Trying to print the value of a string whose size is not known at
compile-time before it gets assigned a value can lead to the following
internal error:
(gdb) p my_str
$1 =
/[...]/utils.c:1089: internal-error: virtual memory exhausted.
What happens is that my_str is described as a reference to an array
type whose bounds are dynamic. During the read of that variable's
value (in default_read_var_value), we end up resolving dynamic types
which, for reference types, makes us also resolve the target of that
reference type. This means we resolve our variable to a reference
to an array whose bounds are undefined, and unfortunately very far
appart.
So, when we pass that value to ada-valprint, and in particular to
da_val_print_ref, we eventually try to allocate too large of a buffer
corresponding to the (bogus) size of our array, hence the internal
error.
This patch fixes the problem by adding a size_check before trying
to print the dereferenced value. To perform this check, a function
that was previously specific to ada-lang.c (check_size) gets
exported, and renamed to something less prone to name collisions
(ada_ensure_varsize_limit).
gdb/ChangeLog:
* ada-lang.h (ada_ensure_varsize_limit): Declare.
* ada-lang.c (check_size): Remove advance declaration.
(ada_ensure_varsize_limit): Renames check_size.
Replace calls to check_size by calls to ada_ensure_varsize_limit
throughout.
* ada-valprint.c (ada_val_print_ref): Add call to
ada_ensure_varsize_limit. Add comment explaining why.
gdb/testsuite/ChangeLog:
* gdb.ada/str_uninit: New testcase.
Python 3's print requires to use parentheses, so this patch adds them
where they were missing.
gdb/testsuite/ChangeLog:
* gdb.ada/py_range.exp: Add parentheses to calls to print.
* gdb.dwarf2/symtab-producer.exp: Same.
* gdb.gdb/python-interrupts.exp: Same.
* gdb.gdb/python-selftest.exp: Same.
* gdb.python/py-linetable.exp: Same.
* gdb.python/py-type.exp: Same.
* gdb.python/py-value-cc.exp: Same.
* gdb.python/py-value.exp: Same.
Consider the following variable declaration:
type Array_Type is array (Integer range <>) of Integer;
Var: Array_Type (0 .. -1);
"ptype var" prints the wrong upper bound for that array:
(gdb) ptype var
type = array (0 .. 4294967295) of integer
The debugging info for the type of variable "Var" is as follow:
<2><cf>: Abbrev Number: 13 (DW_TAG_structure_type)
<d0> DW_AT_name : foo__var___PAD
<3><db>: Abbrev Number: 14 (DW_TAG_member)
<dc> DW_AT_name : F
<e0> DW_AT_type : <0xa5>
This is just an artifact from code generation, which is just
a wrapper that we should ignore. The real type is the type of
field "F" in that PAD type, which is described as:
<2><a5>: Abbrev Number: 10 (DW_TAG_array_type)
<a6> DW_AT_name : foo__TvarS
<3><b6>: Abbrev Number: 11 (DW_TAG_subrange_type)
<b7> DW_AT_type : <0xc1>
<bb> DW_AT_lower_bound : 0
<bc> DW_AT_upper_bound : 0xffffffff
Trouble occurs because DW_AT_upper_bound is encoded using
a DW_FORM_data4, which is ambiguous regarding signedness.
In that case, dwarf2read.c::dwarf2_get_attr_constant_value
reads the value as unsigned, which is not what we want
in this case.
As it happens, we already have code dealing with this situation
in dwarf2read.c::read_subrange_type which checks whether
the subrange's type is signed or not, and if it is, fixes
the bound's value by sign-extending it:
if (high.kind == PROP_CONST
&& !TYPE_UNSIGNED (base_type) && (high.data.const_val & negative_mask))
high.data.const_val |= negative_mask;
Unfortunately, what happens in our case is that the base type
of the array's subrange type is marked as being unsigned, and
so we never get to apply the sign extension. Following the DWARF
trail, the range's base type is described as another subrange type...
<2><c1>: Abbrev Number: 12 (DW_TAG_subrange_type)
<c7> DW_AT_name : foo__TTvarSP1___XDLU_0__1m
<cb> DW_AT_type : <0x2d>
... whose base type is, (finally), a basic type (signed):
<1><2d>: Abbrev Number: 2 (DW_TAG_base_type)
<2e> DW_AT_byte_size : 4
<2f> DW_AT_encoding : 5 (signed)
<30> DW_AT_name : integer
The reason why GDB thinks that foo__TTvarSP1___XDLU_0__1m
(the base type of the array's range type) is an unsigned type
is found in gdbtypes.c::create_range_type. We consider that
a range type is unsigned iff its lower bound is >= 0:
if (low_bound->kind == PROP_CONST && low_bound->data.const_val >= 0)
TYPE_UNSIGNED (result_type) = 1;
That is normally sufficient, as one would expect the upper bound to
always be greater or equal to the lower bound. But Ada actually
allows the declaration of empty range types where the upper bound
is less than the lower bound. In this case, the upper bound is
negative, so we should not be marking the type as unsigned.
This patch fixes the issue by simply checking the upper bound as well
as the lower bound, and clears the range type's unsigned flag when
it is found to be constant and negative.
gdb/ChangeLog:
* gdbtypes.c (create_range_type): Unset RESULT_TYPE's
flag_unsigned if HIGH_BOUND is constant and negative.
gdb/testsuite/ChangeLog:
* gdb.ada/n_arr_bound: New testcase.
Tested on x86_64-linux.
Consider the following code which declares a variable A2 which
is an array of arrays of integers.
type Array2_First is array (24 .. 26) of Integer;
type Array2_Second is array (1 .. 2) of Array2_First;
A1 : Array1_Second := ((10, 11, 12), (13, 14, 15));
Trying to print the type of that variable currently yields:
(gdb) ptype A2
type = array (1 .. 2, 24 .. 26) of integer
This is not correct, as this is the description of a two-dimension
array, which is different from an array of arrays. The expected
output is:
(gdb) ptype a2
type = array (1 .. 2) of foo_n926_029.array2_first
GDB's struct type currently handles multi-dimension arrays the same
way arrays of arrays, where each dimension is stored as a sub-array.
The ada-valprint module considers that consecutive array layers
are in fact multi-dimension arrays. For array of arrays, a typedef
layer is introduced between the two arrays, creating a break between
each array type.
