Date: Mon, 25 Jul 94 10:10:13 EDT
From: hvb AT netrix DOT com
To: djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: Help with djgpp 1.11 build
Reply-To: hvb AT netrix DOT com

Dear all,

I recently encountered a problem when trying to build the debuggers to
use with go32 version 1.11. I built these debuggers with gcc 2.57
(came with the djgpp 1.11 package), but go32 reported a segmentation
violation when it loaded them.  (I obtained djgpp version 1.11
including the five patches m1 to m5 from oak.oakland.edu).

Segmentation violation in pointer 0xa018e0e7 at d8:900000a8

( That's the value of tss_ptr->tss_eip after the external
  debugger was loaded. )

eax=00387088 ebx=e00b8000 ecx=00000000 edx=0001cfe8 
esi=0000002a edi=e001e075
ebp=e00b8000 esp=9ffffff4 cs=d8 ds=48 es=48 fs=48 gs=38 
ss=48 cr2=0000e0e7

Call frame taceback EIPs:
  0x900000a8
  0x076c076f

- Size of edebug32 after striped  : 49,232 Bytes.
- Size of edebug32 before striped : 111,750 Bytes.
- Size of original edebug32       : 49,152 Bytes.

The error occurred in either case, no matter if the file
was striped or not. The source has not been modified, nor 
was the makefile, except for the library path. The content of
the makefile that I used is:

>>CFLAGS = -I.. -O2 -g -Wformat
>>
>>EO = \
>>        ed.o\
>>        debug.o\
>>        unassmbl.o\
>>        $E
>>
>>CO = \
>>        syms.o\
>>        wild.o\
>>        $E
>>
>>.c.o:
>>        gcc $(CFLAGS) -c $*.c
>>
>>LIB=/djgpp111/lib
>>
>>all : edebug32 ed32-dpmi symify.exe
>>
>>edebug32 : $(EO) $(CO)
>>        ld -Ttext 0x900000a8 -N -o edebug32 $(LIB)/crt0.o 
>>        $(EO) $(CO) $(LIB)/libc.a
>>
>>ed32-dpmi : $(EO) $(CO)
>>        ld -Ttext 0x000000a8 -N -o ed32-dpmi $(LIB)/crt0.o 
>>        $(EO) $(CO) $(LIB)/libc.a
>>
>>symify.exe : symify.o $(CO)
>>        gcc -o symify symify.o $(CO) -lpc
>>        strip symify
>>        coff2exe symify
>>        -del symify
>>
>>clean :
>>        -del *.o
>>        -del edebug32
>>        -del ed32-dpmi
>>        -del symify.exe
>>
>># DEPENDENCIES
>>
>>unassmbl.o : ed.h ../gotypes.h ../tss.h ../extdebug.h 
>>             unassmbl.h syms.h
>>
>>debug.o : ed.h ../extdebug.h ../tss.h ../gotypes.h 
>>             unassmbl.h syms.h
>>
>>syms.o : ed.h ../extdebug.h ../tss.h ../gotypes.h coff.h 
>>             syms.h stab.h
>>
>>symsaout.o : ed.h ../extdebug.h ../tss.h ../gotypes.h
>>
>>ed.o : ed.h ../extdebug.h ../tss.h ../gotypes.h ../paging.h 
>>             unassmbl.h debug.h
>>
>>symify.o : ed.h ../extdebug.h ../tss.h ../gotypes.h syms.h


More over, the a.out files that gcc 2.57  produced did not 
seems to have a correct symbols table (as when debug32 tried
to load one, it took it 1/2 hours to load more than 1,600,000 
symbols just to reported: "Undefined symbol _main" (The a.out 
file was about 16K, and contained only one printf statement.)

However, the other debugger that comes with go32, gdb 4.12 is
capable of reading a djgcc compiled file, but not a UNIX
gcc compiled and linked file (It reported: 
"c:/djgpp111/dgb32/xps_386.abs": not in executable format.
File format not recognized.) 
But when it loaded the a.out file, there is no way to set 
breakpoints or start that program since no symbol table 
was loaded.

Therefore, I have the following questions:

1. Which version of djgcc compiler I should use to build
   v1.11 stuff.

2. If djgcc is capable of making such a file, what compiler
   directive(s) should I use to make that file compatible
   with go32 / debug32 / gdb?

3. How can I load a UNIX gcc compiled file into gdb?

Thanks


==============================================================
Hung Bui                           Internet: hvb AT netrix DOT com
Netrix Corporation                    Phone: +1 703 793 1016
13595 Dulles Technology Drive           Fax: +1 703 713 3805
Herndon Va 22071
==============================================================