re PR middle-end/28865 (Structures with a flexible arrray member have wrong .size)
PR middle-end/28865
* varasm.c (output_constant): Return the number of bytes actually
emitted.
(output_constructor_array_range): Update the field size with the
number of bytes emitted by output_constant.
(output_constructor_regular_field): Likewise. Also do not
complain if the total number of bytes emitted is now greater
than the expected fieldpos.
* output.h (output_constant): Update prototype and descriptive
comment.