binutils-gdb/gas/as.c
Indu Bhagat c7defc5386 gas: x86: synthesize CFI for hand-written asm
This patch adds support in GAS to create generic GAS instructions
(a.k.a., the ginsn) for the x86 backend (AMD64 ABI only at this time).
Using this ginsn infrastructure, GAS can then synthesize CFI for
hand-written asm for x86_64.

A ginsn is a target-independent representation of the machine
instructions.  One machine instruction may need one or more ginsn.

This patch also adds skeleton support for printing ginsn in the listing
output for debugging purposes.

Since the current use-case of ginsn is to synthesize CFI, the x86 target
needs to generate ginsns necessary for the following machine
instructions only:

 - All change of flow instructions, including all conditional and
   unconditional branches, call and return from functions.
 - All register saves and unsaves to the stack.
 - All instructions affecting the two registers that could potentially
   be used as the base register for CFA tracking.  For SCFI, the base
   register for CFA tracking is limited to REG_SP and REG_FP only for
   now.

The representation of ginsn is kept simple:

- GAS instruction has GINSN_NUM_SRC_OPNDS (defined to be 2 at this time)
  number of source operands and one destination operand at this time.
- GAS instruction uses DWARF register numbers in its representation and
  does not track register size.
- GAS instructions carry location information (file name and line
  number).
- GAS instructions are ID's with a natural number in order of their
  addtion to the list.  This can be used as a proxy for the static
  program order of the corresponding machine instructions.

Note that, GAS instruction (ginsn) format does not support
GINSN_TYPE_PUSH and GINSN_TYPE_POP.  Some architectures, like aarch64,
do not have push and pop instructions, but rather STP/LDP/STR/LDR etc.
instructions.  Further these instructions have a variety of addressing
modes, like offset, pre-indexing and post-indexing etc.  Among other
things, one of differences in these addressing modes is _when_ the addr
register is updated with the result of the address calculation: before
or after the memory operation.  To best support such needs, the generic
instructions like GINSN_TYPE_LOAD, GINSN_TYPE_STORE together with
GINSN_TYPE_ADD, and GINSN_TYPE_SUB may be used.

The functionality provided in ginsn.c and scfi.c is compiled in when a
target defines TARGET_USE_SCFI and TARGET_USE_GINSN.  This can be
revisited later when there are other use-cases of creating ginsn's in
GAS, apart from the current use-case of synthesizing CFI for
hand-written asm.

Support is added only for System V AMD64 ABI for ELF at this time.  If
the user enables SCFI with --32, GAS issues an error:

  "Fatal error: SCFI is not supported for this ABI"

For synthesizing (DWARF) CFI, the SCFI machinery requires the programmer
to adhere to some pre-requisites for their asm:
   - Hand-written asm block must begin with a .type   foo, @function
It is highly recommended to, additionally, also ensure that:
   - Hand-written asm block ends with a .size foo, .-foo

The SCFI machinery encodes some rules which align with the standard
calling convention specified by the ABI.  Apart from the rules, the SCFI
machinery employs some heuristics.  For example:
   - The base register for CFA tracking may be either REG_SP or REG_FP.
   - If the base register for CFA tracking is REG_SP, the precise amount of
     stack usage (and hence, the value of REG_SP) must be known at all times.
   - If using dynamic stack allocation, the function must switch to
     FP-based CFA.  This means using instructions like the following (in
     AMD64) in prologue:
        pushq   %rbp
        movq    %rsp, %rbp
     and analogous instructions in epilogue.
   - Save and Restore of callee-saved registers must be symmetrical.
     However, the SCFI machinery at this time only warns if any such
     asymmetry is seen.

These heuristics/rules are architecture-independent and are meant to
employed for all architectures/ABIs using SCFI in the future.

