binutils-gdb/gas/config/obj-aout.c
2015-01-02 00:53:45 +10:30

343 lines
8.6 KiB
C

/* a.out object file format
Copyright (C) 1989-2015 Free Software Foundation, Inc.
This file is part of GAS, the GNU Assembler.
GAS is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 3,
or (at your option) any later version.
GAS is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
the GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GAS; see the file COPYING. If not, write to the Free
Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
02110-1301, USA. */
#define OBJ_HEADER "obj-aout.h"
#include "as.h"
#undef NO_RELOC
#include "aout/aout64.h"
void
obj_aout_frob_symbol (symbolS *sym, int *punt ATTRIBUTE_UNUSED)
{
flagword flags;
asection *sec;
int type;
flags = symbol_get_bfdsym (sym)->flags;
type = aout_symbol (symbol_get_bfdsym (sym))->type;
sec = S_GET_SEGMENT (sym);
/* Only frob simple symbols this way right now. */
if (! (type & ~ (N_TYPE | N_EXT)))
{
if (type == (N_UNDF | N_EXT)
&& sec == bfd_abs_section_ptr)
{
sec = bfd_und_section_ptr;
S_SET_SEGMENT (sym, sec);
}
if ((type & N_TYPE) != N_INDR
&& (type & N_TYPE) != N_SETA
&& (type & N_TYPE) != N_SETT
&& (type & N_TYPE) != N_SETD
&& (type & N_TYPE) != N_SETB
&& type != N_WARNING
&& (sec == bfd_abs_section_ptr
|| sec == bfd_und_section_ptr))
return;
if (flags & BSF_EXPORT)
type |= N_EXT;
switch (type & N_TYPE)
{
case N_SETA:
case N_SETT:
case N_SETD:
case N_SETB:
/* Set the debugging flag for constructor symbols so that
BFD leaves them alone. */
symbol_get_bfdsym (sym)->flags |= BSF_DEBUGGING;
/* You can't put a common symbol in a set. The way a set
element works is that the symbol has a definition and a
name, and the linker adds the definition to the set of
that name. That does not work for a common symbol,
because the linker can't tell which common symbol the
user means. FIXME: Using as_bad here may be
inappropriate, since the user may want to force a
particular type without regard to the semantics of sets;
on the other hand, we certainly don't want anybody to be
mislead into thinking that their code will work. */
if (S_IS_COMMON (sym))
as_bad (_("Attempt to put a common symbol into set %s"),
S_GET_NAME (sym));
/* Similarly, you can't put an undefined symbol in a set. */
else if (! S_IS_DEFINED (sym))
as_bad (_("Attempt to put an undefined symbol into set %s"),
S_GET_NAME (sym));
break;
case N_INDR:
/* Put indirect symbols in the indirect section. */
S_SET_SEGMENT (sym, bfd_ind_section_ptr);
symbol_get_bfdsym (sym)->flags |= BSF_INDIRECT;
if (type & N_EXT)
{
symbol_get_bfdsym (sym)->flags |= BSF_EXPORT;
symbol_get_bfdsym (sym)->flags &=~ BSF_LOCAL;
}
break;
case N_WARNING:
/* Mark warning symbols. */
symbol_get_bfdsym (sym)->flags |= BSF_WARNING;
break;
}
}
else
symbol_get_bfdsym (sym)->flags |= BSF_DEBUGGING;
aout_symbol (symbol_get_bfdsym (sym))->type = type;
/* Double check weak symbols. */
if (S_IS_WEAK (sym) && S_IS_COMMON (sym))
as_bad (_("Symbol `%s' can not be both weak and common"),
S_GET_NAME (sym));
}
void
obj_aout_frob_file_before_fix (void)
{
/* Relocation processing may require knowing the VMAs of the sections.
Since writing to a section will cause the BFD back end to compute the
VMAs, fake it out here.... */
bfd_byte b = 0;
bfd_boolean x = TRUE;
if (bfd_section_size (stdoutput, text_section) != 0)
x = bfd_set_section_contents (stdoutput, text_section, &b, (file_ptr) 0,
(bfd_size_type) 1);
else if (bfd_section_size (stdoutput, data_section) != 0)
x = bfd_set_section_contents (stdoutput, data_section, &b, (file_ptr) 0,
(bfd_size_type) 1);
gas_assert (x);
}
static void
obj_aout_line (int ignore ATTRIBUTE_UNUSED)
{
/* Assume delimiter is part of expression.
