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https://github.com/netwide-assembler/nasm.git
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934 lines
25 KiB
C
934 lines
25 KiB
C
/* outaout.c output routines for the Netwide Assembler to produce
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* Linux a.out object files
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*
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* The Netwide Assembler is copyright (C) 1996 Simon Tatham and
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* Julian Hall. All rights reserved. The software is
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* redistributable under the licence given in the file "Licence"
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* distributed in the NASM archive.
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <ctype.h>
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#include "nasm.h"
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#include "nasmlib.h"
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#include "outform.h"
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#if defined OF_AOUT || defined OF_AOUTB
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#define RELTYPE_ABSOLUTE 0x00
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#define RELTYPE_RELATIVE 0x01
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#define RELTYPE_GOTPC 0x01 /* no explicit GOTPC in a.out */
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#define RELTYPE_GOTOFF 0x10
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#define RELTYPE_GOT 0x10 /* distinct from GOTOFF bcos sym not sect */
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#define RELTYPE_PLT 0x21
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#define RELTYPE_SYMFLAG 0x08
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struct Reloc {
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struct Reloc *next;
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long address; /* relative to _start_ of section */
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long symbol; /* symbol number or -ve section id */
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int bytes; /* 2 or 4 */
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int reltype; /* see above */
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};
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struct Symbol {
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long strpos; /* string table position of name */
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int type; /* symbol type - see flags below */
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long value; /* address, or COMMON variable size */
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long size; /* size for data or function exports */
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long segment; /* back-reference used by gsym_reloc */
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struct Symbol *next; /* list of globals in each section */
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struct Symbol *nextfwd; /* list of unresolved-size symbols */
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char *name; /* for unresolved-size symbols */
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long symnum; /* index into symbol table */
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};
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/*
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* Section IDs - used in Reloc.symbol when negative, and in
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* Symbol.type when positive.
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*/
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#define SECT_ABS 2 /* absolute value */
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#define SECT_TEXT 4 /* text section */
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#define SECT_DATA 6 /* data section */
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#define SECT_BSS 8 /* bss section */
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#define SECT_MASK 0xE /* mask out any of the above */
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/*
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* More flags used in Symbol.type.
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*/
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#define SYM_GLOBAL 1 /* it's a global symbol */
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#define SYM_DATA 0x100 /* used for shared libs */
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#define SYM_FUNCTION 0x200 /* used for shared libs */
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#define SYM_WITH_SIZE 0x4000 /* not output; internal only */
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/*
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* Bit more explanation of symbol types: SECT_xxx denotes a local
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* symbol. SECT_xxx|SYM_GLOBAL denotes a global symbol, defined in
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* this module. Just SYM_GLOBAL, with zero value, denotes an
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* external symbol referenced in this module. And just SYM_GLOBAL,
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* but with a non-zero value, declares a C `common' variable, of
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* size `value'.
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*/
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struct Section {
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struct SAA *data;
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unsigned long len, size, nrelocs;
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long index;
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struct Reloc *head, **tail;
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struct Symbol *gsyms, *asym;
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};
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static struct Section stext, sdata, sbss;
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static struct SAA *syms;
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static unsigned long nsyms;
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static struct RAA *bsym;
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static struct SAA *strs;
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static unsigned long strslen;
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static struct Symbol *fwds;
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static FILE *aoutfp;
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static efunc error;
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static evalfunc evaluate;
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static int bsd;
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static int is_pic;
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static void aout_write(void);
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static void aout_write_relocs(struct Reloc *);
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static void aout_write_syms(void);
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static void aout_sect_write(struct Section *, unsigned char *, unsigned long);
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static void aout_pad_sections(void);
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static void aout_fixup_relocs(struct Section *);
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/*
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* Special section numbers which are used to define special
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* symbols, which can be used with WRT to provide PIC relocation
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* types.
