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[commit/Ada] dynamic sized packed array in variant record
- From: Joel Brobecker <brobecker at adacore dot com>
- To: gdb-patches at sourceware dot org
- Date: Wed, 20 May 2009 11:45:37 -0700
- Subject: [commit/Ada] dynamic sized packed array in variant record
Hello,
One of our customers recently reported an issue when trying to print
a variant record containing a packed array whose bounds are dynamic.
I've been able to write a small reproducer, which will be used for
our testcase. The code looks like this:
type Octal is new Integer range 0 .. 7;
type Octal_Array is array (Positive range <>) of Octal;
pragma Pack (Octal_Array);
type Octal_Buffer (Size : Positive) is record
Buffer : Octal_Array (1 .. Size);
Length : Integer;
end record;
There were actually several issues preventing us from printing
an object of type Octal_Buffer correctly. But the meat of the problem
was the fact that we were not computing the bounds of our packed array
correctly. The array bounds are dependent on the discriminant, and
that fact is encoded in the ___XA parallel to our packed array type;
but the routines fixing packed array types do not take this type into
account.
Interestingly, someone asked about a strange comment in ada-lang.c:
to_fixed_array_type:
if (ada_is_packed_array_type (type0) /* revisit? */
|| TYPE_FIXED_INSTANCE (type0))
Rather than duplicate the code handling ___XA types et al, I decided
to make this routine handle packed array types as well. I therefore
was able to get rid of the check for packed array types, and its
associated comment.
In terms of the patch itself, as I said, I needed to fix several issues:
1. The first issue is when we tried to fix field Buffer inside
record Octal_Buffer. It is encoded as a PAD (aka aligner) type
for which there is an XVS type. We code that fixes the dynamic
part of a variant record type neeeds to compute its associated
fixed type, and for that, tried to get its "base type"
(see ada_get_base_type), which lead us to follow the XVS type
mentioned above. But the encoding says that we should always
unwrap the type rather than follow the XVS. So I fixed that first.
2. The second issue was that the PAD type did not have a valid size,
since the size of that component is not statically known (it depends
on the value if the discriminant). As a result, we need to unwrap
that PAD type and fix the underlying type. That's the second change
in ada_template_to_fixed_record_type_1.
3. And finally, the last issue was the issue described at the beginning
of this email: Compute the bounds of our packed array properly.
This revealed a couple of holes:
3.a: Subscripting a packed array: The evaluation of the array
entity in our expression returned a value that has already
been fixed, whereas the code wasn't realizing that. So it
handled the packed array as a normal array, and we ended up
computing the wrong value for our array element. This is
the new guard added in ada_evaluate_subexp/OP_FUNCALL.
3.b: Subscripting a pointer to a packed array: This is the last
change in decode_packed_array. This routine noticed that
our array was in fact a pointer to a packed array, and thus
proceeded to dereference it. However, using ada_value_ind
had the side-effect of also fixing the array, which we did
not expect. So when decode_packed_array then tries to fix
the resulting value, it finds that it's not a packed array,
and thus errors out. The fix was to avoid the side-effect
by calling value_ind instead of ada_value_ind.
2009-05-20 Joel Brobecker <brobecker@adacore.com>
* ada-lang.c (decode_packed_array): If the value is a pointer to
an array, then use value_ind to dereference it, not ada_value_ind.
(ada_template_to_fixed_record_type_1): Handle the case where a
dynamic field is an aligner type.
(to_fixed_array_type): Add handling for packed array types.
(ada_get_base_type): Do not follow the XVS type if the type is
an aligner type.
(ada_evaluate_subexp): Split a few statements up for clarity
and debuggability.
<OP_FUNCALL>: Add handling of the case of a packed array that
has already been fixed.
2009-05-20 Joel Brobecker <brobecker@adacore.com>
* gdb.ada/variant_record_packed_array: New testcase.
Tested on x86-linux, with stabs & dwarf. Also tested on x86_64-linux,
with dwarf. No regression. Fixes the new testcase.
Will commit in a few days if our nightly builds reveal nothing scary.