gas/
	* Makefile.am: Add new files.
	* Makefile.in: Regenerated.
	* as.c (defined): Handle documentation and listing option for
	ginsns and SCFI.
	* config/obj-elf.c (obj_elf_size): Invoke ginsn_data_end.
	(obj_elf_type): Invoke ginsn_data_begin.
	* config/tc-i386.c (x86_scfi_callee_saved_p): New function.
	(ginsn_prefix_66H_p): Likewise.
	(ginsn_dw2_regnum): Likewise.
	(x86_ginsn_addsub_reg_mem): Likewise.
	(x86_ginsn_addsub_mem_reg): Likewise.
	(x86_ginsn_alu_imm): Likewise.
	(x86_ginsn_move): Likewise.
	(x86_ginsn_lea): Likewise.
	(x86_ginsn_jump): Likewise.
	(x86_ginsn_jump_cond): Likewise.
	(x86_ginsn_enter): Likewise.
	(x86_ginsn_safe_to_skip): Likewise.
	(x86_ginsn_unhandled): Likewise.
	(x86_ginsn_new): New functionality to generate ginsns.
	(md_assemble): Invoke x86_ginsn_new.
	(s_insn): Likewise.
	(i386_target_format): Add hard error for usage of SCFI with non AMD64 ABIs.
	* config/tc-i386.h (TARGET_USE_GINSN): New definition.
	(TARGET_USE_SCFI): Likewise.
	(SCFI_MAX_REG_ID): Likewise.
	(REG_FP): Likewise.
	(REG_SP): Likewise.
	(SCFI_INIT_CFA_OFFSET): Likewise.
	(SCFI_CALLEE_SAVED_REG_P): Likewise.
	(x86_scfi_callee_saved_p): Likewise.
	* gas/listing.h (LISTING_GINSN_SCFI): New define for ginsn and
	SCFI.
	* gas/read.c (read_a_source_file): Close SCFI processing at end
	of file read.
	* gas/scfidw2gen.c (scfi_process_cfi_label): Add implementation.
	(scfi_process_cfi_signal_frame): Likewise.
	* subsegs.h (struct frch_ginsn_data): New forward declaration.
	(struct frchain): New member for ginsn data.
	* gas/subsegs.c (subseg_set_rest): Initialize the new member.
	* symbols.c (colon): Invoke ginsn_frob_label to convey
	user-defined labels to ginsn infrastructure.
	* ginsn.c: New file.
	* ginsn.h: New file.
	* scfi.c: New file.
	* scfi.h: New file.
2024-01-15 03:31:35 -08:00