In our situation, A2 is a described as a typedef of an array type...
.uleb128 0x8 # (DIE (0x125) DW_TAG_variable)
.ascii "a2\0" # DW_AT_name
.long 0xfc # DW_AT_type
.uleb128 0x4 # (DIE (0xfc) DW_TAG_typedef)
.long .LASF5 # DW_AT_name: "foo__array2_second"
.long 0x107 # DW_AT_type
.uleb128 0x5 # (DIE (0x107) DW_TAG_array_type)
.long .LASF5 # DW_AT_name: "foo__array2_second"
.long 0xb4 # DW_AT_type
.uleb128 0x6 # (DIE (0x114) DW_TAG_subrange_type)
.long 0x11b # DW_AT_type
.byte 0x2 # DW_AT_upper_bound
.byte 0 # end of children of DIE 0x107
... whose element type is, as expected, a typedef to the sub-array
type:
.uleb128 0x4 # (DIE (0xb4) DW_TAG_typedef)
.long .LASF4 # DW_AT_name: "foo__array2_first"
.long 0xbf # DW_AT_type
.uleb128 0x9 # (DIE (0xbf) DW_TAG_array_type)
.long .LASF4 # DW_AT_name: "foo__array2_first"
.long 0xd8 # DW_AT_GNAT_descriptive_type
.long 0x1c5 # DW_AT_type
.uleb128 0xa # (DIE (0xd0) DW_TAG_subrange_type)
.long 0xf0 # DW_AT_type
.byte 0x18 # DW_AT_lower_bound
.byte 0x1a # DW_AT_upper_bound
.byte 0 # end of children of DIE 0xbf
The reason why things fails is that, during expression evaluation,
GDB tries to "fix" A1's type. Because the sub-array has a parallel
(descriptive) type (DIE 0xd8), GDB thinks that our array's index
type must be dynamic and therefore needs to be fixed. This in turn
causes the sub-array to be "fixed", which itself results in the
typedef layer to be stripped.
However, looking closer at the parallel type, we see...
.uleb128 0xb # (DIE (0xd8) DW_TAG_structure_type)
.long .LASF8 # DW_AT_name: "foo__array2_first___XA"
[...]
.uleb128 0xc # (DIE (0xe4) DW_TAG_member)
.long .LASF10 # DW_AT_name: "foo__Tarray2_firstD1___XDLU_24__26"
... that all it tells us is that the array bounds are 24 and 26,
which is already correctly provided by the array's DW_TAG_subrange_type
bounds, meaning that this parallel type is just redundant.
Parallel types in general are slowly being removed in favor of
standard DWARF constructs. But in the meantime, this patch kills
two birds with one stone:
1. It recognizes this situation where the XA type is useless,
and saves an unnecessary range-type fixing;
2. It fixes the issue at hand because ignoring the XA type results
in no type fixing being required, which allows the typedef layer
to be preserved.
gdb/ChangeLog:
* ada-lang.c (ada_is_redundant_range_encoding): New function.
(ada_is_redundant_index_type_desc): New function.
(to_fixed_array_type): Ignore parallel XA type if redundant.
gdb/testsuite/ChangeLog:
* gdb.ada/arr_arr: New testcase.
Tested on x86_64-linux.
... when that packed array is part of a discriminated record and
one of the bounds is a discriminant.
Consider the following code:
type FUNNY_CHAR_T is (NUL, ' ', '"', '#', [etc]);
type FUNNY_STR_T is array (POSITIVE range <>) of FUNNY_CHAR_T;
pragma PACK (FUNNY_STR_T);
type FUNNY_STRING_T (SIZE : NATURAL := 1) is
record
STR : FUNNY_STR_T (1 .. SIZE) := (others => '0');
LENGTH : NATURAL := 4;
end record;
TEST: FUNNY_STRING_T(100);
GDB is able to print the value of variable "test" and "test.str".
But not "test.str(1)":
(gdb) p test
$1 = (size => 100, str => (33 'A', nul <repeats 99 times>), length => 1)
(gdb) p test.str
$2 = (33 'A', nul <repeats 99 times>)
(gdb) p test.str(1)
object size is larger than varsize-limit
The problem occurs during the phase where we are trying to resolve
the expression subscript operation. On the one hand of the subscript
operator, we have the result of the evaluation of "test.str", which
is our packed array. We have the following code to handle packed
arrays in particular:
if (ada_is_constrained_packed_array_type
(desc_base_type (value_type (argvec[0]))))
argvec[0] = ada_coerce_to_simple_array (argvec[0]);
This eventually leads to a call to constrained_packed_array_type
to return the "simple array". This function relies on a parallel
___XA type, when available, to determine the bounds. In our case,
we find type...
failure__funny_string_t__T4b___XA"
... which has one field describing the bounds of our array as:
failure__funny_string_t__T3b___XDLU_1__size
The part that interests us is after the ___XD suffix or,
in other words: "LU_1__size". What this means in GNAT encoding
parlance is that the lower bound is 1, and that the upper bound
is the value of "size". "size" is our discriminant in this case.
Normally, we would access the record's discriminant in order to
get the upper bound's value, but we do not have that information,
here. We are in a mode where we are just trying to "fix" the type
without an actual value. This is what the call to to_fixed_range_type
is doing, and because the fix'ing fails, it ends up returning
the ___XDLU type unmodified as our index type.
This shouldn't be a problem, except that the later part of
constrained_packed_array_type then uses that index_type to
determine the array size, via a call to get_discrete_bounds.
The problem is that the upper bound of the ___XDLU type is
dynamic (in the DWARF sense) while get_discrete_bounds implicitly
assumes that the bounds are static, and therefore accesses
them using macros that assume the bounds values are constants:
case TYPE_CODE_RANGE:
*lowp = TYPE_LOW_BOUND (type);
*highp = TYPE_HIGH_BOUND (type);
This therefore returns a bogus value for the upper bound,
leading to an unexpectedly large size for our array, which
later triggers the varsize-limit guard we've seen above.
This patch avoids the problem by adding special handling
of dynamic range types. It also extends the documentation
of the constrained_packed_array_type function to document
what happens in this situation.
gdb/ChangeLog:
* ada-lang.c (constrained_packed_array_type): Set the length
of the return array as if both bounds where zero if that
returned array's index type is dynamic.
gdb/testsuite/ChangeLog:
* gdb.ada/pkd_arr_elem: New Testcase.