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*/
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static long aout_gotpc_sect, aout_gotoff_sect;
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static long aout_got_sect, aout_plt_sect;
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static long aout_sym_sect;
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static void aoutg_init(FILE *fp, efunc errfunc, ldfunc ldef, evalfunc eval)
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{
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aoutfp = fp;
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error = errfunc;
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evaluate = eval;
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(void) ldef; /* placate optimisers */
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stext.data = saa_init(1L); stext.head = NULL; stext.tail = &stext.head;
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sdata.data = saa_init(1L); sdata.head = NULL; sdata.tail = &sdata.head;
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stext.len = stext.size = sdata.len = sdata.size = sbss.len = 0;
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stext.nrelocs = sdata.nrelocs = 0;
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stext.gsyms = sdata.gsyms = sbss.gsyms = NULL;
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stext.index = seg_alloc();
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sdata.index = seg_alloc();
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sbss.index = seg_alloc();
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stext.asym = sdata.asym = sbss.asym = NULL;
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syms = saa_init((long)sizeof(struct Symbol));
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nsyms = 0;
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bsym = raa_init();
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strs = saa_init(1L);
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strslen = 0;
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fwds = NULL;
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}
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#ifdef OF_AOUT
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static void aout_init(FILE *fp, efunc errfunc, ldfunc ldef, evalfunc eval)
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{
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bsd = FALSE;
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aoutg_init (fp, errfunc, ldef, eval);
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aout_gotpc_sect = aout_gotoff_sect = aout_got_sect =
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aout_plt_sect = aout_sym_sect = NO_SEG;
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}
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#endif
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#ifdef OF_AOUTB
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extern struct ofmt of_aoutb;
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static void aoutb_init(FILE *fp, efunc errfunc, ldfunc ldef, evalfunc eval)
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{
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bsd = TRUE;
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aoutg_init (fp, errfunc, ldef, eval);
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is_pic = 0x00; /* may become 0x40 */
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aout_gotpc_sect = seg_alloc();
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ldef("..gotpc", aout_gotpc_sect+1, 0L, NULL, FALSE,FALSE,&of_aoutb,error);
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aout_gotoff_sect = seg_alloc();
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ldef("..gotoff", aout_gotoff_sect+1, 0L,NULL,FALSE,FALSE,&of_aoutb,error);
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aout_got_sect = seg_alloc();
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ldef("..got", aout_got_sect+1, 0L, NULL, FALSE,FALSE,&of_aoutb,error);
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aout_plt_sect = seg_alloc();
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ldef("..plt", aout_plt_sect+1, 0L, NULL, FALSE,FALSE,&of_aoutb,error);
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aout_sym_sect = seg_alloc();
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ldef("..sym", aout_sym_sect+1, 0L, NULL, FALSE,FALSE,&of_aoutb,error);
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}
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#endif
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static void aout_cleanup(int debuginfo)
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{
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struct Reloc *r;
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(void) debuginfo;
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aout_pad_sections();
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aout_fixup_relocs(&stext);
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aout_fixup_relocs(&sdata);
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aout_write();
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fclose (aoutfp);
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saa_free (stext.data);
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while (stext.head) {
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r = stext.head;
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stext.head = stext.head->next;
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nasm_free (r);
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}
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saa_free (sdata.data);
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while (sdata.head) {
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r = sdata.head;
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sdata.head = sdata.head->next;
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nasm_free (r);
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}
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saa_free (syms);
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raa_free (bsym);
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saa_free (strs);
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}
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static long aout_section_names (char *name, int pass, int *bits)
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{
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/*
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* Default to 32 bits.
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*/
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if (!name)
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*bits = 32;
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if (!name)
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return stext.index;
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if (!strcmp(name, ".text"))
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return stext.index;
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else if (!strcmp(name, ".data"))
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return sdata.index;
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else if (!strcmp(name, ".bss"))
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return sbss.index;
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else
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return NO_SEG;
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}
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static void aout_deflabel (char *name, long segment, long offset,
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int is_global, char *special)
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{
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int pos = strslen+4;
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struct Symbol *sym;
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int special_used = FALSE;
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if (name[0] == '.' && name[1] == '.' && name[2] != '@') {
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/*
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* This is a NASM special symbol. We never allow it into
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* the a.out symbol table, even if it's a valid one. If it
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* _isn't_ a valid one, we should barf immediately.
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*/
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if (strcmp(name, "..gotpc") && strcmp(name, "..gotoff") &&
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strcmp(name, "..got") && strcmp(name, "..plt") &&
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strcmp(name, "..sym"))
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error (ERR_NONFATAL, "unrecognised special symbol `%s'", name);
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return;
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}
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if (is_global == 3) {
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struct Symbol **s;
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/*
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* Fix up a forward-reference symbol size from the first
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* pass.
