int nfields, bit_len;
int variant_field;
long off;
- int fld_bit_len, bit_incr;
+ int fld_bit_len;
int f;
/* Compute the number of fields in this record type that are going
if (ada_is_variant_part (type, f))
{
variant_field = f;
- fld_bit_len = bit_incr = 0;
+ fld_bit_len = 0;
}
else if (is_dynamic_field (type, f))
{
field_type = ada_get_base_type (field_type);
field_type = ada_to_fixed_type (field_type, field_valaddr,
field_address, dval, 0);
+ /* If the field size is already larger than the maximum
+ object size, then the record itself will necessarily
+ be larger than the maximum object size. We need to make
+ this check now, because the size might be so ridiculously
+ large (due to an uninitialized variable in the inferior)
+ that it would cause an overflow when adding it to the
+ record size. */
+ check_size (field_type);
TYPE_FIELD_TYPE (rtype, f) = field_type;
TYPE_FIELD_NAME (rtype, f) = TYPE_FIELD_NAME (type, f);
- bit_incr = fld_bit_len =
+ /* The multiplication can potentially overflow. But because
+ the field length has been size-checked just above, and
+ assuming that the maximum size is a reasonable value,
+ an overflow should not happen in practice. So rather than
+ adding overflow recovery code to this already complex code,
+ we just assume that it's not going to happen. */
+ fld_bit_len =
TYPE_LENGTH (TYPE_FIELD_TYPE (rtype, f)) * TARGET_CHAR_BIT;
}
else
TYPE_FIELD_TYPE (rtype, f) = field_type;
TYPE_FIELD_NAME (rtype, f) = TYPE_FIELD_NAME (type, f);
if (TYPE_FIELD_BITSIZE (type, f) > 0)
- bit_incr = fld_bit_len =
+ fld_bit_len =
TYPE_FIELD_BITSIZE (rtype, f) = TYPE_FIELD_BITSIZE (type, f);
else
- bit_incr = fld_bit_len =
+ fld_bit_len =
TYPE_LENGTH (ada_check_typedef (field_type)) * TARGET_CHAR_BIT;
}
if (off + fld_bit_len > bit_len)
bit_len = off + fld_bit_len;
- off += bit_incr;
+ off += fld_bit_len;
TYPE_LENGTH (rtype) =
align_value (bit_len, TARGET_CHAR_BIT) / TARGET_CHAR_BIT;
}
/* The same as ada_to_fixed_type_1, except that it preserves the type
if it is a TYPE_CODE_TYPEDEF of a type that is already fixed.
- ada_to_fixed_type_1 would return the type referenced by TYPE. */
+
+ The typedef layer needs be preserved in order to differentiate between
+ arrays and array pointers when both types are implemented using the same
+ fat pointer. In the array pointer case, the pointer is encoded as
+ a typedef of the pointer type. For instance, considering:
+
+ type String_Access is access String;
+ S1 : String_Access := null;
+
+ To the debugger, S1 is defined as a typedef of type String. But
+ to the user, it is a pointer. So if the user tries to print S1,
+ we should not dereference the array, but print the array address
+ instead.
+
+ If we didn't preserve the typedef layer, we would lose the fact that
+ the type is to be presented as a pointer (needs de-reference before
+ being printed). And we would also use the source-level type name. */
struct type *
ada_to_fixed_type (struct type *type, const gdb_byte *valaddr,
struct type *fixed_type =
ada_to_fixed_type_1 (type, valaddr, address, dval, check_tag);
+ /* If TYPE is a typedef and its target type is the same as the FIXED_TYPE,
+ then preserve the typedef layer.
+
+ Implementation note: We can only check the main-type portion of
+ the TYPE and FIXED_TYPE, because eliminating the typedef layer
+ from TYPE now returns a type that has the same instance flags
+ as TYPE. For instance, if TYPE is a "typedef const", and its
+ target type is a "struct", then the typedef elimination will return
+ a "const" version of the target type. See check_typedef for more
+ details about how the typedef layer elimination is done.
+
+ brobecker/2010-11-19: It seems to me that the only case where it is
+ useful to preserve the typedef layer is when dealing with fat pointers.
+ Perhaps, we could add a check for that and preserve the typedef layer
+ only in that situation. But this seems unecessary so far, probably
+ because we call check_typedef/ada_check_typedef pretty much everywhere.
+ */
if (TYPE_CODE (type) == TYPE_CODE_TYPEDEF
- && TYPE_TARGET_TYPE (type) == fixed_type)
+ && (TYPE_MAIN_TYPE (TYPE_TARGET_TYPE (type))
+ == TYPE_MAIN_TYPE (fixed_type)))
return type;
return fixed_type;
/* TYPE1 might itself be a TYPE_CODE_TYPEDEF (this can happen with
stubs pointing to arrays, as we don't create symbols for array
- types, only for the typedef-to-array types). This is why
- we process TYPE1 with ada_check_typedef before returning
- the result. */
- return ada_check_typedef (type1);
+ types, only for the typedef-to-array types). If that's the case,
+ strip the typedef layer. */
+ if (TYPE_CODE (type1) == TYPE_CODE_TYPEDEF)
+ type1 = ada_check_typedef (type1);
+
+ return type1;
}
}