Microsoft KB Archive/35114
Article ID: 35114
Article Last Modified on 10/17/2003
- Microsoft Macro Assembler 5.1 Standard Edition
- Microsoft Macro Assembler 5.1a
- Microsoft Macro Assembler 6.0 Standard Edition
- Microsoft Macro Assembler 6.0a
- Microsoft Macro Assembler 6.0b
This article was previously published under Q35114
The comparison of a constant and a relocatable is not allowed. The following example demonstrates three approaches to comparing a constant and a relocatable. In the Microsoft Macro Assembler (MASM) 5.1 and 5.1a you will get the warning:
on the first of these approaches. In MASM 6.0, 6.0a, and 6.0b you will get the error:
on the first of these approaches, and you will get the error:
on the second. The third approach, which turns the relocatable into a constant by subtracting the beginning of the segment, will work.
You can not compare a constant to a relocatable at assembly time because the linker may change the value of the relocatable at link time.
This is the expected behavior of MASM. The third approach in the example below demonstrates the prefered way to compare a constant and a relocatable.
; Assemble options needed: none _DATA SEGMENT 'DATA' a_var DW ? .ERRNZ 08000h LT a_var ; constant LT relocatable .ERRNZ _DATA:08000h LT a_var ; cast constant to relocatable .ERRNZ 08000h LT a_var- @CurSeg ; difference of relocatables _DATA ENDS END
Additional query words: 5.10 5.10a 6.00 6.00a 6.00b