--
Joel
diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c
index 3b33824..c0cf781 100644
--- a/gdb/ada-lang.c
+++ b/gdb/ada-lang.c
@@ -1822,8 +1822,15 @@ decode_packed_array (struct value *arr)
struct type *type;
arr = ada_coerce_ref (arr);
+
+ /* If our value is a pointer, then dererence it. Make sure that
+ this operation does not cause the target type to be fixed, as
+ this would indirectly cause this array to be decoded. The rest
+ of the routine assumes that the array hasn't been decoded yet,
+ so we use the basic "value_ind" routine to perform the dereferencing,
+ as opposed to using "ada_value_ind". */
if (TYPE_CODE (value_type (arr)) == TYPE_CODE_PTR)
- arr = ada_value_ind (arr);
+ arr = value_ind (arr);
type = decode_packed_array_type (value_type (arr));
if (type == NULL)
@@ -6842,6 +6849,11 @@ ada_template_to_fixed_record_type_1 (struct type *type,
}
else if (is_dynamic_field (type, f))
{
+ const gdb_byte *field_valaddr = valaddr;
+ CORE_ADDR field_address = address;
+ struct type *field_type =
+ TYPE_TARGET_TYPE (TYPE_FIELD_TYPE (type, f));
+
if (dval0 == NULL)
{
/* rtype's length is computed based on the run-time
@@ -6855,18 +6867,36 @@ ada_template_to_fixed_record_type_1 (struct type *type,
else
dval = dval0;
- /* Get the fixed type of the field. Note that, in this case, we
- do not want to get the real type out of the tag: if the current
- field is the parent part of a tagged record, we will get the
- tag of the object. Clearly wrong: the real type of the parent
- is not the real type of the child. We would end up in an infinite
- loop. */
- TYPE_FIELD_TYPE (rtype, f) =
- ada_to_fixed_type
- (ada_get_base_type
- (TYPE_TARGET_TYPE (TYPE_FIELD_TYPE (type, f))),
- cond_offset_host (valaddr, off / TARGET_CHAR_BIT),
- cond_offset_target (address, off / TARGET_CHAR_BIT), dval, 0);
+ /* If the type referenced by this field is an aligner type, we need
+ to unwrap that aligner type, because its size might not be set.
+ Keeping the aligner type would cause us to compute the wrong
+ size for this field, impacting the offset of the all the fields
+ that follow this one. */
+ if (ada_is_aligner_type (field_type))
+ {
+ long field_offset = TYPE_FIELD_BITPOS (field_type, f);
+
+ field_valaddr = cond_offset_host (field_valaddr, field_offset);
+ field_address = cond_offset_target (field_address, field_offset);
+ field_type = ada_aligned_type (field_type);
+ }
+
+ field_valaddr = cond_offset_host (field_valaddr,
+ off / TARGET_CHAR_BIT);
+ field_address = cond_offset_target (field_address,
+ off / TARGET_CHAR_BIT);
+
+ /* Get the fixed type of the field. Note that, in this case,
+ we do not want to get the real type out of the tag: if
+ the current field is the parent part of a tagged record,
+ we will get the tag of the object. Clearly wrong: the real
+ type of the parent is not the real type of the child. We
+ would end up in an infinite loop. */
+ field_type = ada_get_base_type (field_type);
+ field_type = ada_to_fixed_type (field_type, field_valaddr,
+ field_address, dval, 0);
+
+ TYPE_FIELD_TYPE (rtype, f) = field_type;
TYPE_FIELD_NAME (rtype, f) = TYPE_FIELD_NAME (type, f);
bit_incr = fld_bit_len =
TYPE_LENGTH (TYPE_FIELD_TYPE (rtype, f)) * TARGET_CHAR_BIT;
@@ -7192,11 +7222,15 @@ to_fixed_array_type (struct type *type0, struct value *dval,
{
struct type *index_type_desc;
struct type *result;
+ int packed_array_p;
- if (ada_is_packed_array_type (type0) /* revisit? */
- || TYPE_FIXED_INSTANCE (type0))
+ if (TYPE_FIXED_INSTANCE (type0))
return type0;
+ packed_array_p = ada_is_packed_array_type (type0);
+ if (packed_array_p)
+ type0 = decode_packed_array_type (type0);
+
index_type_desc = ada_find_parallel_type (type0, "___XA");
if (index_type_desc == NULL)
{
@@ -7214,7 +7248,10 @@ to_fixed_array_type (struct type *type0, struct value *dval,
consult the object tag. */
struct type *elt_type = ada_to_fixed_type (elt_type0, 0, 0, dval, 1);
- if (elt_type0 == elt_type)
+ /* Make sure we always create a new array type when dealing with
+ packed array types, since we're going to fix-up the array
+ type length and element bitsize a little further down. */
+ if (elt_type0 == elt_type && !packed_array_p)
result = type0;
else
result = create_array_type (alloc_type (TYPE_OBJFILE (type0)),
@@ -7254,6 +7291,21 @@ to_fixed_array_type (struct type *type0, struct value *dval,
