/* Compute the offset of the containing object in bytes. */
object_offset_in_bytes = object_offset_in_align_units * type_align_in_bytes;
+ /* The above code assumes that the field does not cross an alignment
+ boundary. This can happen if PCC_BITFIELD_TYPE_MATTERS is not defined,
+ or if the structure is packed. If this happens, then we get an object
+ which starts after the bitfield, which means that the bit offset is
+ negative. Gdb fails when given negative bit offsets. We avoid this
+ by recomputing using the first bit of the bitfield. This will give
+ us an object which does not completely contain the bitfield, but it
+ will be aligned, and it will contain the first bit of the bitfield. */
+ if (object_offset_in_bits > bitpos_int)
+ {
+ deepest_bitpos = bitpos_int + 1;
+ object_offset_in_bits
+ = ceiling (deepest_bitpos, type_align_in_bits) - type_size_in_bits;
+ object_offset_in_align_units = (object_offset_in_bits
+ / type_align_in_bits);
+ object_offset_in_bytes = (object_offset_in_align_units
+ * type_align_in_bytes);
+ }
+
return object_offset_in_bytes;
}