Microsoft KB Archive/26813

DR4 and DR5 ID Number: Q26813

5.00 MS-DOS buglist5.00

Problem: MASM allows MOVs into/from DR4 and DR5 even though these are marked as “reserved” by INTEL. MASM correctly flags attempts to address TRO-5 which is also marked as reserved.

Response: This problem was fixed in MASM Version 5.00A. Please call Product Support and request an update to MASM Version 5.00A.