Tested on x86_64-linux.
When trying to evaluate an expression which adds a pointer and
an integral, the evaluation succeeds if the pointer is on
the left handside of the operator, but not when it is on the right
handside:
(gdb) p something'address + 0
$1 = (system.address) 0x613418 <pck.something>
(gdb) p 0 + something'address
Argument to arithmetic operation not a number or boolean.
Same issue when doing subtractions:
(gdb) p something'address - 0
$2 = (system.address) 0x613418 <pck.something>
(gdb) p 0 - something'address
Argument to arithmetic operation not a number or boolean.
This patch enhances the Ada expression evaluator to handle
these two situations.
gdb/ChangeLog:
* ada-lang.c (ada_evaluate_subexp) <BINOP_ADD>: Add handling
of the case where the second operand is a pointer.
<BINOP_SUB>: Likewise.
gdb/testsuite/ChangeLog:
* gdb.ada/addr_arith: New testcase.
Tested on x86_64-linux.
This add a testcases that verifies correct handling of dynamicity
for lower bounds of arrays.
gdb/testsuite/ChangeLog:
* gdb.ada/dyn_arrayidx: New testcase.
Given the following variable...
BT : Bounded := New_Bounded (Low => 1, High => 3);
... where type Bounded is defined as a simple unconstrained array:
type Bounded is array (Integer range <>) of Integer;
Creating a varobj for that variable, and immediately asking for
varobj updates, GDB says that our varobj changed types!
(gdb)
-var-create bt * bt
^done,name="bt",numchild="3",value="[3]",type="<ref> array (1 .. 3) of integer",has_more="0"
(gdb)
-var-update 1 *
^done,changelist=[{name="bt",value="[3]",in_scope="true",type_changed="true",new_type="<ref> array (1 .. 3) of integer",new_num_children="3",has_more="0"}]
The expected output for the -var-update command is, in this case:
(gdb)
-var-update 1 *
^done,changelist=[]
The problem occurs because the ada-varobj module does not handle
references, and while the references gets stripped when the varobj
gets created, it doesn't when computing varobj updates.
More specifically, when creating the varobj, varobj_create creates
a new value which is a reference to a TYPE_CODE_ARRAY. It then calls
install_new_value which calls coerce_ref with the following comment:
/* We are not interested in the address of references, and given
that in C++ a reference is not rebindable, it cannot
meaningfully change. So, get hold of the real value. */
if (value)
value = coerce_ref (value);
This leaves the varobj's type component still a ref, while
the varobj's value is now our array, without the ref. This explains
why the "value" field in the varobj indicates an array with 3 elements
"[3]" while the "type" field shows a ref to an array. Generally
speaking, most users have said that showing the ref was a useful
piece of information, so this patch is not touching this part.
Next, when the user issues the -var-update request, varobj_update
calls value_of_root to compute the varobj's new value as well as
determine whether the value's type has changed or not. What happens
in a nutshell is that it calls value_of_root_1 (which re-evaluates
the expression and returns the corresponding new value), finds that
the new value is not NULL, and thus asks whether it has mutated:
else if (varobj_value_has_mutated (var, value, value_type (value)))
This then indirectly delegates the determination to the language-specific
callback, which fails, because it does not handle references.
This patch fixes the issue by adjusting varobj_value_has_mutated to
expect references, and strip them when seen. This allows the various
language-specific implementations to remain unaware of references.
gdb/ChangeLog:
* varobj.c (varobj_value_has_mutated): If NEW_VALUE is
a reference, strip the reference layer before calling
the lang_ops value_has_mutated callback.
gdb/testsuite/ChangeLog:
* gdb.ada/mi_dyn_arr: New testcase.
The completion feature and other features on readline depend on the
readline library. However, readline library is not always used, for
example, running testsuite like
make check RUNTESTFLAGS="--host_board=local-remote-host"
the input stream is not a tty, and GDB doesn't use readline library
as a result.
This patch is to skip tests on completion and readline if
'show editing' is off, which means readline isn't used. Note that
some tests in gdb.base/completion.exp test command complete, which
isn't related to readline, so these tests aren't affected by readline
library. This patch also moves these tests up, run them
unconditionally, and run the rest if readline library is used.
gdb/testsuite:
2014-03-26 Yao Qi <yao@codesourcery.com>
* lib/gdb.exp (readline_is_used): New proc.
* gdb.base/completion.exp: Move tests on command complete up.
Skip the rest of tests if readline is not used.
* gdb.ada/complete.exp: Skp the test if readline is not
used.
* gdb.base/filesym.exp: Likewise.
* gdb.base/macscp.exp: Likewise.
* gdb.base/readline-ask.exp: Likewise.
* gdb.base/readline.exp: Likewise.
* gdb.python/py-cmd.exp: Likewise.
* gdb.trace/tfile.exp: Likewise.
When evaluating an expression, if it is of a tagged type, GDB reads
the tag in memory and deduces the full view. At parsing time, however,
this operation is done only in the case of OP_VAR_VALUE. ptype does
not go through a full evaluation of expressions so it may return some
odd results:
(gdb) print c.menu_name
$1 = 0x0
(gdb) ptype $
type = system.strings.string_access
(gdb) ptype c.menu_name
type = <void>
This change removes this peculiarity by extending the tag resolution
to UNOP_IND and STRUCTOP_STRUCT. As in the case of OP_VAR_VALUE, this
implies switching from EVAL_AVOID_SIDE_EFFECTS to EVAL_NORMAL when a
tagged type is dereferenced.
gdb/
* ada-lang.c (ada_evaluate_subexp): Resolve tagged types to
full view in the case of UNOP_IND and STRUCTOP_STRUCT.
gdb/testsuite/
* gdb.ada/tagged_access: New testcase.
With the test changed as in the patch, against current mainline, we get:
(gdb) PASS: gdb.ada/tasks.exp: info tasks before inserting breakpoint
break break_me task 1
Breakpoint 2 at 0x4030b0: file /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.ada/tasks/foo.adb, line 27.
(gdb) PASS: gdb.ada/tasks.exp: break break_me task 1
break break_me task 3
Note: breakpoint 2 also set at pc 0x4030b0.