error (_("array type with dynamic size is larger than varsize-limit"));
}
+ if (packed_array_p)
+ {
+ /* So far, the resulting type has been created as if the original
+ type was a regular (non-packed) array type. As a result, the
+ bitsize of the array elements needs to be set again, and the array
+ length needs to be recomputed based on that bitsize. */
+ int len = TYPE_LENGTH (result) / TYPE_LENGTH (TYPE_TARGET_TYPE (result));
+ int elt_bitsize = TYPE_FIELD_BITSIZE (type0, 0);
+
+ TYPE_FIELD_BITSIZE (result, 0) = TYPE_FIELD_BITSIZE (type0, 0);
+ TYPE_LENGTH (result) = len * elt_bitsize / HOST_CHAR_BIT;
+ if (TYPE_LENGTH (result) * HOST_CHAR_BIT < len * elt_bitsize)
+ TYPE_LENGTH (result)++;
+ }
+
TYPE_FIXED_INSTANCE (result) = 1;
return result;
}
@@ -7677,6 +7729,21 @@ ada_get_base_type (struct type *raw_type)
if (raw_type == NULL || TYPE_CODE (raw_type) != TYPE_CODE_STRUCT)
return raw_type;
+ if (ada_is_aligner_type (raw_type))
+ /* The encoding specifies that we should always use the aligner type.
+ So, even if this aligner type has an associated XVS type, we should
+ simply ignore it.
+
+ According to the compiler gurus, an XVS type parallel to an aligner
+ type may exist because of a stabs limitation. In stabs, aligner
+ types are empty because the field has a variable-sized type, and
+ thus cannot actually be used as an aligner type. As a result,
+ we need the associated parallel XVS type to decode the type.
+ Since the policy in the compiler is to not change the internal
+ representation based on the debugging info format, we sometimes
+ end up having a redundant XVS type parallel to the aligner type. */
+ return raw_type;
+
real_type_namer = ada_find_parallel_type (raw_type, "___XVS");
if (real_type_namer == NULL
|| TYPE_CODE (real_type_namer) != TYPE_CODE_STRUCT
@@ -8315,6 +8382,225 @@ ada_value_cast (struct type *type, struct value *arg2, enum noside noside)
return value_cast (type, arg2);
}
+/* Evaluating Ada expressions, and printing their result.
+ ------------------------------------------------------
+
+ We usually evaluate an Ada expression in order to print its value.
+ We also evaluate an expression in order to print its type, which
+ happens during the EVAL_AVOID_SIDE_EFFECTS phase of the evaluation,
+ but we'll focus mostly on the EVAL_NORMAL phase. In practice, the
+ EVAL_AVOID_SIDE_EFFECTS phase allows us to simplify certain aspects of
+ the evaluation compared to the EVAL_NORMAL, but is otherwise very
+ similar.
+
+ Evaluating expressions is a little more complicated for Ada entities
+ than it is for entities in languages such as C. The main reason for
+ this is that Ada provides types whose definition might be dynamic.
+ One example of such types is variant records. Or another example
+ would be an array whose bounds can only be known at run time.
+
+ The following description is a general guide as to what should be
+ done (and what should NOT be done) in order to evaluate an expression
+ involving such types, and when. This does not cover how the semantic
+ information is encoded by GNAT as this is covered separatly. For the
+ document used as the reference for the GNAT encoding, see exp_dbug.ads
+ in the GNAT sources.
+
+ Ideally, we should embed each part of this description next to its
+ associated code. Unfortunately, the amount of code is so vast right
+ now that it's hard to see whether the code handling a particular
+ situation might be duplicated or not. One day, when the code is
+ cleaned up, this guide might become redundant with the comments
+ inserted in the code, and we might want to remove it.
+
+ When evaluating Ada expressions, the tricky issue is that they may
+ reference entities whose type contents and size are not statically
+ known. Consider for instance a variant record:
+
+ type Rec (Empty : Boolean := True) is record
+ case Empty is
+ when True => null;
+ when False => Value : Integer;
+ end case;
+ end record;
+ Yes : Rec := (Empty => False, Value => 1);
+ No : Rec := (empty => True);
+
+ The size and contents of that record depends on the value of the
+ descriminant (Rec.Empty). At this point, neither the debugging
+ information nor the associated type structure in GDB are able to
+ express such dynamic types. So what the debugger does is to create
+ "fixed" versions of the type that applies to the specific object.