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*/
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for (s = &fwds; *s; s = &(*s)->nextfwd)
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if (!strcmp((*s)->name, name)) {
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struct tokenval tokval;
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expr *e;
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char *p = special;
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while (*p && !isspace(*p)) p++;
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while (*p && isspace(*p)) p++;
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stdscan_reset();
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stdscan_bufptr = p;
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tokval.t_type = TOKEN_INVALID;
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e = evaluate(stdscan, NULL, &tokval, NULL, 1, error, NULL);
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if (e) {
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if (!is_simple(e))
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error (ERR_NONFATAL, "cannot use relocatable"
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" expression as symbol size");
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else
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(*s)->size = reloc_value(e);
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}
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/*
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* Remove it from the list of unresolved sizes.
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*/
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nasm_free ((*s)->name);
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*s = (*s)->nextfwd;
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return;
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}
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return; /* it wasn't an important one */
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}
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saa_wbytes (strs, name, (long)(1+strlen(name)));
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strslen += 1+strlen(name);
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sym = saa_wstruct (syms);
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sym->strpos = pos;
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sym->type = is_global ? SYM_GLOBAL : 0;
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sym->segment = segment;
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if (segment == NO_SEG)
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sym->type |= SECT_ABS;
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else if (segment == stext.index) {
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sym->type |= SECT_TEXT;
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if (is_global) {
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sym->next = stext.gsyms;
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stext.gsyms = sym;
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} else if (!stext.asym)
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stext.asym = sym;
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} else if (segment == sdata.index) {
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sym->type |= SECT_DATA;
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if (is_global) {
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sym->next = sdata.gsyms;
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sdata.gsyms = sym;
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} else if (!sdata.asym)
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sdata.asym = sym;
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} else if (segment == sbss.index) {
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sym->type |= SECT_BSS;
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if (is_global) {
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sym->next = sbss.gsyms;
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sbss.gsyms = sym;
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} else if (!sbss.asym)
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sbss.asym = sym;
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} else
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sym->type = SYM_GLOBAL;
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if (is_global == 2)
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sym->value = offset;
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else
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sym->value = (sym->type == SYM_GLOBAL ? 0 : offset);
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if (is_global && sym->type != SYM_GLOBAL) {
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/*
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* Global symbol exported _from_ this module. We must check
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* the special text for type information.
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*/
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if (special) {
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int n = strcspn(special, " ");
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if (!nasm_strnicmp(special, "function", n))
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sym->type |= SYM_FUNCTION;
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else if (!nasm_strnicmp(special, "data", n) ||
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!nasm_strnicmp(special, "object", n))
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sym->type |= SYM_DATA;
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else
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error(ERR_NONFATAL, "unrecognised symbol type `%.*s'",
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n, special);
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if (special[n]) {
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struct tokenval tokval;
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expr *e;
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int fwd = FALSE;
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char *saveme=stdscan_bufptr; /* bugfix? fbk 8/10/00 */
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if (!bsd) {
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error(ERR_NONFATAL, "Linux a.out does not support"
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" symbol size information");
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} else {
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while (special[n] && isspace(special[n]))
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n++;
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/*
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* We have a size expression; attempt to
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* evaluate it.
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*/
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sym->type |= SYM_WITH_SIZE;
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stdscan_reset();
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stdscan_bufptr = special+n;
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tokval.t_type = TOKEN_INVALID;
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e = evaluate(stdscan, NULL, &tokval, &fwd, 0, error, NULL);
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if (fwd) {
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sym->nextfwd = fwds;
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fwds = sym;
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sym->name = nasm_strdup(name);
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} else if (e) {
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if (!is_simple(e))
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error (ERR_NONFATAL, "cannot use relocatable"
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" expression as symbol size");
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else
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sym->size = reloc_value(e);
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}
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}
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stdscan_bufptr=saveme; /* bugfix? fbk 8/10/00 */
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}
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special_used = TRUE;
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}
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}
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/*
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* define the references from external-symbol segment numbers
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* to these symbol records.
