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Q50521: QuickAssembler 2.01 Cannot Debug Code in INCLUDELIB Libraries

Article: Q50521
Product(s): See article
Version(s): 2.01
Operating System(s): MS-DOS
Keyword(s): ENDUSER | buglist2.01 | mspl13_masm
Last Modified: 18-DEC-1989

Due to the INCLUDELIB directive, the QuickAssembler cannot debug
source code in libraries that are linked in. When tracing into the
library that is included with the directive, the debugger stops
execution of the program and reassembles the source for the library
routine. This is not the expected behavior of the assembler/debugger,
but the following workarounds are quite simple.

The first option is to debug the library routine before placing it in
the library. To do this, include the file in the program list, which
then links the object file instead of the library. In this form, the
routine can be traced into and the code can be debugged. When the
modules have been debugged, they can then be included in a library
that is linked in by use of the INCLUDELIB directive. After the
routines are included in the library, use the F10 key to step over the
calls to routines in the library. This executes the routine without
trying to display the source for it.

Another workaround is to put the library in the program list instead
of using INCLUDELIB. By including the library in the program list,
QuickAssembler will debug source code that is in the library routine.
Therefore, you can trace into the source code (even when it is
included in a library) without problem. Use this option if you want to
trace into any function in your program (meaning routines in both
object modules and libraries.

Microsoft has confirmed this to be a problem with QuickAssembler
Version 2.01. We are researching this problem and will post new
information as it becomes available.

Below is a sample program (consisting of two files) that demonstrates
the problem:

******** FILE 1 ********

;  HELLO.ASM
;
;  This is a simple hello world program that will use
;  both DOS display string and DOS Write functions.

TITLE  HELLO
DOSSEG
; Uncomment the following INCLUDELIB statement, then step through the
; CALL WRT line to step into the code for WRT. This will cause the
; problem.
;INCLUDELIB wrt.lib
.MODEL SMALL
.DATA
MSG      DB   "Hello World",0Dh,0Ah,24h

.STACK 800H

.CODE
                EXTRN WRT:PROC
.STARTUP
                PUSH  DX
                PUSH  CX
                PUSH  BX

                MOV   AH, 09h           ; DOS DISPLAY STRING
                MOV   DX, OFFSET MSG    ; ADDRESS OF STRING
                INT   21h

                CALL  WRT               ; MAKE THE WRITE CALL!

    XOR   AL,AL             ; SET UP RETURN CODE
.EXIT
                END

******** FILE 2 ********

; WRT.ASM
;
; Assemble this file and put it into a library called WRT.LIB. (This
; can be done by typing LIB WRT.LIB+WRT.OBJ; after you have assembled
; WRT.ASM.
;
; This file MUST be linked to the above program to avoid unresolved
; externals. Either link the .OBJ file or the .LIB file with a program
; list, OR uncomment the INCLUDELIB directive above.

TITLE  WRT
DOSSEG
.MODEL SMALL
.DATA
MYNAME   DB   "John Smith",0Dh, 0Ah,24h
LNAME    EQU  $-MYNAME-1

.CODE
PUBLIC WRT
WRT   PROC
                MOV   AH, 40h           ; DOS WRITE FUNCTION
                MOV   BX, 01h           ; HANDLE FOR STDOUT
                MOV   CX, LNAME         ; NUMBER OF CHARACTER TO WRITE
                MOV   DX, OFFSET MYNAME ; OFFSET OF STRING TO PRINT
                INT   21h

                RET
WRT   ENDP
                END

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