1523 lines
43 KiB
C
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/* as.c - GAS main program.
Copyright (C) 1987-2024 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. */
/* Main program for AS; a 32-bit assembler of GNU.
Understands command arguments.
Has a few routines that don't fit in other modules because they
are shared.
bugs
: initialisers
Since no-one else says they will support them in future: I
don't support them now. */
#define COMMON
/* Disable code to set FAKE_LABEL_NAME in obj-multi.h, to avoid circular
reference. */
#define INITIALIZING_EMULS
#include "as.h"
#include "subsegs.h"
#include "output-file.h"
#include "sb.h"
#include "macro.h"
#include "dwarf2dbg.h"
#include "dw2gencfi.h"
#include "codeview.h"
#include "bfdver.h"
#include "write.h"
#include "ginsn.h"
#ifdef HAVE_ITBL_CPU
#include "itbl-ops.h"
#else
#define itbl_init()
#endif
#ifdef USING_CGEN
/* Perform any cgen specific initialisation for gas. */
extern void gas_cgen_begin (void);
#endif
/* We build a list of defsyms as we read the options, and then define
them after we have initialized everything. */
struct defsym_list
{
struct defsym_list *next;
char *name;
valueT value;
};
/* True if a listing is wanted. */
int listing;
/* Type of debugging to generate. */
enum debug_info_type debug_type = DEBUG_UNSPECIFIED;
int use_gnu_debug_info_extensions = 0;
#ifndef MD_DEBUG_FORMAT_SELECTOR
#define MD_DEBUG_FORMAT_SELECTOR NULL
#endif
static enum debug_info_type (*md_debug_format_selector) (int *) = MD_DEBUG_FORMAT_SELECTOR;
/* Maximum level of macro nesting. */
int max_macro_nest = 100;
/* argv[0] */
static char * myname;
/* The default obstack chunk size. If we set this to zero, the
obstack code will use whatever will fit in a 4096 byte block. */
int chunksize = 0;
/* To monitor memory allocation more effectively, make this non-zero.
Then the chunk sizes for gas and bfd will be reduced. */
int debug_memory = 0;
/* Enable verbose mode. */
int verbose = 0;
/* Which version of DWARF CIE to produce. This default value of -1
indicates that this value has not been set yet, a default value is
provided in dwarf2_init. A different value can also be supplied by the
command line flag --gdwarf-cie-version, or by a target in
MD_AFTER_PARSE_ARGS. */
int flag_dwarf_cie_version = -1;
/* The maximum level of DWARF DEBUG information we should manufacture.
This defaults to 3 unless overridden by a command line option. */
unsigned int dwarf_level = 3;
#if defined OBJ_ELF || defined OBJ_MAYBE_ELF
int flag_use_elf_stt_common = DEFAULT_GENERATE_ELF_STT_COMMON;
bool flag_generate_build_notes = DEFAULT_GENERATE_BUILD_NOTES;
#endif
segT reg_section;
segT expr_section;
segT text_section;
segT data_section;
segT bss_section;
/* Name of listing file. */
static char *listing_filename = NULL;
static struct defsym_list *defsyms;
static long start_time;
#ifdef USE_EMULATIONS
#define EMULATION_ENVIRON "AS_EMULATION"
extern struct emulation mipsbelf, mipslelf, mipself;
extern struct emulation i386coff, i386elf, i386aout;
extern struct emulation crisaout, criself;
static struct emulation *const emulations[] = { EMULATIONS };
static const int n_emulations = sizeof (emulations) / sizeof (emulations[0]);
static void
select_emulation_mode (int argc, char **argv)
{
int i;
char *p;
const char *em = NULL;
for (i = 1; i < argc; i++)
if (startswith (argv[i], "--em"))
break;
if (i == argc)
goto do_default;
p = strchr (argv[i], '=');
if (p)
p++;
else
p = argv[i + 1];
if (!p || !*p)
as_fatal (_("missing emulation mode name"));
em = p;
do_default:
if (em == 0)
em = getenv (EMULATION_ENVIRON);
if (em == 0)
em = DEFAULT_EMULATION;
if (em)
{
for (i = 0; i < n_emulations; i++)
if (!strcmp (emulations[i]->name, em))
break;
if (i == n_emulations)
as_fatal (_("unrecognized emulation name `%s'"), em);
this_emulation = emulations[i];
}
else
this_emulation = emulations[0];
this_emulation->init ();
}
const char *
default_emul_bfd_name (void)
{
abort ();
return NULL;
}
void
common_emul_init (void)
{
this_format = this_emulation->format;
if (this_emulation->leading_underscore == 2)
