[Geekos-devel] undefined reference to __bss_start

[Ahmad R. <ahm...@ho...>]

Hi,

I am trying to make project 0, where I get an 'undefined reference to 
__bss_start':

geekos/mem.o(.text+0x3bf): In function `Init_BSS':
./src/geekos/mem.c:173: undefined reference to `__bss_start'
geekos/mem.o(.text+0x3c7):../src/geekos/mem.c:173: undefined reference to 
`__bss_start'
make.exe: *** [geekos/kernel.exe] Error 1

My environment is: windows (im trying to make geekos work on win, and i 
removed all errors except this one), and the djgpp compiler (it is gcc for 
dos). The error is caused by the reference in mem.c:

void Init_BSS(void)
{
    extern char BSS_END, BSS_START;
    /* Fill .bss with zeroes */
    memset(&BSS_START, '\0', &BSS_END - &BSS_START);
}

I did a little search, and the variable BSS_START is not defined in any src 
file.
I would like to know if the variable should be provided by the compiler. It 
seems to be a mystery!
Please shed some light on the situation.

Apologies if this question has been asked before.

Thanks,
Ahmad