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*/
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if (segment != NO_SEG && segment != stext.index &&
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segment != sdata.index && segment != sbss.index)
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bsym = raa_write (bsym, segment, nsyms);
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sym->symnum = nsyms;
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nsyms++;
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if (sym->type & SYM_WITH_SIZE)
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nsyms++; /* and another for the size */
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if (special && !special_used)
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error(ERR_NONFATAL, "no special symbol features supported here");
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}
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static void aout_add_reloc (struct Section *sect, long segment,
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int reltype, int bytes)
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{
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struct Reloc *r;
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r = *sect->tail = nasm_malloc(sizeof(struct Reloc));
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sect->tail = &r->next;
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r->next = NULL;
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r->address = sect->len;
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r->symbol = (segment == NO_SEG ? -SECT_ABS :
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segment == stext.index ? -SECT_TEXT :
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segment == sdata.index ? -SECT_DATA :
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segment == sbss.index ? -SECT_BSS :
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raa_read(bsym, segment));
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r->reltype = reltype;
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if (r->symbol >= 0)
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r->reltype |= RELTYPE_SYMFLAG;
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r->bytes = bytes;
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sect->nrelocs++;
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}
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/*
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* This routine deals with ..got and ..sym relocations: the more
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* complicated kinds. In shared-library writing, some relocations
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* with respect to global symbols must refer to the precise symbol
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* rather than referring to an offset from the base of the section
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* _containing_ the symbol. Such relocations call to this routine,
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* which searches the symbol list for the symbol in question.
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*
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* RELTYPE_GOT references require the _exact_ symbol address to be
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* used; RELTYPE_ABSOLUTE references can be at an offset from the
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* symbol. The boolean argument `exact' tells us this.
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*
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* Return value is the adjusted value of `addr', having become an
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* offset from the symbol rather than the section. Should always be
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* zero when returning from an exact call.
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*
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* Limitation: if you define two symbols at the same place,
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* confusion will occur.
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*
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* Inefficiency: we search, currently, using a linked list which
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* isn't even necessarily sorted.
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*/
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static long aout_add_gsym_reloc (struct Section *sect,
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long segment, long offset,
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int type, int bytes, int exact)
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{
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struct Symbol *sym, *sm, *shead;
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struct Reloc *r;
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/*
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* First look up the segment to find whether it's text, data,
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* bss or an external symbol.
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*/
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shead = NULL;
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if (segment == stext.index)
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shead = stext.gsyms;
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else if (segment == sdata.index)
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shead = sdata.gsyms;
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else if (segment == sbss.index)
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shead = sbss.gsyms;
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if (!shead) {
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if (exact && offset != 0)
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error (ERR_NONFATAL, "unable to find a suitable global symbol"
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" for this reference");
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else
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aout_add_reloc (sect, segment, type, bytes);
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return offset;
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}
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if (exact) {
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/*
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* Find a symbol pointing _exactly_ at this one.
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*/
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for (sym = shead; sym; sym = sym->next)
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if (sym->value == offset)
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break;
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} else {
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/*
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* Find the nearest symbol below this one.
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*/
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sym = NULL;
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for (sm = shead; sm; sm = sm->next)
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if (sm->value <= offset && (!sym || sm->value > sym->value))
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sym = sm;
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}
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if (!sym && exact) {
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error (ERR_NONFATAL, "unable to find a suitable global symbol"
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" for this reference");
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return 0;
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}
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r = *sect->tail = nasm_malloc(sizeof(struct Reloc));
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sect->tail = &r->next;
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r->next = NULL;
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r->address = sect->len;
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r->symbol = sym->symnum;
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r->reltype = type | RELTYPE_SYMFLAG;
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r->bytes = bytes;
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sect->nrelocs++;
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return offset - sym->value;
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}
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/*
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* This routine deals with ..gotoff relocations. These _must_ refer
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* to a symbol, due to a perversity of *BSD's PIC implementation,
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* and it must be a non-global one as well; so we store `asym', the
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* first nonglobal symbol defined in each section, and always work
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* from that. Relocation type is always RELTYPE_GOTOFF.