Breakpoint 3 at 0x4030b0: file /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.ada/tasks/foo.adb, line 27.
(gdb) PASS: gdb.ada/tasks.exp: break break_me task 3
continue
Continuing.
[Switching to Thread 0x7ffff7dc7700 (LWP 27133)]
Breakpoint 2, foo.break_me () at /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.ada/tasks/foo.adb:27
27 null;
(gdb) FAIL: gdb.ada/tasks.exp: continue to breakpoint
info tasks
ID TID P-ID Pri State Name
1 63b010 48 Waiting on RV with 3 main_task
2 63bd80 1 48 Accept or Select Term task_list(1)
* 3 63f510 1 48 Accepting RV with 1 task_list(2)
4 642ca0 1 48 Accept or Select Term task_list(3)
(gdb) PASS: gdb.ada/tasks.exp: info tasks after hitting breakpoint
The breakpoint that caused a stop is breakpoint 3, but GDB end up
reporting (and running breakpoint commands of) "Breakpoint 2" instead.
The issue is that the bpstat_check_breakpoint_conditions logic of
"wrong thread" is missing the "wrong task" check. This is usually
harmless, because the thread hop code in infrun.c code that handles
wrong-task-hitting-breakpoint does check for task-specific breakpoints
(within breakpoint_thread_match):
/* Check if a regular breakpoint has been hit before checking
for a potential single step breakpoint. Otherwise, GDB will
not see this breakpoint hit when stepping onto breakpoints. */
if (regular_breakpoint_inserted_here_p (aspace, stop_pc))
{
if (!breakpoint_thread_match (aspace, stop_pc, ecs->ptid))
thread_hop_needed = 1;
}
IOW, usually, when one only has a task specific breakpoint at a given
address, things work correctly. Put another task-specific or
non-task-specific breakpoint there, and things break.
A patch that eliminates the special thread hop code in infrun.c is
what exposed this, as after that GDB solely relies on
bpstat_check_breakpoint_conditions to know whether the right or wrong
task hit a breakpoint. IOW, given the latent bug, Ada task-specific
breakpoints become non-task-specific, and that is caught by the
testsuite, as:
break break_me task 3
Breakpoint 2 at 0x4030b0: file /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.ada/tasks/foo.adb, line 27.
(gdb) PASS: gdb.ada/tasks.exp: break break_me task 3
continue
Continuing.
[Switching to Thread 0x7ffff7fcb700 (LWP 17122)]
Breakpoint 2, foo.break_me () at /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.ada/tasks/foo.adb:27
27 null;
(gdb) PASS: gdb.ada/tasks.exp: continue to breakpoint
info tasks
ID TID P-ID Pri State Name
1 63b010 48 Waiting on RV with 2 main_task
* 2 63bd80 1 48 Accepting RV with 1 task_list(1)
3 63f510 1 48 Accept or Select Term task_list(2)
4 642ca0 1 48 Accept or Select Term task_list(3)
(gdb) FAIL: gdb.ada/tasks.exp: info tasks after hitting breakpoint
It was after seeing this that I thought of how to expose the bug with
current mainline.
Tested on x86_64 Fedora 17.
gdb/
2014-02-26 Pedro Alves <palves@redhat.com>
* breakpoint.c (bpstat_check_breakpoint_conditions): Handle
task-specific breakpoints.
gdb/testsuite/
2014-02-26 Pedro Alves <palves@redhat.com>
* gdb.ada/tasks.exp: Set a task-specific breakpoint at break_me
that won't ever trigger. Make sure that GDB reports the correct
breakpoint that caused the stop.
Consider the following code:
type Color is (Black, Red, Green, Blue, White);
type Primary_Table is array (Color range Red .. Blue) of Boolean;
Prim : Primary_Table := (True, False, False);
GDB prints the length of arrays in a fairly odd way:
(gdb) p prim'length
$2 = blue
The length returned should be an integer, not the array index type,
and this patch fixes this.
gdb/ChangeLog:
* ada-lang.c (ada_evaluate_subexp): Set the type of the value
returned by the 'Length attribute to integer.
testsuite/ChangeLog:
* gdb.ada/tick_length_array_enum_idx: New testcase.
type Char_Table is array (Character range Character'First .. Character'Last)
of Natural;
Trying to print the type description of this type currently yields:
(gdb) ptype char_table
type = array ('["00"]' .. '["ff"]') of natural
Although technically correct, it seemed more useful to print the array
range as:
(gdb) ptype char_table
type = array (character) of natural
This patch implements this suggestion.
gdb/ChangeLog:
* ada-typeprint (type_is_full_subrange_of_target_type):
New function.
(print_range): Add parameter bounds_prefered_p. If not set,
try printing range types using the name of their base type.
(print_range_type): Add parameter bounds_prefered_p.
Use it in call to print_range.
(print_array_type, ada_print_type): Update calls to print_range
and print_range_type.
gdb/testsuite/ChangeLog:
* gdb.ada/array_char_idx: New testcase.
Consider the following code:
type Element is abstract tagged null record;
type GADataType is interface;
type Data_Type is new Element and GADataType with record
I : Integer := 42;
end record;
Result1 : Data_Type;
GGG1 : GADataType'Class := GADataType'Class (Result1);
When trying to create a varobj for variable ggg1, GDB currently
returns an object which has no child:
-var-create ggg1 * ggg1
^done,name="ggg1",numchild="0",[...]
This is incorrect, it should return an object which has one child
(field "i"). This is because tagged-type objects are dynamic, and
we need to apply a small transformation in order to get their actual
type. This is already done on the GDB/CLI side in ada-valprint,
and it needs to be done on the ada-varobj side as well.
gdb/ChangeLog:
* ada-varobj.c (ada_varobj_adjust_for_child_access): Convert
tagged type objects to their actual type.
gdb/testsuite/ChangeLog:
* gdb.ada/mi_interface: New testcase.
Consider the following types:
type Time_T is record
Secs : Integer;
end record;
Before : Time_T := (Secs => 1384395743);
In this example, we assume that type Time_T is the number of seconds
since Epoch, and so added a Python pretty-printer, to print this
type in a more human-friendly way. For instance:
(gdb) print before
$1 = Thu Nov 14 02:22:23 2013 (1384395743)
However, we've noticed that things stop working when this type is
embedded inside another record, and we try to print that record.
