From:	"David Lee" <keeyu AT poetic DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	GDB problem:
Date:	Sat, 15 Jul 2000 00:52:12 +0800
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To:	djgpp AT delorie DOT com
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Reply-To:	djgpp AT delorie DOT com

I write a little program:

#include <sys/farptr.h>
#include <dpmi.h>

void main()
{
    int sel, seg;
    seg = __dpmi_allocate_dos_memory(1, &sel);

    _farpokeb(sel, 0, 2);
    _farpokeb(sel, 1, 29);
    _farpokeb(sel, 2, 112);
    _farpokeb(sel, 3, 2);

    __dpmi_free_dos_memory(sel);
}

Then I do the following:

C:\> gxx -g test.cpp
C:\> gdb a.exe

(gdb) b main        // set breakpoint in main()
(gdb) run              // run the program
(gdb) s                  // step
Breakpoint 1, main () at dos.cpp:9
9               seg = __dpmi_allocate_dos_memory(12, &sel);
Current language:  auto; currently c++
(gdb) s
11              _farpokeb(sel, 0, 2);
(gdb) s
_farpokeb (selector=287, offset=0, value=2) at test.cpp:89
Line number 89 out of range; test.cpp has 17 lines.
(gdb)

It says that "Line number 89 out of range". But why would gdb goto
line 89? My source code does not even have line 89!

Any help is appreciated.

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