DOCUMENT:Q24953  06-MAY-2001  [masm]
TITLE   :Phase Errors May Be Caused By Forward References
PRODUCT :Microsoft Macro Assembler
PROD/VER::1.25,1.27,3.0x,4.0,5.0,5.1
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Macro Assembler (MASM), versions 1.25, 1.27, 3.0x, 4.0, 5.0, 5.1 
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SUMMARY
=======

Phase errors indicate that a relative address of a label changed between pass 1
and pass 2 of the assembly process. They usually are caused by improper forward
references to labels. During pass 1, the assembler will have to make assumptions
(e.g. it might assume a near jump during pass 1 if the location of a label is
not known). During pass 2, the assembler may have to change those assumptions
(e.g. now it knows that the jump is to a far label). If this involves changing
the size of an instruction, that difference can cause a phase error.

To examine the assumptions made by the assembler on pass 1, use the /D option to
get a pass 1 listing.

MORE INFORMATION
================

Phase errors can usually be prevented by using segment overrides or explicit
type specification, as shown in the following examples:

      jmp dword ptr far_label         ;jump to far label

      mov ax, word ptr label

Additional query words: 1.25 1.27 3.0x 4.00 5.00 5.10

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Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM510 kbMASM125 kbMASM127 kbMASM30xSearch kbMASM400 kbMASM500
Version           : :1.25,1.27,3.0x,4.0,5.0,5.1

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