+ We also informally refer to this opperation as "fixing" an object,
+ which means creating its associated fixed type.
+
+ Example: when printing the value of variable "Yes" above, its fixed
+ type would look like this:
+
+ type Rec is record
+ Empty : Boolean;
+ Value : Integer;
+ end record;
+
+ On the other hand, if we printed the value of "No", its fixed type
+ would become:
+
+ type Rec is record
+ Empty : Boolean;
+ end record;
+
+ Things become a little more complicated when trying to fix an entity
+ with a dynamic type that directly contains another dynamic type,
+ such as an array of variant records, for instance. There are
+ two possible cases: Arrays, and records.
+
+ Arrays are a little simpler to handle, because the same amount of
+ memory is allocated for each element of the array, even if the amount
+ of space used by each element changes from element to element.
+ Consider for instance the following array of type Rec:
+
+ type Rec_Array is array (1 .. 2) of Rec;
+
+ The type structure in GDB describes an array in terms of its
+ bounds, and the type of its elements. By design, all elements
+ in the array have the same type. So we cannot use a fixed type
+ for the array elements in this case, since the fixed type depends
+ on the actual value of each element.
+
+ Fortunately, what happens in practice is that each element of
+ the array has the same size, which is the maximum size that
+ might be needed in order to hold an object of the element type.
+ And the compiler shows it in the debugging information by wrapping
+ the array element inside a private PAD type. This type should not
+ be shown to the user, and must be "unwrap"'ed before printing. Note
+ that we also use the adjective "aligner" in our code to designate
+ these wrapper types.
+
+ These wrapper types should have a constant size, which is the size
+ of each element of the array. In the case when the size is statically
+ known, the PAD type will already have the right size, and the array
+ element type should remain unfixed. But there are cases when
+ this size is not statically known. For instance, assuming that
+ "Five" is an integer variable:
+
+ type Dynamic is array (1 .. Five) of Integer;
+ type Wrapper (Has_Length : Boolean := False) is record
+ Data : Dynamic;
+ case Has_Length is
+ when True => Length : Integer;
+ when False => null;
+ end case;
+ end record;
+ type Wrapper_Array is array (1 .. 2) of Wrapper;
+
+ Hello : Wrapper_Array := (others => (Has_Length => True,
+ Data => (others => 17),
+ Length => 1));
+
+
+ The debugging info would describe variable Hello as being an
+ array of a PAD type. The size of that PAD type is not statically
+ known, but can be determined using a parallel XVZ variable.
+ In that case, a copy of the PAD type with the correct size should
+ be used for the fixed array.
+
+ However, things are slightly different in the case of dynamic
+ record types. In this case, in order to compute the associated
+ fixed type, we need to determine the size and offset of each of
+ its components. This, in turn, requires us to compute the fixed
+ type of each of these components.
+
+ Consider for instance the example:
+
+ type Bounded_String (Max_Size : Natural) is record
+ Str : String (1 .. Max_Size);
+ Length : Natural;
+ end record;
+ My_String : Bounded_String (Max_Size => 10);
+
+ In that case, the position of field "Length" depends on the size
+ of field Str, which itself depends on the value of the Max_Size
+ discriminant. In order to fix the type of variable My_String,
+ we need to fix the type of field Str. Therefore, fixing a variant
+ record requires us to fix each of its components.
+
+ However, if a component does not have a dynamic size, the component
+ should not be fixed. In particular, fields that use a PAD type
+ should not fixed. Here is an example where this might happen
+ (assuming type Rec above):
+
+ type Container (Big : Boolean) is record
+ First : Rec;
+ After : Integer;
+ case Big is
+ when True => Another : Integer;
+ when False => null;
+ end case;
+ end record;
+ My_Container : Container := (Big => False,
+ First => (Empty => True),
+ After => 42);
+
+ In that example, the compiler creates a PAD type for component First,
+ whose size is constant, and then positions the component After just
+ right after it. The offset of component After is therefore constant
+ in this case.
+
+ The debugger computes the position of each field based on an algorithm
+ that uses, among other things, the actual position and size of the field
+ preceding it. Let's now imagine that the user is trying to print the
+ value of My_Container. If the type fixing was recursive, we would
+ end up computing the offset of field After based on the size of the
+ fixed version of field First. And since in our example First has
+ only one actual field, the size of the fixed type is actually smaller
+ than the amount of space allocated to that field, and thus we would
+ compute the wrong offset of field After.
