nested-funcs-2.exp: src_prefix=0: nest_prefix=1: \
call contains_keyword::subroutine_to_call()
...
This is caused by the fact that we're trying to match inferior output using
gdb_test.
Fix this by using gdb_test_stdio instead.
Tested on x86_64-linux.
gdb/testsuite/ChangeLog:
2020-05-14 Tom de Vries <tdevries@suse.de>
* gdb.fortran/nested-funcs-2.exp: Use gdb_test_stdio to test inferior
output.
In gdb.fortran we have:
...
DUPLICATE: gdb.fortran/complex.exp: whatis $
DUPLICATE: gdb.fortran/complex.exp: whatis $
DUPLICATE: gdb.fortran/complex.exp: whatis $
DUPLICATE: gdb.fortran/complex.exp: whatis $
...
Fix this by using with_test_prefix.
Tested on x86_64-linux.
gdb/testsuite/ChangeLog:
2020-05-12 Tom de Vries <tdevries@suse.de>
* gdb.fortran/complex.exp: Use with_test_prefix.
