Q34667: No Warning on Immediate Value Out of Range

Article: Q34667
Product(s): See article
Version(s): 5.10   | 5.10
Operating System(s): MS-DOS | OS/2
Keyword(s): ENDUSER | | mspl13_masm
Last Modified: 12-JAN-1989

In the following instruction MASM doesn't warn that an immediate value
is too large:

add structure.element[edi],immediate value

The element is byte wide, but the immediate value is much larger than
256. The assembler creates a byte add instruction, silently truncating
the high part of the immediate value.

MASM generally generates error messages on values out of range. MASM
does not generate an out of range error message when the immediate
value could be a signed number (e.g. 0ffffff75h) that is -8bH. The
assembler can't tell if the immediate value is a negative number or an
unsigned number that is out of bounds. In this case, MASM will not
generate an error message.

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