+
+ Unfortunately, we need to watch out for dynamic components of variant
+ records (identified by the ___XVL suffix in the component name).
+ Even if the target type is a PAD type, the size of that type might
+ not be statically known. So the PAD type needs to be unwrapped and
+ the resulting type needs to be fixed. Otherwise, we might end up
+ with the wrong size for our component. This can be observed with
+ the following type declarations:
+
+ type Octal is new Integer range 0 .. 7;
+ type Octal_Array is array (Positive range <>) of Octal;
+ pragma Pack (Octal_Array);
+
+ type Octal_Buffer (Size : Positive) is record
+ Buffer : Octal_Array (1 .. Size);
+ Length : Integer;
+ end record;
+
+ In that case, Buffer is a PAD type whose size is unset and needs
+ to be computed by fixing the unwrapped type.
+
+ Lastly, when should the sub-elements of a type that remained unfixed
+ thus far, be actually fixed?
+
+ The answer is: Only when referencing that element. For instance
+ when selecting one component of a record, this specific component
+ should be fixed at that point in time. Or when printing the value
+ of a record, each component should be fixed before its value gets
+ printed. Similarly for arrays, the element of the array should be
+ fixed when printing each element of the array, or when extracting
+ one element out of that array. On the other hand, fixing should
+ not be performed on the elements when taking a slice of an array!
+
+ Note that one of the side-effects of miscomputing the offset and
+ size of each field is that we end up also miscomputing the size
+ of the containing type. This can have adverse results when computing
+ the value of an entity. GDB fetches the value of an entity based
+ on the size of its type, and thus a wrong size causes GDB to fetch
+ the wrong amount of memory. In the case where the computed size is
+ too small, GDB fetches too little data to print the value of our
+ entiry. Results in this case as unpredicatble, as we usually read
+ past the buffer containing the data =:-o. */
+
+/* Implement the evaluate_exp routine in the exp_descriptor structure
+ for the Ada language. */
+
static struct value *
ada_evaluate_subexp (struct type *expect_type, struct expression *exp,
int *pos, enum noside noside)
@@ -8587,9 +8873,8 @@ ada_evaluate_subexp (struct type *expect_type, struct expression *exp,
}
else
{
- arg1 =
- unwrap_value (evaluate_subexp_standard
- (expect_type, exp, pos, noside));
+ arg1 = evaluate_subexp_standard (expect_type, exp, pos, noside);
+ arg1 = unwrap_value (arg1);
return ada_to_fixed_value (arg1);
}
@@ -8618,6 +8903,12 @@ ada_evaluate_subexp (struct type *expect_type, struct expression *exp,
if (ada_is_packed_array_type (desc_base_type (value_type (argvec[0]))))
argvec[0] = ada_coerce_to_simple_array (argvec[0]);
+ else if (TYPE_CODE (value_type (argvec[0])) == TYPE_CODE_ARRAY
+ && TYPE_FIELD_BITSIZE (value_type (argvec[0]), 0) != 0)
+ /* This is a packed array that has already been fixed, and
+ therefore already coerced to a simple array. Nothing further
+ to do. */
+ ;
else if (TYPE_CODE (value_type (argvec[0])) == TYPE_CODE_REF
|| (TYPE_CODE (value_type (argvec[0])) == TYPE_CODE_ARRAY
&& VALUE_LVAL (argvec[0]) == lval_memory))
@@ -9188,10 +9479,10 @@ ada_evaluate_subexp (struct type *expect_type, struct expression *exp,
return value_zero (ada_aligned_type (type), lval_memory);
}
else
- return
- ada_to_fixed_value (unwrap_value
- (ada_value_struct_elt
- (arg1, &exp->elts[pc + 2].string, 0)));
+ arg1 = ada_value_struct_elt (arg1, &exp->elts[pc + 2].string, 0);
+ arg1 = unwrap_value (arg1);
+ return ada_to_fixed_value (arg1);
+
case OP_TYPE:
/* The value is not supposed to be used. This is here to make it
easier to accommodate expressions that contain types. */
diff --git a/gdb/testsuite/gdb.ada/variant_record_packed_array.exp b/gdb/testsuite/gdb.ada/variant_record_packed_array.exp
new file mode 100644
index 0000000..c8570f0
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/variant_record_packed_array.exp
@@ -0,0 +1,43 @@