this_emulation->leading_underscore = this_format->dfl_leading_underscore;
if (this_emulation->default_endian != 2)
target_big_endian = this_emulation->default_endian;
if (this_emulation->fake_label_name == 0)
{
if (this_emulation->leading_underscore)
this_emulation->fake_label_name = FAKE_LABEL_NAME;
else
/* What other parameters should we test? */
this_emulation->fake_label_name = "." FAKE_LABEL_NAME;
}
}
#endif
void
print_version_id (void)
{
static int printed;
if (printed)
return;
printed = 1;
fprintf (stderr, _("GNU assembler version %s (%s) using BFD version %s\n"),
VERSION, TARGET_ALIAS, BFD_VERSION_STRING);
}
#ifdef DEFAULT_FLAG_COMPRESS_DEBUG
enum compressed_debug_section_type flag_compress_debug
= DEFAULT_COMPRESSED_DEBUG_ALGORITHM;
#define DEFAULT_COMPRESSED_DEBUG_ALGORITHM_HELP \
DEFAULT_COMPRESSED_DEBUG_ALGORITHM
#else
#define DEFAULT_COMPRESSED_DEBUG_ALGORITHM_HELP COMPRESS_DEBUG_NONE
#endif
static void
show_usage (FILE * stream)
{
fprintf (stream, _("Usage: %s [option...] [asmfile...]\n"), myname);
fprintf (stream, _("\
Options:\n\
-a[sub-option...] turn on listings\n\
Sub-options [default hls]:\n\
c omit false conditionals\n\
d omit debugging directives\n\
g include general info\n\
h include high-level source\n\
i include ginsn and synthesized CFI info\n\
l include assembly\n\
m include macro expansions\n\
n omit forms processing\n\
s include symbols\n\
=FILE list to FILE (must be last sub-option)\n"));
fprintf (stream, _("\
--alternate initially turn on alternate macro syntax\n"));
fprintf (stream, _("\
--compress-debug-sections[={none|zlib|zlib-gnu|zlib-gabi|zstd}]\n\
compress DWARF debug sections\n")),
fprintf (stream, _("\
Default: %s\n"),
bfd_get_compression_algorithm_name
(DEFAULT_COMPRESSED_DEBUG_ALGORITHM_HELP));
fprintf (stream, _("\
--nocompress-debug-sections\n\
don't compress DWARF debug sections\n"));
fprintf (stream, _("\
-D produce assembler debugging messages\n"));
fprintf (stream, _("\
--dump-config display how the assembler is configured and then exit\n"));
fprintf (stream, _("\
--debug-prefix-map OLD=NEW\n\
map OLD to NEW in debug information\n"));
fprintf (stream, _("\
--defsym SYM=VAL define symbol SYM to given value\n"));
#ifdef USE_EMULATIONS
{
int i;
const char *def_em;
fprintf (stream, "\
--emulation=[");
for (i = 0; i < n_emulations - 1; i++)
fprintf (stream, "%s | ", emulations[i]->name);
fprintf (stream, "%s]\n", emulations[i]->name);
def_em = getenv (EMULATION_ENVIRON);
if (!def_em)
def_em = DEFAULT_EMULATION;
fprintf (stream, _("\
emulate output (default %s)\n"), def_em);
}
#endif
#if defined OBJ_ELF || defined OBJ_MAYBE_ELF
fprintf (stream, _("\
--execstack require executable stack for this object\n"));
fprintf (stream, _("\
--noexecstack don't require executable stack for this object\n"));
fprintf (stream, _("\
--size-check=[error|warning]\n\
ELF .size directive check (default --size-check=error)\n"));
fprintf (stream, _("\
--elf-stt-common=[no|yes] "));
if (DEFAULT_GENERATE_ELF_STT_COMMON)
fprintf (stream, _("(default: yes)\n"));
else
fprintf (stream, _("(default: no)\n"));
fprintf (stream, _("\
generate ELF common symbols with STT_COMMON type\n"));
fprintf (stream, _("\
--sectname-subst enable section name substitution sequences\n"));
fprintf (stream, _("\
--generate-missing-build-notes=[no|yes] "));
#if DEFAULT_GENERATE_BUILD_NOTES
fprintf (stream, _("(default: yes)\n"));
#else
fprintf (stream, _("(default: no)\n"));
#endif
fprintf (stream, _("\
generate GNU Build notes if none are present in the input\n"));
fprintf (stream, _("\
--gsframe generate SFrame stack trace information\n"));
# if defined (TARGET_USE_SCFI) && defined (TARGET_USE_GINSN)
fprintf (stream, _("\
--scfi=experimental Synthesize DWARF CFI for hand-written asm\n\
(experimental support)\n"));
# endif
#endif /* OBJ_ELF */
fprintf (stream, _("\
-f skip whitespace and comment preprocessing\n"));
fprintf (stream, _("\
-g --gen-debug generate debugging information\n"));
fprintf (stream, _("\
--gstabs generate STABS debugging information\n"));
fprintf (stream, _("\
