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/* Copyright (C) 1995,1996 Robert de Bath <rdebath@cix.compulink.co.uk>
* This file is part of the Linux-8086 C library and is distributed
* under the GNU Library General Public License.
*/
#if defined(__AS386_16__) || defined(__AS386_32__)
#define CRT0_OK
/*
* Change of aim here, to allow easy alteration for generation of COM files
* this code has been moved into libc. This means only the linker needs to
* to be told to fetch a different libc the crt0 is unaltered.
*
* This also allows us to deal with __FIRST_ARG_IN_AX__ and __CALLER_SAVES__
* in the same way.
*/
#asm
.text
entry startup ! Crt0 startup
startup:
br ___cstartup
export no_op
no_op: ! Generic no operation call
ret
.ascii __LIBC_VER__ ! Version id.
loc 1 ! Segment 1 is where the pointers to the autostart
! functions are stored.
#if !__AS386_32__
ZP_safety:
.word 0 ! But first some zeros to avoid null pointer writes.
.word 0
.word 0
.word 0
#endif
export auto_start
auto_start:
#endasm
#endif /* __AS386_16__ or __AS386_32__ */
#if defined(__GNUC__) && defined(__i386__)
#ifdef __ELF__
#define CRT0_OK
__asm__(".globl _start\n_start:");
__asm__("jmp __cstartup");
__asm__(".globl __no_op\n__no_op:");
__asm__("ret");
#else
#error This library is for ELF only, sorry.
__asm__(".globl startup\nstartup:");
__asm__("jmp ___cstartup");
__asm__(".globl no_op\nno_op:");
__asm__("ret");
#endif
#endif /* defined(__GNUC__) && defined(__i386__) */
#ifndef CRT0_OK
#error You are not going to get far without crt0.o!
#endif
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