+# Copyright 2009 Free Software Foundation, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+if $tracelevel then {
+ strace $tracelevel
+}
+
+load_lib "ada.exp"
+
+set testdir "variant_record_packed_array"
+set testfile "${testdir}/foo"
+set srcfile ${srcdir}/${subdir}/${testfile}.adb
+set binfile ${objdir}/${subdir}/${testfile}
+
+file mkdir ${objdir}/${subdir}/${testdir}
+if {[gdb_compile_ada "${srcfile}" "${binfile}" executable [list debug ]] != "" } {
+ return -1
+}
+
+gdb_exit
+gdb_start
+gdb_reinitialize_dir $srcdir/$subdir
+gdb_load ${binfile}
+
+set bp_location [gdb_get_line_number "START" ${testdir}/foo.adb]
+runto "foo.adb:$bp_location"
+
+gdb_test "print my_buffer" \
+ "= \\(size => 8, buffer => \\(1, 2, 3, 4, 5, 6, 7, 0\\), length => 8\\)" \
+ "print empty"
+
diff --git a/gdb/testsuite/gdb.ada/variant_record_packed_array/foo.adb b/gdb/testsuite/gdb.ada/variant_record_packed_array/foo.adb
new file mode 100644
index 0000000..5e79c4b
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/variant_record_packed_array/foo.adb
@@ -0,0 +1,32 @@
+-- Copyright 2009 Free Software Foundation, Inc.
+--
+-- This program is free software; you can redistribute it and/or modify
+-- it under the terms of the GNU General Public License as published by
+-- the Free Software Foundation; either version 3 of the License, or
+-- (at your option) any later version.
+--
+-- This program is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+-- GNU General Public License for more details.
+--
+-- You should have received a copy of the GNU General Public License
+-- along with this program. If not, see <http://www.gnu.org/licenses/>.
+with Pck; use Pck;
+
+procedure Foo is
+ type Octal is new Integer range 0 .. 7;
+ type Octal_Array is array (Positive range <>) of Octal;
+ pragma Pack (Octal_Array);
+
+ type Octal_Buffer (Size : Positive) is record
+ Buffer : Octal_Array (1 .. Size);
+ Length : Integer;
+ end record;
+
+ My_Buffer : Octal_Buffer (Size => 8);
+begin
+ My_Buffer.Buffer := (1, 2, 3, 4, 5, 6, 7, 0);
+ My_Buffer.Length := My_Buffer.Size;
+ Do_Nothing (My_Buffer'Address); -- START
+end Foo;
diff --git a/gdb/testsuite/gdb.ada/variant_record_packed_array/pck.adb b/gdb/testsuite/gdb.ada/variant_record_packed_array/pck.adb
new file mode 100644
index 0000000..5c61075
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/variant_record_packed_array/pck.adb
@@ -0,0 +1,20 @@
+-- Copyright 2009 Free Software Foundation, Inc.
+--
+-- This program is free software; you can redistribute it and/or modify
+-- it under the terms of the GNU General Public License as published by
+-- the Free Software Foundation; either version 3 of the License, or
+-- (at your option) any later version.
+--
+-- This program is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+-- GNU General Public License for more details.
+--
+-- You should have received a copy of the GNU General Public License
+-- along with this program. If not, see <http://www.gnu.org/licenses/>.
+package body Pck is
+ procedure Do_Nothing (A : System.Address) is
+ begin
+ null;
+ end Do_Nothing;
+end Pck;
diff --git a/gdb/testsuite/gdb.ada/variant_record_packed_array/pck.ads b/gdb/testsuite/gdb.ada/variant_record_packed_array/pck.ads
new file mode 100644
index 0000000..2b8c4c5
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/variant_record_packed_array/pck.ads
@@ -0,0 +1,18 @@
+-- Copyright 2009 Free Software Foundation, Inc.
+--
+-- This program is free software; you can redistribute it and/or modify
+-- it under the terms of the GNU General Public License as published by
+-- the Free Software Foundation; either version 3 of the License, or
+-- (at your option) any later version.
+--
+-- This program is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+-- GNU General Public License for more details.
+--
+-- You should have received a copy of the GNU General Public License
+-- along with this program. If not, see <http://www.gnu.org/licenses/>.
+with System;
+package Pck is
+ procedure Do_Nothing (A : System.Address);
+end Pck;