--gstabs+ generate STABS debug info with GNU extensions\n"));
fprintf (stream, _("\
--gdwarf-<N> generate DWARF<N> debugging information. 2 <= <N> <= 5\n"));
fprintf (stream, _("\
--gdwarf-cie-version=<N> generate version 1, 3 or 4 DWARF CIEs\n"));
fprintf (stream, _("\
--gdwarf-sections generate per-function section names for DWARF line information\n"));
#if defined (TE_PE) && defined (O_secrel)
fprintf (stream, _("\
--gcodeview generate CodeView debugging information\n"));
#endif
fprintf (stream, _("\
--hash-size=<N> ignored\n"));
fprintf (stream, _("\
--help show all assembler options\n"));
fprintf (stream, _("\
--target-help show target specific options\n"));
fprintf (stream, _("\
-I DIR add DIR to search list for .include directives\n"));
fprintf (stream, _("\
-J don't warn about signed overflow\n"));
fprintf (stream, _("\
-K warn when differences altered for long displacements\n"));
fprintf (stream, _("\
-L,--keep-locals keep local symbols (e.g. starting with `L')\n"));
fprintf (stream, _("\
-M,--mri assemble in MRI compatibility mode\n"));
fprintf (stream, _("\
--MD FILE write dependency information in FILE (default none)\n"));
fprintf (stream, _("\
--multibyte-handling=<method>\n\
what to do with multibyte characters encountered in the input\n"));
fprintf (stream, _("\
-nocpp ignored\n"));
fprintf (stream, _("\
-no-pad-sections do not pad the end of sections to alignment boundaries\n"));
fprintf (stream, _("\
-o OBJFILE name the object-file output OBJFILE (default a.out)\n"));
fprintf (stream, _("\
-R fold data section into text section\n"));
fprintf (stream, _("\
--reduce-memory-overheads ignored\n"));
fprintf (stream, _("\
--statistics print various measured statistics from execution\n"));
fprintf (stream, _("\
--strip-local-absolute strip local absolute symbols\n"));
fprintf (stream, _("\
--traditional-format Use same format as native assembler when possible\n"));
fprintf (stream, _("\
--version print assembler version number and exit\n"));
fprintf (stream, _("\
-W --no-warn suppress warnings\n"));
fprintf (stream, _("\
--warn don't suppress warnings\n"));
fprintf (stream, _("\
--fatal-warnings treat warnings as errors\n"));
#ifdef HAVE_ITBL_CPU
fprintf (stream, _("\
--itbl INSTTBL extend instruction set to include instructions\n\
matching the specifications defined in file INSTTBL\n"));
#endif
fprintf (stream, _("\
-w ignored\n"));
fprintf (stream, _("\
-X ignored\n"));
fprintf (stream, _("\
-Z generate object file even after errors\n"));
fprintf (stream, _("\
--listing-lhs-width set the width in words of the output data column of\n\
the listing\n"));
fprintf (stream, _("\
--listing-lhs-width2 set the width in words of the continuation lines\n\
of the output data column; ignored if smaller than\n\
the width of the first line\n"));
fprintf (stream, _("\
--listing-rhs-width set the max width in characters of the lines from\n\
the source file\n"));
fprintf (stream, _("\
--listing-cont-lines set the maximum number of continuation lines used\n\
for the output data column of the listing\n"));
fprintf (stream, _("\
@FILE read options from FILE\n"));
md_show_usage (stream);
fputc ('\n', stream);
if (REPORT_BUGS_TO[0] && stream == stdout)
fprintf (stream, _("Report bugs to %s\n"), REPORT_BUGS_TO);
}
/* Since it is easy to do here we interpret the special arg "-"
to mean "use stdin" and we set that argv[] pointing to "".
After we have munged argv[], the only things left are source file
name(s) and ""(s) denoting stdin. These file names are used
(perhaps more than once) later.
check for new machine-dep cmdline options in
md_parse_option definitions in config/tc-*.c. */
static void
parse_args (int * pargc, char *** pargv)
{
int old_argc;
int new_argc;
char ** old_argv;
char ** new_argv;
/* Starting the short option string with '-' is for programs that
expect options and other ARGV-elements in any order and that care about
the ordering of the two. We describe each non-option ARGV-element
as if it were the argument of an option with character code 1. */
char *shortopts;
extern const char *md_shortopts;
static const char std_shortopts[] =