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*
|
|
* Return value is the adjusted value of `addr', having become an
|
|
* offset from the `asym' symbol rather than the section.
|
|
*/
|
|
static long aout_add_gotoff_reloc (struct Section *sect, long segment,
|
|
long offset, int bytes)
|
|
{
|
|
struct Reloc *r;
|
|
struct Symbol *asym;
|
|
|
|
/*
|
|
* First look up the segment to find whether it's text, data,
|
|
* bss or an external symbol.
|
|
*/
|
|
asym = NULL;
|
|
if (segment == stext.index)
|
|
asym = stext.asym;
|
|
else if (segment == sdata.index)
|
|
asym = sdata.asym;
|
|
else if (segment == sbss.index)
|
|
asym = sbss.asym;
|
|
if (!asym)
|
|
error (ERR_NONFATAL, "`..gotoff' relocations require a non-global"
|
|
" symbol in the section");
|
|
|
|
r = *sect->tail = nasm_malloc(sizeof(struct Reloc));
|
|
sect->tail = &r->next;
|
|
r->next = NULL;
|
|
|
|
r->address = sect->len;
|
|
r->symbol = asym->symnum;
|
|
r->reltype = RELTYPE_GOTOFF;
|
|
r->bytes = bytes;
|
|
|
|
sect->nrelocs++;
|
|
|
|
return offset - asym->value;
|
|
}
|
|
|
|
static void aout_out (long segto, void *data, unsigned long type,
|
|
long segment, long wrt)
|
|
{
|
|
struct Section *s;
|
|
long realbytes = type & OUT_SIZMASK;
|
|
long addr;
|
|
unsigned char mydata[4], *p;
|
|
|
|
type &= OUT_TYPMASK;
|
|
|
|
/*
|
|
* handle absolute-assembly (structure definitions)
|
|
*/
|
|
if (segto == NO_SEG) {
|
|
if (type != OUT_RESERVE)
|
|
error (ERR_NONFATAL, "attempt to assemble code in [ABSOLUTE]"
|
|
" space");
|
|
return;
|
|
}
|
|
|
|
if (segto == stext.index)
|
|
s = &stext;
|
|
else if (segto == sdata.index)
|
|
s = &sdata;
|
|
else if (segto == sbss.index)
|
|
s = NULL;
|
|
else {
|
|
error(ERR_WARNING, "attempt to assemble code in"
|
|
" segment %d: defaulting to `.text'", segto);
|
|
s = &stext;
|
|
}
|
|
|
|
if (!s && type != OUT_RESERVE) {
|
|
error(ERR_WARNING, "attempt to initialise memory in the"
|
|
" BSS section: ignored");
|
|
if (type == OUT_REL2ADR)
|
|
realbytes = 2;
|
|
else if (type == OUT_REL4ADR)
|
|
realbytes = 4;
|
|
sbss.len += realbytes;
|
|
return;
|
|
}
|
|
|
|
if (type == OUT_RESERVE) {
|
|
if (s) {
|
|
error(ERR_WARNING, "uninitialised space declared in"
|
|
" %s section: zeroing",
|
|
(segto == stext.index ? "code" : "data"));
|
|
aout_sect_write (s, NULL, realbytes);
|
|
} else
|
|
sbss.len += realbytes;
|
|
} else if (type == OUT_RAWDATA) {
|
|
if (segment != NO_SEG)
|
|
error(ERR_PANIC, "OUT_RAWDATA with other than NO_SEG");
|
|
aout_sect_write (s, data, realbytes);
|
|
} else if (type == OUT_ADDRESS) {
|
|
addr = *(long *)data;
|
|
if (segment != NO_SEG) {
|
|
if (segment % 2) {
|
|
error(ERR_NONFATAL, "a.out format does not support"
|
|
" segment base references");
|
|
} else {
|
|
if (wrt == NO_SEG) {
|
|
aout_add_reloc (s, segment, RELTYPE_ABSOLUTE, realbytes);
|
|
} else if (!bsd) {
|
|
error (ERR_NONFATAL, "Linux a.out format does not support"
|
|
" any use of WRT");
|
|
wrt = NO_SEG; /* we can at least _try_ to continue */
|
|
} else if (wrt == aout_gotpc_sect+1) {
|
|
is_pic = 0x40;
|
|
aout_add_reloc (s, segment, RELTYPE_GOTPC, realbytes);
|
|
} else if (wrt == aout_gotoff_sect+1) {
|
|
is_pic = 0x40;
|
|
addr = aout_add_gotoff_reloc (s, segment,
|
|
