Hi all, In gpc.pas, in the declaration { 8086 CPU registers -- only used by the unportable Dos routines } Registers = record case Boolean of False : (AX, BX, CX, DX, BP, SI, DI, DS, ES, Flags : Word); True : (AL, AH, BL, BH, CL, CH, DL, DH : Byte) end; Word should be replaced by Word16. It is the same if one defines __BP_TYPE_SIZES__ but not otherwise. The alignment between X and H+L is then lost, and this triggered a bug in a program for which I prefer gpc type sizes for mainstream computations, but which uses incidentally a unit which comes from old BP stuff and calls a msdos interrupt. Hope this helps Maurice -- Maurice Lombardi Laboratoire de Spectrometrie Physique, Universite Joseph Fourier de Grenoble, BP87 38402 Saint Martin d'Heres Cedex FRANCE Tel: 33 (0)4 76 51 47 51 Fax: 33 (0)4 76 51 45 44 mailto:Maurice.Lombardi@ujf-grenoble.fr