{
'-', 'J',
#ifndef WORKING_DOT_WORD
/* -K is not meaningful if .word is not being hacked. */
'K',
#endif
'L', 'M', 'R', 'W', 'Z', 'a', ':', ':', 'D', 'f', 'g', ':',':', 'I', ':', 'o', ':',
#ifndef VMS
/* -v takes an argument on VMS, so we don't make it a generic
option. */
'v',
#endif
'w', 'X',
#ifdef HAVE_ITBL_CPU
/* New option for extending instruction set (see also --itbl below). */
't', ':',
#endif
'\0'
};
struct option *longopts;
extern struct option md_longopts[];
extern size_t md_longopts_size;
/* Codes used for the long options with no short synonyms. */
enum option_values
{
OPTION_HELP = OPTION_STD_BASE,
OPTION_NOCPP,
OPTION_STATISTICS,
OPTION_VERSION,
OPTION_DUMPCONFIG,
OPTION_VERBOSE,
OPTION_EMULATION,
OPTION_DEBUG_PREFIX_MAP,
OPTION_DEFSYM,
OPTION_LISTING_LHS_WIDTH,
OPTION_LISTING_LHS_WIDTH2, /* = STD_BASE + 10 */
OPTION_LISTING_RHS_WIDTH,
OPTION_LISTING_CONT_LINES,
OPTION_DEPFILE,
OPTION_GSTABS,
OPTION_GSTABS_PLUS,
OPTION_GDWARF_2,
OPTION_GDWARF_3,
OPTION_GDWARF_4,
OPTION_GDWARF_5,
OPTION_GDWARF_SECTIONS, /* = STD_BASE + 20 */
OPTION_GDWARF_CIE_VERSION,
OPTION_GCODEVIEW,
OPTION_STRIP_LOCAL_ABSOLUTE,
OPTION_TRADITIONAL_FORMAT,
OPTION_WARN,
OPTION_TARGET_HELP,
OPTION_EXECSTACK,
OPTION_NOEXECSTACK,
OPTION_SIZE_CHECK,
OPTION_ELF_STT_COMMON,
OPTION_ELF_BUILD_NOTES, /* = STD_BASE + 30 */
OPTION_SECTNAME_SUBST,
OPTION_ALTERNATE,
OPTION_AL,
OPTION_HASH_TABLE_SIZE,
OPTION_REDUCE_MEMORY_OVERHEADS,
OPTION_WARN_FATAL,
OPTION_COMPRESS_DEBUG,
OPTION_NOCOMPRESS_DEBUG,
OPTION_NO_PAD_SECTIONS,
OPTION_MULTIBYTE_HANDLING, /* = STD_BASE + 40 */
OPTION_SFRAME,
OPTION_SCFI
/* When you add options here, check that they do
not collide with OPTION_MD_BASE. See as.h. */
};
static const struct option std_longopts[] =
{
/* Note: commas are placed at the start of the line rather than
the end of the preceding line so that it is simpler to
selectively add and remove lines from this list. */
{"alternate", no_argument, NULL, OPTION_ALTERNATE}
/* The entry for "a" is here to prevent getopt_long_only() from
considering that -a is an abbreviation for --alternate. This is
necessary because -a=<FILE> is a valid switch but getopt would
normally reject it since --alternate does not take an argument. */
,{"a", optional_argument, NULL, 'a'}
/* Handle -al=<FILE>. */
,{"al", optional_argument, NULL, OPTION_AL}
,{"compress-debug-sections", optional_argument, NULL, OPTION_COMPRESS_DEBUG}
,{"nocompress-debug-sections", no_argument, NULL, OPTION_NOCOMPRESS_DEBUG}
,{"debug-prefix-map", required_argument, NULL, OPTION_DEBUG_PREFIX_MAP}
,{"defsym", required_argument, NULL, OPTION_DEFSYM}
,{"dump-config", no_argument, NULL, OPTION_DUMPCONFIG}
,{"emulation", required_argument, NULL, OPTION_EMULATION}
#if defined OBJ_ELF || defined OBJ_MAYBE_ELF
,{"execstack", no_argument, NULL, OPTION_EXECSTACK}
,{"noexecstack", no_argument, NULL, OPTION_NOEXECSTACK}
,{"size-check", required_argument, NULL, OPTION_SIZE_CHECK}
,{"elf-stt-common", required_argument, NULL, OPTION_ELF_STT_COMMON}
,{"sectname-subst", no_argument, NULL, OPTION_SECTNAME_SUBST}
,{"generate-missing-build-notes", required_argument, NULL, OPTION_ELF_BUILD_NOTES}
,{"gsframe", no_argument, NULL, OPTION_SFRAME}
# if defined (TARGET_USE_SCFI) && defined (TARGET_USE_GINSN)
,{"scfi", required_argument, NULL, OPTION_SCFI}
# endif
#endif /* OBJ_ELF || OBJ_MAYBE_ELF. */
,{"fatal-warnings", no_argument, NULL, OPTION_WARN_FATAL}
,{"gdwarf-2", no_argument, NULL, OPTION_GDWARF_2}
,{"gdwarf-3", no_argument, NULL, OPTION_GDWARF_3}
,{"gdwarf-4", no_argument, NULL, OPTION_GDWARF_4}
,{"gdwarf-5", no_argument, NULL, OPTION_GDWARF_5}
/* GCC uses --gdwarf-2 but GAS used to to use --gdwarf2,
so we keep it here for backwards compatibility. */
,{"gdwarf2", no_argument, NULL, OPTION_GDWARF_2}
,{"gdwarf-sections", no_argument, NULL, OPTION_GDWARF_SECTIONS}
,{"gdwarf-cie-version", required_argument, NULL, OPTION_GDWARF_CIE_VERSION}
#if defined (TE_PE) && defined (O_secrel)
,{"gcodeview", no_argument, NULL, OPTION_GCODEVIEW}
#endif
,{"gen-debug", no_argument, NULL, 'g'}
,{"gstabs", no_argument, NULL, OPTION_GSTABS}