addr, realbytes);
|
|
} else if (wrt == aout_got_sect+1) {
|
|
is_pic = 0x40;
|
|
addr = aout_add_gsym_reloc (s, segment, addr, RELTYPE_GOT,
|
|
realbytes, TRUE);
|
|
} else if (wrt == aout_sym_sect+1) {
|
|
addr = aout_add_gsym_reloc (s, segment, addr,
|
|
RELTYPE_ABSOLUTE, realbytes,
|
|
FALSE);
|
|
} else if (wrt == aout_plt_sect+1) {
|
|
is_pic = 0x40;
|
|
error(ERR_NONFATAL, "a.out format cannot produce non-PC-"
|
|
"relative PLT references");
|
|
} else {
|
|
error (ERR_NONFATAL, "a.out format does not support this"
|
|
" use of WRT");
|
|
wrt = NO_SEG; /* we can at least _try_ to continue */
|
|
}
|
|
}
|
|
}
|
|
p = mydata;
|
|
if (realbytes == 2)
|
|
WRITESHORT (p, addr);
|
|
else
|
|
WRITELONG (p, addr);
|
|
aout_sect_write (s, mydata, realbytes);
|
|
} else if (type == OUT_REL2ADR) {
|
|
if (segment == segto)
|
|
error(ERR_PANIC, "intra-segment OUT_REL2ADR");
|
|
if (segment != NO_SEG && segment % 2) {
|
|
error(ERR_NONFATAL, "a.out format does not support"
|
|
" segment base references");
|
|
} else {
|
|
if (wrt == NO_SEG) {
|
|
aout_add_reloc (s, segment, RELTYPE_RELATIVE, 2);
|
|
} else if (!bsd) {
|
|
error (ERR_NONFATAL, "Linux a.out format does not support"
|
|
" any use of WRT");
|
|
wrt = NO_SEG; /* we can at least _try_ to continue */
|
|
} else if (wrt == aout_plt_sect+1) {
|
|
is_pic = 0x40;
|
|
aout_add_reloc (s, segment, RELTYPE_PLT, 2);
|
|
} else if (wrt == aout_gotpc_sect+1 ||
|
|
wrt == aout_gotoff_sect+1 ||
|
|
wrt == aout_got_sect+1) {
|
|
error(ERR_NONFATAL, "a.out format cannot produce PC-"
|
|
"relative GOT references");
|
|
} else {
|
|
error (ERR_NONFATAL, "a.out format does not support this"
|
|
" use of WRT");
|
|
wrt = NO_SEG; /* we can at least _try_ to continue */
|
|
}
|
|
}
|
|
p = mydata;
|
|
WRITESHORT (p, *(long*)data-(realbytes + s->len));
|
|
aout_sect_write (s, mydata, 2L);
|
|
} else if (type == OUT_REL4ADR) {
|
|
if (segment == segto)
|
|
error(ERR_PANIC, "intra-segment OUT_REL4ADR");
|
|
if (segment != NO_SEG && segment % 2) {
|
|
error(ERR_NONFATAL, "a.out format does not support"
|
|
" segment base references");
|
|
} else {
|
|
if (wrt == NO_SEG) {
|
|
aout_add_reloc (s, segment, RELTYPE_RELATIVE, 4);
|
|
} else if (!bsd) {
|
|
error (ERR_NONFATAL, "Linux a.out format does not support"
|
|
" any use of WRT");
|
|
wrt = NO_SEG; /* we can at least _try_ to continue */
|
|
} else if (wrt == aout_plt_sect+1) {
|
|
is_pic = 0x40;
|
|
aout_add_reloc (s, segment, RELTYPE_PLT, 4);
|
|
} else if (wrt == aout_gotpc_sect+1 ||
|
|
wrt == aout_gotoff_sect+1 ||
|
|
wrt == aout_got_sect+1) {
|
|
error(ERR_NONFATAL, "a.out format cannot produce PC-"
|
|
"relative GOT references");
|
|
} else {
|
|
error (ERR_NONFATAL, "a.out format does not support this"
|
|
" use of WRT");
|
|
wrt = NO_SEG; /* we can at least _try_ to continue */
|
|
}
|
|
}
|
|
p = mydata;
|
|
WRITELONG (p, *(long*)data-(realbytes + s->len));
|
|
aout_sect_write (s, mydata, 4L);
|
|
}
|
|
}
|
|
|
|
static void aout_pad_sections(void)
|
|
{
|
|
static unsigned char pad[] = { 0x90, 0x90, 0x90, 0x90 };
|
|
/*
|
|
* Pad each of the text and data sections with NOPs until their
|
|
* length is a multiple of four. (NOP == 0x90.) Also increase
|
|
* the length of the BSS section similarly.
