PR fortran/99205 - Out of memory with undefined character length

PR fortran/99205 - Out of memory with undefined character length

A character variable appearing as a data statement object cannot
be automatic, thus it shall have constant length.

gcc/fortran/ChangeLog:

	PR fortran/99205
	* data.c (gfc_assign_data_value): Reject non-constant character
	length for lvalue.
	* trans-array.c (gfc_conv_array_initializer): Restrict loop to
	elements which are defined to avoid NULL pointer dereference.

gcc/testsuite/ChangeLog:

	PR fortran/99205
	* gfortran.dg/data_char_4.f90: New test.
	* gfortran.dg/data_char_5.f90: New test.