For instance, with the following declarations:
type Composite is record
Id : Integer;
T : Time_T;
end record;
Afternoon : Composite := (Id => 1, T => (Secs => 1384395865));
(gdb) print afternoon
$2 = (id => 1, t => (secs => 1384395865))
We expected instead:
(gdb) print afternoon
$2 = (id => 1, t => Thu Nov 14 02:24:25 2013 (1384395865))
This patch fixes the problem by making sure that we try to print
each field via a call to val_print, rather than calling ada_val_print
directly. We need to go through val_print, as the val_print
handles all language-independent features such as calling the
pretty-printer, knowing that ada_val_print will get called eventually
if actual Ada-specific printing is required (which should be the
most common scenario).
And because val_print takes the language as parameter, we enhanced
the print_field_values and print_variant_part to also take a language.
As a bonus, this allows us to remove a couple of references to
current_language.
gdb/ChangeLog:
* ada-valprint.c (print_field_values): Add "language" parameter.
Update calls to print_field_values and print_variant_part.
Pass new parameter "language" in call to val_print instead
of "current_language". Replace call to ada_val_print by call
to val_print.
(print_variant_part): Add "language" parameter.
(ada_val_print_struct_union): Update call to print_field_values.
gdb/testsuite/ChangeLog:
* gdb.ada/pp-rec-component.exp, gdb.ada/pp-rec-component.py,
gdb.ada/pp-rec-component/foo.adb, gdb.ada/pp-rec-component/pck.adb,
gdb.ada/pp-rec-component/pck.ads: New files.
This function has the following code:
elt_type = type;
for (i = n; i > 1; i--)
elt_type = TYPE_TARGET_TYPE (type);
For multi-dimension arrays, the code above tries to find the array
type corresponding to the dimension we're trying to inspect.
The problem is that, past the second dimension, the loop does
nothing other than repeat the first iteration. There is a little
thinko where it got the TYPE_TARGET_TYPE of TYPE instead of ELT_TYPE!
To my surprise, I was unable to produce an Ada exemple that demonstrated
the problem. That's because the examples I created all trigger a parallel
___XA type which we then use in place of the ELT_TYPE in order to
determine the bounds - see the code that immediately follows our
loop above:
index_type_desc = ada_find_parallel_type (type, "___XA");
ada_fixup_array_indexes_type (index_type_desc);
if (index_type_desc != NULL)
[...]
So, in order to avoid depending on an Ada example where the compiler
can potentially decide one way or the other, I decided to use an
artificial example, written in C. With ...
int multi[1][2][3];
... forcing the language to Ada, and trying to print the 'last,
we get:
(gdb) p multi'last(1)
$1 = 0
(gdb) p multi'last(2)
$2 = 1
(gdb) p multi'last(3)
$3 = 1 <<<--- This should be 2!
Additionally, I noticed that a couple of check_typedef's were missing.
This patch adds them. And since the variable in question only gets
used within an "else" block, I moved the variable declaration and
use inside that block - making it clear what the scope of the variable
is.
gdb/ChangeLog:
* ada-lang.c (ada_array_bound_from_type): Move the declaration
and assignment of variable "elt_type" inside the else block
where it is used. Add two missing check_typedef calls.
Fix bug where we got TYPE's TYPE_TARGET_TYPE, where in fact
we really wanted to get ELT_TYPE's TYPE_TARGET_TYPE.
gdb/testsuite/ChangeLog:
* gdb.ada/arraydim: New testcase.
This helps with the following issue: Given an Ada program defining
a global variable:
package Pck is
Watch : Integer := 1974;
end Pck;
When printing the address of this variable, GDB also tries to print
the associated symbol name:
(gdb) p watch'address
$1 = (access integer) 0x6139d8 <pck__watch>
^^
||
The problem is that GDB prints the variable's linkage name, instead
of its natural name. This is because the language of the associated
minimal symbol never really gets set.
This patch adds handling for Ada symbols in symbol_find_demangled_name.
After this patch, we now get:
(gdb) p watch'address
$1 = (access integer) 0x6139d8 <pck.watch>
^
|
gdb/ChangeLog:
* symtab.c (symbol_find_demangled_name): Add handling of
Ada symbols.
gdb/testsuite/ChangeLog:
* gdb.ada/int_deref.exp: Add test verifying that we print
the decoded symbol name when printing the address of Ada
symbols.
These files are source files and have no business being +x. We couldn't
easily fix it in CVS (you need login+write access to the raw rcs files),
but we can fix this w/git.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Consider the following code:
type Ptr is access all Integer;
IP : Ptr := new Integer'(123);
IP is the Ada exception of a pointer to an integer. To dereference
the pointer and get its value, the user uses the reserved word "all"
as follow:
(gdb) p ip.all
$1 = 123
Ada being a case-insensitive language, the casing should not matter.
Unfortunately, for the reserved word "all", things don't work. For
instance:
(gdb) p ip.ALL
Type integer is not a structure or union type
This patch fixes the problem.
gdb/ChangeLog:
* ada-lex.l (find_dot_all): Use strncasecmp instead of strncmp.
gdb/testsuite/ChangeLog:
* gdb.ada/dot_all: New testcase.
Consider the following variable:
type Small is range -128 .. 127;
SR : Small := 48;
Trying to get its value as an integer within Python code yields:
(gdb) python sr = gdb.parse_and_eval('sr')
(gdb) python print int(sr)
Traceback (most recent call last):
File "<string>", line 1, in <module>
gdb.error: Cannot convert value to int.
Error while executing Python code.
This is happening because our variable is a range type, and
py-value's is_intlike does not handle TYPE_CODE_RANGE. This
patch fixes this.
gdb/ChangeLog:
* python/py-value.c (is_intlike): Add TYPE_CODE_RANGE handling.
gdb/testsuite/ChangeLog:
* gdb.ada/py_range: New testcase.
In the case where the GNAT runtime was built with full debugging info,
several of the exceptions defined there might have a name contain
the word "global". To make this less likely, this patch renames
the exception name, replacing "Global" by "Global_GDB". It still
keeps the exeption name relatively short, while it is unlikely that
the GNAT runtime has an exception whose name explicitly mentions GDB,
and even less likely that it contains "Global_GDB".
gdb/testsuite/ChangeLog:
* info_exc/const.ads (Aint_Global_GDB_E): Renames Aint_Global_E.