|
|
*/
|
|
aout_sect_write (&stext, pad, (-(long)stext.len) & 3);
|
|
aout_sect_write (&sdata, pad, (-(long)sdata.len) & 3);
|
|
sbss.len = (sbss.len + 3) & ~3;
|
|
}
|
|
|
|
/*
|
|
* a.out files have the curious property that all references to
|
|
* things in the data or bss sections are done by addresses which
|
|
* are actually relative to the start of the _text_ section, in the
|
|
* _file_. (No relation to what happens after linking. No idea why
|
|
* this should be so. It's very strange.) So we have to go through
|
|
* the relocation table, _after_ the final size of each section is
|
|
* known, and fix up the relocations pointed to.
|
|
*/
|
|
static void aout_fixup_relocs(struct Section *sect)
|
|
{
|
|
struct Reloc *r;
|
|
|
|
saa_rewind (sect->data);
|
|
for (r = sect->head; r; r = r->next) {
|
|
unsigned char *p, *q, blk[4];
|
|
long l;
|
|
|
|
saa_fread (sect->data, r->address, blk, (long)r->bytes);
|
|
p = q = blk;
|
|
l = *p++;
|
|
if (r->bytes > 1) {
|
|
l += ((long)*p++) << 8;
|
|
if (r->bytes == 4) {
|
|
l += ((long)*p++) << 16;
|
|
l += ((long)*p++) << 24;
|
|
}
|
|
}
|
|
if (r->symbol == -SECT_DATA)
|
|
l += stext.len;
|
|
else if (r->symbol == -SECT_BSS)
|
|
l += stext.len + sdata.len;
|
|
if (r->bytes == 4)
|
|
WRITELONG(q, l);
|
|
else if (r->bytes == 2)
|
|
WRITESHORT(q, l);
|
|
else
|
|
*q++ = l & 0xFF;
|
|
saa_fwrite (sect->data, r->address, blk, (long)r->bytes);
|
|
}
|
|
}
|
|
|
|
static void aout_write(void)
|
|
{
|
|
/*
|
|
* Emit the a.out header.
|
|
*/
|
|
/* OMAGIC, M_386 or MID_I386, no flags */
|
|
fwritelong (bsd ? 0x07018600 | is_pic : 0x640107L, aoutfp);
|
|
fwritelong (stext.len, aoutfp);
|
|
fwritelong (sdata.len, aoutfp);
|
|
fwritelong (sbss.len, aoutfp);
|
|
fwritelong (nsyms * 12, aoutfp); /* length of symbol table */
|
|
fwritelong (0L, aoutfp); /* object files have no entry point */
|
|
fwritelong (stext.nrelocs * 8, aoutfp); /* size of text relocs */
|
|
fwritelong (sdata.nrelocs * 8, aoutfp); /* size of data relocs */
|
|
|
|
/*
|
|
* Write out the code section and the data section.
|
|
*/
|
|
saa_fpwrite (stext.data, aoutfp);
|
|
saa_fpwrite (sdata.data, aoutfp);
|
|
|
|
/*
|
|
* Write out the relocations.
|
|
*/
|
|
aout_write_relocs (stext.head);
|
|
aout_write_relocs (sdata.head);
|
|
|
|
/*
|
|
* Write the symbol table.
|
|
*/
|
|
aout_write_syms ();
|
|
|
|
/*
|
|
* And the string table.