BSD4.2 as fails with delightful bug, so we
are not being incompatible here. */
new_logical_line ((char *) NULL, (int) (get_absolute_expression ()));
demand_empty_rest_of_line ();
}
/* Handle .weak. This is a GNU extension. */
static void
obj_aout_weak (int ignore ATTRIBUTE_UNUSED)
{
char *name;
int c;
symbolS *symbolP;
do
{
name = input_line_pointer;
c = get_symbol_end ();
symbolP = symbol_find_or_make (name);
*input_line_pointer = c;
SKIP_WHITESPACE ();
S_SET_WEAK (symbolP);
if (c == ',')
{
input_line_pointer++;
SKIP_WHITESPACE ();
if (*input_line_pointer == '\n')
c = '\n';
}
}
while (c == ',');
demand_empty_rest_of_line ();
}
/* Handle .type. On {Net,Open}BSD, this is used to set the n_other field,
which is then apparently used when doing dynamic linking. Older
versions of gas ignored the .type pseudo-op, so we also ignore it if
we can't parse it. */
static void
obj_aout_type (int ignore ATTRIBUTE_UNUSED)
{
char *name;
int c;
symbolS *sym;
name = input_line_pointer;
c = get_symbol_end ();
sym = symbol_find_or_make (name);
*input_line_pointer = c;
SKIP_WHITESPACE ();
if (*input_line_pointer == ',')
{
++input_line_pointer;
SKIP_WHITESPACE ();
if (*input_line_pointer == '@')
{
++input_line_pointer;
if (strncmp (input_line_pointer, "object", 6) == 0)
S_SET_OTHER (sym, 1);
else if (strncmp (input_line_pointer, "function", 8) == 0)
S_SET_OTHER (sym, 2);
}
}
/* Ignore everything else on the line. */
s_ignore (0);
}
/* Support for an AOUT emulation. */
static void
aout_pop_insert (void)
{
pop_insert (aout_pseudo_table);
}
static int
obj_aout_s_get_other (symbolS *sym)
{
return aout_symbol (symbol_get_bfdsym (sym))->other;
}
static void
obj_aout_s_set_other (symbolS *sym, int o)
{
aout_symbol (symbol_get_bfdsym (sym))->other = o;
}
static int
obj_aout_sec_sym_ok_for_reloc (asection *sec ATTRIBUTE_UNUSED)
{
return obj_sec_sym_ok_for_reloc (sec);
}
static void
obj_aout_process_stab (segT seg ATTRIBUTE_UNUSED,
int w,
const char *s,
int t,
int o,
int d)
{
aout_process_stab (w, s, t, o, d);
}
static int
obj_aout_s_get_desc (symbolS *sym)
{
return aout_symbol (symbol_get_bfdsym (sym))->desc;
}
static void
obj_aout_s_set_desc (symbolS *sym, int d)
{
aout_symbol (symbol_get_bfdsym (sym))->desc = d;
}
static int
obj_aout_s_get_type (symbolS *sym)
{
return aout_symbol (symbol_get_bfdsym (sym))->type;
}
static void
obj_aout_s_set_type (symbolS *sym, int t)
{
aout_symbol (symbol_get_bfdsym (sym))->type = t;
}
static int
obj_aout_separate_stab_sections (void)
{
return 0;
}
/* When changed, make sure these table entries match the single-format
definitions in obj-aout.h. */
const struct format_ops aout_format_ops =
{
bfd_target_aout_flavour,
1, /* dfl_leading_underscore. */
0, /* emit_section_symbols. */
0, /* begin. */
0, /* app_file. */
obj_aout_frob_symbol,
0, /* frob_file. */
0, /* frob_file_before_adjust. */
obj_aout_frob_file_before_fix,
0, /* frob_file_after_relocs. */
0, /* s_get_size. */
0, /* s_set_size. */
0, /* s_get_align. */
0, /* s_set_align. */
obj_aout_s_get_other,
obj_aout_s_set_other,
obj_aout_s_get_desc,
obj_aout_s_set_desc,
obj_aout_s_get_type,
obj_aout_s_set_type,
0, /* copy_symbol_attributes. */
0, /* generate_asm_lineno. */
obj_aout_process_stab,
obj_aout_separate_stab_sections,
0, /* init_stab_section. */
obj_aout_sec_sym_ok_for_reloc,
aout_pop_insert,
0, /* ecoff_set_ext. */
0, /* read_begin_hook. */
0, /* symbol_new_hook. */
0, /* symbol_clone_hook. */
0 /* adjust_symtab. */
};
const pseudo_typeS aout_pseudo_table[] =
{
{"line", obj_aout_line, 0}, /* Source code line number. */
{"ln", obj_aout_line, 0}, /* COFF line number that we use anyway. */
{"weak", obj_aout_weak, 0}, /* Mark symbol as weak. */
{"type", obj_aout_type, 0},
/* coff debug pseudos (ignored) */
{"def", s_ignore, 0},
{"dim", s_ignore, 0},
{"endef", s_ignore, 0},
{"ident", s_ignore, 0},
{"line", s_ignore, 0},
{"ln", s_ignore, 0},
{"scl", s_ignore, 0},
{"size", s_ignore, 0},
{"tag", s_ignore, 0},
{"val", s_ignore, 0},
{"version", s_ignore, 0},
{"optim", s_ignore, 0}, /* For sun386i cc (?). */
/* other stuff */
{"ABORT", s_abort, 0},
{NULL, NULL, 0}
};