* info_exc/foo.adb: Adjust to new exception name.
* info_exc.exp: Adjust after exception renaming in const.ads.
Update "info exception global" test to test "info exceptions
global_gdb" instead.
* mi_exc_info/const.ads (Aint_Global_GDB_E): Renames Aint_Global_E.
* mi_exc_info/foo.adb (Adjust to new exception name.
* mi_exc_info.exp: Adjust after exception renaming in const.ads.
Update "-info-ada-exceptions global" test to test
"-info-ada-exceptions global_gdb" instead.
If the runtime has full debug info, then the non-standard exceptions
declared in the GNAT runtime will appear in the list of exceptions
printed by GDB ("info exceptions" or "-info-ada-exceptions").
This is valid output, so this patch allows for it.
gdb/testsuite/ChangeLog:
* gdb.ada/info_exc.exp: Allow other global exceptions to be
listed in the output of "info exceptions".
* gdb.ada/mi_exc_info.exp: Allow other global exceptions to be
listed in the output of "-info-ada-exceptions".
This patch fixes some spurious failures when the inferior is linked
against the shared version of libgnat by default, as appears to be
the case on many GNU/Linux distributions. When that happens, we have
to start the program in order to ensure that the GNAT runtime is
mapped to memory, in order for us to find the standard exceptions
(defined within the runtime). Otherwise, they will not be shown,
as expected, by the debugger.
gdb/testsuite/ChangeLog:
* gdb.ada/info_exc.exp: Start inferior before starting
the "info exceptions" tests.
* gdb.ada/mi_exc_info.exp: Start inferior before starting
the "-info-ada-exceptions" tests.
Consider the following code, compiled at -O2 on ppc-linux:
procedure Increment (Val : in out Float; Msg : String);
The implementation does not really matter in this case). In our example,
this function is being called from a function with Param_1 set to 99.0.
Trying to break inside that function, and running until reaching that
breakpoint yields:
(gdb) b increment
Breakpoint 1 at 0x100014b4: file callee.adb, line 6.
(gdb) run
Starting program: /[...]/foo
Breakpoint 1, callee.increment (val=99.0, val@entry=0.0, msg=...)
at callee.adb:6
6 if Val > 200.0 then
The @entry value for parameter "val" is incorrect, it should be 99.0.
The associated call-site parameter DIE looks like this:
.uleb128 0xc # (DIE (0x115) DW_TAG_GNU_call_site_parameter)
.byte 0x2 # DW_AT_location
.byte 0x90 # DW_OP_regx
.uleb128 0x21
.byte 0x3 # DW_AT_GNU_call_site_value
.byte 0xf5 # DW_OP_GNU_regval_type
.uleb128 0x3f
.uleb128 0x25
The DW_AT_GNU_call_site_value uses a DW_OP_GNU_regval_type
operation, referencing register 0x3f=63, which is $f31,
an 8-byte floating register. In that register, the value is
stored using the usual 8-byte float format:
(gdb) info float
f31 99.0 (raw 0x4058c00000000000)
The current code evaluating DW_OP_GNU_regval_type operations
currently is (dwarf2expr.c:execute_stack_op):
result = (ctx->funcs->read_reg) (ctx->baton, reg);
result_val = value_from_ulongest (address_type, result);
result_val = value_from_contents (type,
value_contents_all (result_val));
What the ctx->funcs->read_reg function does is read the contents
of the register as if it contained an address. The rest of the code
continues that assumption, thinking it's OK to then use that to
create an address/ulongest struct value, which we then re-type
to the type specified by DW_OP_GNU_regval_type.
We're getting 0.0 above because the read_reg implementations
end up treating the contents of the FP register as an integral,
reading only 4 out of the 8 bytes. Being a big-endian target,
we read the high-order ones, which gives us zero.
This patch fixes the problem by introducing a new callback to
read the contents of a register as a given type, and then adjust
the handling of DW_OP_GNU_regval_type to use that new callback.
gdb/ChangeLog:
* dwarf2expr.h (struct dwarf_expr_context_funcs) <read_reg>:
Extend the documentation a bit.
<get_reg_value>: New field.
* dwarf2loc.c (dwarf_expr_get_reg_value)
(needs_frame_get_reg_value): New functions.
(dwarf_expr_ctx_funcs, needs_frame_ctx_funcs): Add "get_reg_value"
callback.
* dwarf2-frame.c (get_reg_value): New function.
(dwarf2_frame_ctx_funcs): Add "get_reg_value" callback.
* dwarf2expr.c (execute_stack_op) <DW_OP_GNU_regval_type>:
Use new callback to compute result_val.
gdb/testsuite/ChangeLog:
* gdb.ada/O2_float_param: New testcase.
This patch implements a new GDB/MI command implementing the equivalent
of the "info exceptions" CLI command. The command syntax is:
-info-ada-exceptions [REGEXP]
Here is an example of usage (slightly formatted by hand to make it
easier to read):
-info-ada-exceptions ions\.a_
^done,ada-exceptions=
{nr_rows="2",nr_cols="2",
hdr=[{width="1",alignment="-1",col_name="name",colhdr="Name"},
{width="1",alignment="-1",col_name="address",colhdr="Address"}],
body=[{name="global_exceptions.a_global_exception",
address="0x0000000000613a80"},
{name="global_exceptions.a_private_exception",
address="0x0000000000613ac0"}]}
Also, in order to allow graphical frontends to easily determine
whether this command is available or not, the output of the
"-list-features" command has been augmented to contain
"info-ada-exceptions".
gdb/Changelog:
* mi/mi-cmds.h (mi_cmd_info_ada_exceptions): Add declaration.
* mi/mi-cmds.c (mi_cmds): Add entry for -info-ada-exceptions
command.
* mi/mi-cmd-info.c: #include "ada-lang.c" and "arch-utils.c".
(mi_cmd_info_ada_exceptions): New function.
* mi/mi-main.c (mi_cmd_list_features): Add "info-ada-exceptions".
gdb/testsuite/ChangeLog:
* gdb.ada/mi_exc_info: New testcase.
