DOCUMENT:Q69540 06-MAY-2001 [masm] TITLE :JMP to a Far Address Lists Segment First in Listing File PRODUCT :Microsoft Macro Assembler PROD/VER::6.0,6.0a,6.0b,6.1,6.11,6.1a OPER/SYS: KEYWORDS: ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Macro Assembler (MASM), versions 6.0, 6.0a, 6.0b, 6.1, 6.1a, 6.11 ------------------------------------------------------------------------------- SUMMARY ======= In the Macro Assembler (MASM) version 6.0 and later, the opcode for a JMP to a far address is shown in the listing file with the segment first, then the offset. In the actual .OBJ file, the address is stored in the reversed order (offset then segment). MORE INFORMATION ================ The following is the encoding for the JMP instruction from the listing (.LST) file generated from the sample program below: 0000 EA ---- 0000 E jmp faddr The above address for faddr (---- 0000) is displayed with the segment listed first (----), then the offset(0000). Because the linker resolves this address at link time, the actual segment and offset is not known at assemble time, and is not listed in this file. If you then look at the actual .OBJ or .EXE file produced by the above code (by using CodeView, for example), you will see the offset first in the file, then the segment. This is expected behavior with MASM version 6.0 and later and is designed to make the segment:offset more readable. This is different from MASM version 5.1, which displayed the addresses for far JMP instructions in the reversed (offset then segment) form. Sample Code ----------- ; Assemble options needed: /c /Fl .MODEL large EXTRN faddr:far .CODE jmp faddr END Additional query words: kbinf 6.00 6.00a 6.00b 6.10 6.10a jump object ====================================================================== Keywords : Technology : kbMASMsearch kbAudDeveloper kbMASM600 kbMASM610 kbMASM611 kbMASM610a kbMASM600a kbMASM600b Version : :6.0,6.0a,6.0b,6.1,6.11,6.1a ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2001.