,{"gstabs+", no_argument, NULL, OPTION_GSTABS_PLUS}
,{"hash-size", required_argument, NULL, OPTION_HASH_TABLE_SIZE}
,{"help", no_argument, NULL, OPTION_HELP}
#ifdef HAVE_ITBL_CPU
/* New option for extending instruction set (see also -t above).
The "-t file" or "--itbl file" option extends the basic set of
valid instructions by reading "file", a text file containing a
list of instruction formats. The additional opcodes and their
formats are added to the built-in set of instructions, and
mnemonics for new registers may also be defined. */
,{"itbl", required_argument, NULL, 't'}
#endif
/* getopt allows abbreviations, so we do this to stop it from
treating -k as an abbreviation for --keep-locals. Some
ports use -k to enable PIC assembly. */
,{"keep-locals", no_argument, NULL, 'L'}
,{"keep-locals", no_argument, NULL, 'L'}
,{"listing-lhs-width", required_argument, NULL, OPTION_LISTING_LHS_WIDTH}
,{"listing-lhs-width2", required_argument, NULL, OPTION_LISTING_LHS_WIDTH2}
,{"listing-rhs-width", required_argument, NULL, OPTION_LISTING_RHS_WIDTH}
,{"listing-cont-lines", required_argument, NULL, OPTION_LISTING_CONT_LINES}
,{"MD", required_argument, NULL, OPTION_DEPFILE}
,{"mri", no_argument, NULL, 'M'}
,{"nocpp", no_argument, NULL, OPTION_NOCPP}
,{"no-pad-sections", no_argument, NULL, OPTION_NO_PAD_SECTIONS}
,{"no-warn", no_argument, NULL, 'W'}
,{"reduce-memory-overheads", no_argument, NULL, OPTION_REDUCE_MEMORY_OVERHEADS}
,{"statistics", no_argument, NULL, OPTION_STATISTICS}
,{"strip-local-absolute", no_argument, NULL, OPTION_STRIP_LOCAL_ABSOLUTE}
,{"version", no_argument, NULL, OPTION_VERSION}
,{"verbose", no_argument, NULL, OPTION_VERBOSE}
,{"target-help", no_argument, NULL, OPTION_TARGET_HELP}
,{"traditional-format", no_argument, NULL, OPTION_TRADITIONAL_FORMAT}
,{"warn", no_argument, NULL, OPTION_WARN}
,{"multibyte-handling", required_argument, NULL, OPTION_MULTIBYTE_HANDLING}
};
/* Construct the option lists from the standard list and the target
dependent list. Include space for an extra NULL option and
always NULL terminate. */
shortopts = concat (std_shortopts, md_shortopts, (char *) NULL);
longopts = (struct option *) xmalloc (sizeof (std_longopts)
+ md_longopts_size + sizeof (struct option));
memcpy (longopts, std_longopts, sizeof (std_longopts));
memcpy (((char *) longopts) + sizeof (std_longopts), md_longopts, md_longopts_size);
memset (((char *) longopts) + sizeof (std_longopts) + md_longopts_size,
0, sizeof (struct option));
/* Make a local copy of the old argv. */
old_argc = *pargc;
old_argv = *pargv;
/* Initialize a new argv that contains no options. */
new_argv = notes_alloc (sizeof (char *) * (old_argc + 1));
new_argv[0] = old_argv[0];
new_argc = 1;
new_argv[new_argc] = NULL;
while (1)
{
/* getopt_long_only is like getopt_long, but '-' as well as '--' can
indicate a long option. */
int longind;
int optc = getopt_long_only (old_argc, old_argv, shortopts, longopts,
&longind);
if (optc == -1)
break;
switch (optc)
{
default:
/* md_parse_option should return 1 if it recognizes optc,
0 if not. */
if (md_parse_option (optc, optarg) != 0)
break;
/* `-v' isn't included in the general short_opts list, so check for
it explicitly here before deciding we've gotten a bad argument. */
if (optc == 'v')
{
#ifdef VMS
/* Telling getopt to treat -v's value as optional can result
in it picking up a following filename argument here. The
VMS code in md_parse_option can return 0 in that case,
but it has no way of pushing the filename argument back. */
if (optarg && *optarg)
new_argv[new_argc++] = optarg, new_argv[new_argc] = NULL;
else
#else
case 'v':
#endif
case OPTION_VERBOSE:
print_version_id ();
verbose = 1;
break;
}
else
as_bad (_("unrecognized option -%c%s"), optc, optarg ? optarg : "");
/* Fall through. */
case '?':
exit (EXIT_FAILURE);
case 1: /* File name. */
if (!strcmp (optarg, "-"))
optarg = (char *) "";
new_argv[new_argc++] = optarg;
new_argv[new_argc] = NULL;
break;
case OPTION_TARGET_HELP:
md_show_usage (stdout);
exit (EXIT_SUCCESS);
case OPTION_HELP:
show_usage (stdout);
exit (EXIT_SUCCESS);