This patch adds a new command "info exceptions" whose purpose is to
provide the list of exceptions currently defined in the inferior.
The usage is:
(gdb) info exceptions [REGEXP]
Without argument, the command lists all exceptions. Otherwise,
only those whose name match REGEXP are listed.
For instance:
(gdb) info exceptions
All defined Ada exceptions:
constraint_error: 0x613dc0
program_error: 0x613d40
storage_error: 0x613d00
tasking_error: 0x613cc0
global_exceptions.a_global_exception: 0x613a80
global_exceptions.a_private_exception: 0x613ac0
The name of the command, as well as its output is part of a legacy
I inherited long ago. It's output being parsed by frontends such as
GPS, I cannot easily change it. Same for the command name.
The implementation is mostly self-contained, and is written in a way
that should make it easy to implement the GDB/MI equivalent. The
careful reviewer will notice that the code added in ada-lang.h could
normally be made private inside ada-lang.c. But these will be used
by the GDB/MI implementation. Rather than making those private now,
only to move them later, I've made them public right away.
gdb/ChangeLog:
* ada-lang.h: #include "vec.h".
(struct ada_exc_info): New.
(ada_exc_info): New typedef.
(DEF_VEC_O(ada_exc_info)): New vector.
(ada_exceptions_list): Add declaration.
* ada-lang.c (ada_is_exception_sym)
(ada_is_non_standard_exception_sym, compare_ada_exception_info)
(sort_remove_dups_ada_exceptions_list)
(ada_exc_search_name_matches, ada_add_standard_exceptions)
(ada_add_exceptions_from_frame, ada_add_global_exceptions)
(ada_exceptions_list_1, ada_exceptions_list)
(info_exceptions_command): New function.
(_initialize_ada_language): Add "info exception" command.
gdb/testsuite/ChangeLog:
* gdb.ada/info_exc: New testcase.
When using the GDB/MI commands to insert a catchpoint on a specific
Ada exception, any re-evaluation of that catchpoint (for instance
a re-evaluation performed after a shared library got mapped by the
inferior) fails. For instance, with any Ada program:
(gdb)
-catch-exception -e program_error
^done,bkptno="1",bkpt={[...]}
(gdb)
-exec-run
=thread-group-started,id="i1",pid="28315"
=thread-created,id="1",group-id="i1"
^running
*running,thread-id="all"
(gdb)
=library-loaded,[...]
&"warning: failed to reevaluate internal exception condition for catchpoint 1: No definition of \"exec\" in current context.\n"
&"warning: failed to reevaluate internal exception condition for catchpoint 1: No definition of \"exec\" in current context.\n"
[...]
The same is true if using an Ada exception catchpoint.
The problem comes from the fact that that we deallocate the strings
given as arguments to create_ada_exception_catchpoint, while the latter
just makes shallow copies of those strings, thus creating dandling
pointers.
This patch fixes the issue by passing freshly allocated strings to
create_ada_exception_catchpoint, while at the same time updating
create_ada_exception_catchpoint's documentation to make it clear
that deallocating the strings is no longer the responsibility of
the caller.
gdb/ChangeLog:
* ada-lang.c (create_ada_exception_catchpoint): Enhance
the documentation of fields "except_string" and "condition".
* mi/mi-cmd-catch.c (mi_cmd_catch_assert): Reallocate
CONDITION on the heap before passing it to
create_ada_exception_catchpoint.
(mi_cmd_catch_exception): Likewise for EXCEPTION_NAME and
CONDITION.
gdb/testsuite/ChangeLog:
* gdb.ada/mi_ex_cond: New testcase.
Tested on x86_64-linux. The "-break-list" test FAILs without
this patch.
... in place of the CLI "catch ..." commands. The latter were used
because the GDB/MI equivalents were not available at the time.
gdb/testsuite/ChangeLog:
* gdb.ada/mi_catch_ex.exp: Adjusts all "catch ..." tests to
use the appropriate GDB/MI command instead, and verify
the test output.
This patch adds some tests that evidence a regression fixed by
the following patch from Pedro Alves:
[PATCH] ada-lang.c:coerce_unspec_val_to_type: Preserve laziness
http://www.sourceware.org/ml/gdb-patches/2013-07/msg00178.html
gdb/testsuite/ChangeLog:
* gdb.ada/arrayptr/foo.adb: Add some code defining an access
to a packed array.
* gdb.ada/arrayptr.exp: Add a few tests using that new access
to packed array.
If enough information is provided by the compiler, the debugger
now prints the entry value of various parameters:
(gdb) continue
Continuing.
Breakpoint 2, pck.call_me (w=w@entry=50) at [...]
20 Last_Word := W;
This patch adjusts the expected output to allow an optional
"w@entry=" in the parameter value.
gdb/testsuite/ChangeLog:
* gdb.ada/small_reg_param.exp: Accept optional entry value
for parameter "w".
This makes sure that the types of the arguments are taken into account
when performing an inferior function call to a non-C (or C-like)
function. In particular, this makes sure that the arguments are
appropriatly converted to the correct type.
For instance, on x86_64-linux, with the following Ada code:
procedure Set_Float (F : Float) is
begin
Global_Float := F;
end Set_Float;
The following sequence shows that Float arguments are incorrectly
passed (Ada's Float type is the equivalent of type "float" in C):
(gdb) call set_float (2.0)
(gdb) print global_float
$1 = 0.0
Putting a breakpoint inside set_float to inspect the value of
register xmm0 gives the first hint of the problem:
(gdb) p $xmm0
$2 = (v4_float => (0 => 0.0, 2.0, 0.0, 0.0),
v2_double => (0 => 2.0, 0.0),
[...]
It shows that the argument was passed as a double.
The code responsible for doing appropriate type conversions
for the arguments (value_arg_coerce) found that our function
was not prototyped, and thus could not use typing information
for the arguments. Instead, it defaulted to the value of "set
coerce-float-to-double", which by default is true, to determine
the argument type.
This patch fixes the problem by setting the PROTOTYPE flag
for all functions of any language except C and Objective C.
gdb/ChangeLog:
* dwarf2read.c (prototyped_function_p): New function.
(read_subroutine_type): Use it.
gdb/testsuite/ChangeLog:
* gdb.ada/float_param: New testcase.