|
|
*/
|
|
fwritelong (strslen+4, aoutfp); /* length includes length count */
|
|
saa_fpwrite (strs, aoutfp);
|
|
}
|
|
|
|
static void aout_write_relocs (struct Reloc *r)
|
|
{
|
|
while (r) {
|
|
unsigned long word2;
|
|
|
|
fwritelong (r->address, aoutfp);
|
|
|
|
if (r->symbol >= 0)
|
|
word2 = r->symbol;
|
|
else
|
|
word2 = -r->symbol;
|
|
word2 |= r->reltype << 24;
|
|
word2 |= (r->bytes == 1 ? 0 :
|
|
r->bytes == 2 ? 0x2000000L : 0x4000000L);
|
|
fwritelong (word2, aoutfp);
|
|
|
|
r = r->next;
|
|
}
|
|
}
|
|
|
|
static void aout_write_syms (void)
|
|
{
|
|
unsigned long i;
|
|
|
|
saa_rewind (syms);
|
|
for (i = 0; i < nsyms; i++) {
|
|
struct Symbol *sym = saa_rstruct(syms);
|
|
fwritelong (sym->strpos, aoutfp);
|
|
fwritelong ((long)sym->type & ~SYM_WITH_SIZE, aoutfp);
|
|
/*
|
|
* Fix up the symbol value now we know the final section
|
|
* sizes.
|
|
*/
|
|
if ((sym->type & SECT_MASK) == SECT_DATA)
|
|
sym->value += stext.len;
|
|
if ((sym->type & SECT_MASK) == SECT_BSS)
|
|
sym->value += stext.len + sdata.len;
|
|
fwritelong (sym->value, aoutfp);
|
|
/*
|
|
* Output a size record if necessary.
|
|
*/
|
|
if (sym->type & SYM_WITH_SIZE) {
|
|
fwritelong(sym->strpos, aoutfp);
|
|
fwritelong(0x0DL, aoutfp); /* special value: means size */
|
|
fwritelong(sym->size, aoutfp);
|
|
i++; /* use up another of `nsyms' */
|
|
}
|
|
}
|
|
}
|
|
|
|
static void aout_sect_write (struct Section *sect,
|
|
unsigned char *data, unsigned long len)
|
|
{
|
|
saa_wbytes (sect->data, data, len);
|
|
sect->len += len;
|
|
}
|
|
|
|
static long aout_segbase (long segment)
|
|
{
|
|
return segment;
|
|
}
|
|
|
|
static int aout_directive (char *directive, char *value, int pass)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static void aout_filename (char *inname, char *outname, efunc error)
|
|
{
|
|
standard_extension (inname, outname, ".o", error);
|
|
}
|
|
|
|
static const char *aout_stdmac[] = {
|
|
"%define __SECT__ [section .text]",
|
|
"%macro __NASM_CDecl__ 1",
|
|
"%endmacro",
|
|
NULL
|
|
};
|
|
|
|
static int aout_set_info(enum geninfo type, char **val)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif /* OF_AOUT || OF_AOUTB */
|
|
|
|
#ifdef OF_AOUT
|
|
|
|
struct ofmt of_aout = {
|
|
"Linux a.out object files",
|
|
"aout",
|
|
NULL,
|
|
null_debug_arr,
|
|
&null_debug_form,
|
|
aout_stdmac,
|
|
aout_init,
|
|
aout_set_info,
|
|
aout_out,
|
|
aout_deflabel,
|
|
aout_section_names,
|
|
aout_segbase,
|
|
aout_directive,
|
|
aout_filename,
|
|
aout_cleanup
|
|
};
|
|
|
|
#endif
|
|
|
|
#ifdef OF_AOUTB
|
|
|
|
struct ofmt of_aoutb = {
|
|
"NetBSD/FreeBSD a.out object files",
|
|
"aoutb",
|
|
NULL,
|
|
null_debug_arr,
|
|
&null_debug_form,
|
|
aout_stdmac,
|
|
aoutb_init,
|
|
aout_set_info,
|
|
aout_out,
|
|
aout_deflabel,
|
|
aout_section_names,
|
|
aout_segbase,
|
|
aout_directive,
|
|
aout_filename,
|
|
aout_cleanup
|
|
};
|
|
|
|
#endif
|