This results in an internal-warning when trying the completion
when in Ada mode:
(gdb) b simple<TAB>
/[...]/cleanups.c:265: internal-warning: restore_my_cleanups has found a stale cleanup
A problem internal to GDB has been detected,
further debugging may prove unreliable.
Quit this debugging session? (y or n)
gdb/ChangeLog:
* ada-lang.c (ada_make_symbol_completion_list): Make sure
all cleanups are done before returning from this function.
gdb/testsuite/ChangeLog:
* gdb.ada/complete.exp: Add test verifying completion using
the "tab" key.
The debugger sometimes prints strange function names for given
addresses. For instance, with the following source code...
4 procedure Foo is
5 A : Integer;
6 begin
7 Do_Nothing (A'Address);
8 end Foo;
... we can see...
(gdb) info line 5
Line 5 of "foo.adb" starts at address 0x4017ca <_ada_foo+6>
and ends at 0x4017d2 <_fu29__system__scalar_values__is_is4+7>.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
_fu29__system__scalar_values__is_is4 is an artificial symbol
generated by the linker, and interferes with the pc-to-symbol
resolution. There isn't much in the general minimal_symbol
data that could help us identify them, so this patch changes
the COFF reader to simply ignore them.
gdb/ChangeLog:
* coffread.c (is_import_fixup_symbol): New function.
(record_minimal_symbol): Use is_import_fixup_symbol to
detect import fixup symbols, and discard them.
gdb/testsuite/ChangeLog:
* gdb.ada/win_fu_syms: New testcase.
GDB treats the identifiers 'if', 'thread', and 'task' unconditionally
as expression delimiters in Ada mode, which is correct for 'if' and 'task',
but wrong for 'thread' in cases such as
print thread
Borrowing from c-exp.y, we observe that 'thread' must be followed by
numerals, whereas identifiers never are and treat them as delimiters
only in that case.
In the process, the current also refactors and incidentally fixes the
code for rewinding the input to before the delimiting tokens. For
example, the code
watch expr if i > 2
fails because the input is only rewound to just before the 'i',
leaving the 'if' as part of the expression (and thus making the
rest look like trailing junk rather than a conditional clause).
gdb/ChangeLog:
* ada-lex.l (rules): Only recognize 'thread' as a
delimiter when followed by numerals, as for c-exp.y.
Use new rewind_to_char function to rewind the input for
expression-delimiting tokens.
(rewind_to_char): New function.
gdb/testsuite/ChangeLog:
* gdb.ada/expr_delims.exp: New file.
* gdb.ada/expr_delims/foo.adb: New file.
* gdb.ada/expr_delims/pck.ads: New file.
* gdb.ada/expr_delims/pck.adb: New file.
Two modifications:
1. The addition of 2013 to the copyright year range for every file;
2. The use of a single year range, instead of potentially multiple
year ranges, as approved by the FSF.
For displaying the full view of a class-wide object, GDB relies on
the assumption that this view will have the same address as the
address of the object. In the case of simple inheritance, this
assumption is correct; the proper type is deduced by decoding
the tag of the object and converting the result to this full-view
type.
Consider for example an abstract class Shape, a child Circle
which implements an interface Drawable, and the corresponding
following objects:
My_Circle : Circle := ((1, 2), 3);
My_Shape : Shape'Class := Shape'Class (My_Circle);
My_Drawable : Drawable'Class := Drawable'Class (My_Circle);
To display My_Shape, the debugger first extracts the tag (an internal
field, usually the first one of the record):
(gdb) p my_shape'address
$2 = (system.address) 0x8063e28
(gdb) x/x my_shape'address
0x8063e28 <classes__my_shape>: 0x08059ec4
Then the type specific data and the expanded name of the tag is read
from there:
(gdb) p my_shape'tag
$3 = (access ada.tags.dispatch_table) 0x8059ec4 (classes.circle)
To get the full view, the debugger converts to the corresponding type:
(gdb) p {classes.circle}0x8063e28
$4 = (center => (x => 1, y => 2), radius => 3)
Now, in the case of multiple inheritance, the assumption does not hold
anymore. The address that we have usually points to some
place lower. The offset to the original address is saved in the field
Offset_To_Top of the metadata that are above the tag, at address
obj'tag - 8. In the case of my_shape, this offset is 0:
(gdb) x/x my_shape'tag - 8
0x8059ebc <classes__circleT+12>: 0x00000000
...but in the case of an interface-wide object, it is not null:
(gdb) x/x my_drawable'tag - 8
0x8063b28 <classes__classes__circle_classes__drawable1T56s+12>: 0x00000004
(gdb) p {classes.circle}(my_drawable'address - 4)
$7 = (center => (x => 1, y => 2), radius => 3)
The following change handles this relocation in the most common cases.
Remaining cases that are still to be investigated are signaled by
comments.
gdb/ChangeLog:
* ada-lang.h (ada_tag_value_at_base_address): New function
declaration.
* ada-lang.c (is_ada95_tag, ada_tag_value_at_base_address):
New functions.
(ada_to_fixed_type_1, ada_evaluate_subexp): Let ada_tag_base_address
relocate the class-wide value if need be.
(ada_value_struct_elt, ada_value_ind, ada_coerce_ref):
Let ada_tag_value_at_base_address relocate the class-wide access/ref
before dereferencing it.
* ada-valprint.c (ada_val_print_1): Relocate to base address
before displaying the content of an interface-wide ref.
gdb/testsuite/ChangeLog:
* gdb.ada/ptype_tagged_param.exp: Adjust expected output in
ptype test.
Given the following variable declaration...
Www : Wide_String := "12345";
... this patch allows the following assignment to work:
(gdb) set variable www := "qwert"
Without this patch, the debugger rejects the assignment because
the size of the array elements are different:
(gdb) set www := "asdfg"
Incompatible types in assignment
(on the lhs, we have an array of 2-bytes elements, and on the rhs,
we have a standard 1-byte string).
gdb/ChangeLog:
* ada-lang.c (ada_same_array_size_p): New function.
(ada_promote_array_of_integrals): New function.
(coerce_for_assign): Add handling of arrays where the elements
are integrals of a smaller size than the size of the target
array element type.
gdb/testsuite/ChangeLog:
* gdb.ada/set_wstr: New testcase.