case OPTION_NOCPP:
break;
case OPTION_NO_PAD_SECTIONS:
do_not_pad_sections_to_alignment = 1;
break;
case OPTION_STATISTICS:
flag_print_statistics = 1;
break;
case OPTION_STRIP_LOCAL_ABSOLUTE:
flag_strip_local_absolute = 1;
break;
case OPTION_TRADITIONAL_FORMAT:
flag_traditional_format = 1;
break;
case OPTION_MULTIBYTE_HANDLING:
if (strcmp (optarg, "allow") == 0)
multibyte_handling = multibyte_allow;
else if (strcmp (optarg, "warn") == 0)
multibyte_handling = multibyte_warn;
else if (strcmp (optarg, "warn-sym-only") == 0)
multibyte_handling = multibyte_warn_syms;
else if (strcmp (optarg, "warn_sym_only") == 0)
multibyte_handling = multibyte_warn_syms;
else
as_fatal (_("unexpected argument to --multibyte-input-option: '%s'"), optarg);
break;
case OPTION_VERSION:
/* This output is intended to follow the GNU standards document. */
printf (_("GNU assembler %s\n"), BFD_VERSION_STRING);
printf (_("Copyright (C) 2024 Free Software Foundation, Inc.\n"));
printf (_("\
This program is free software; you may redistribute it under the terms of\n\
the GNU General Public License version 3 or later.\n\
This program has absolutely no warranty.\n"));
#ifdef TARGET_WITH_CPU
printf (_("This assembler was configured for a target of `%s' "
"and default,\ncpu type `%s'.\n"),
TARGET_ALIAS, TARGET_WITH_CPU);
#else
printf (_("This assembler was configured for a target of `%s'.\n"),
TARGET_ALIAS);
#endif
exit (EXIT_SUCCESS);
case OPTION_EMULATION:
#ifdef USE_EMULATIONS
if (strcmp (optarg, this_emulation->name))
as_fatal (_("multiple emulation names specified"));
#else
as_fatal (_("emulations not handled in this configuration"));
#endif
break;
case OPTION_DUMPCONFIG:
fprintf (stderr, _("alias = %s\n"), TARGET_ALIAS);
fprintf (stderr, _("canonical = %s\n"), TARGET_CANONICAL);
fprintf (stderr, _("cpu-type = %s\n"), TARGET_CPU);
#ifdef TARGET_OBJ_FORMAT
fprintf (stderr, _("format = %s\n"), TARGET_OBJ_FORMAT);
#endif
#ifdef TARGET_FORMAT
fprintf (stderr, _("bfd-target = %s\n"), TARGET_FORMAT);
#endif
exit (EXIT_SUCCESS);
case OPTION_COMPRESS_DEBUG:
if (optarg)
{
#if defined OBJ_ELF || defined OBJ_MAYBE_ELF
flag_compress_debug = bfd_get_compression_algorithm (optarg);
#ifndef HAVE_ZSTD
if (flag_compress_debug == COMPRESS_DEBUG_ZSTD)
as_fatal (_ ("--compress-debug-sections=zstd: gas is not "
"built with zstd support"));
#endif
if (flag_compress_debug == COMPRESS_UNKNOWN)
as_fatal (_("Invalid --compress-debug-sections option: `%s'"),
optarg);
#else
as_fatal (_("--compress-debug-sections=%s is unsupported"),
optarg);
#endif
}
else
flag_compress_debug = DEFAULT_COMPRESSED_DEBUG_ALGORITHM;
break;
case OPTION_NOCOMPRESS_DEBUG:
flag_compress_debug = COMPRESS_DEBUG_NONE;
break;
case OPTION_DEBUG_PREFIX_MAP:
add_debug_prefix_map (optarg);
break;
case OPTION_DEFSYM:
{
char *s;
valueT i;
struct defsym_list *n;
for (s = optarg; *s != '\0' && *s != '='; s++)
;
if (*s == '\0')
as_fatal (_("bad defsym; format is --defsym name=value"));
*s++ = '\0';
i = bfd_scan_vma (s, (const char **) NULL, 0);
n = XNEW (struct defsym_list);
n->next = defsyms;
n->name = optarg;
n->value = i;
defsyms = n;
}
break;
#ifdef HAVE_ITBL_CPU
case 't':
{
/* optarg is the name of the file containing the instruction
formats, opcodes, register names, etc. */
if (optarg == NULL)
{
as_warn (_("no file name following -t option"));
break;
}
/* Parse the file and add the new instructions to our internal
table. If multiple instruction tables are specified, the
information from this table gets appended onto the existing
internal table. */
if (itbl_parse (optarg) != 0)
as_fatal (_("failed to read instruction table %s\n"),
optarg);
}
break;
#endif
case OPTION_DEPFILE:
start_dependencies (optarg);
break;
case 'g':
/* Some backends, eg Alpha and Mips, use the -g switch for their
own purposes. So we check here for an explicit -g and allow
the backend to decide if it wants to process it. */
if ( old_argv[optind - 1][1] == 'g'
&& md_parse_option (optc, optarg))
continue;
/* We end up here for any -gsomething-not-already-a-long-option.
give some useful feedback on not (yet) supported -gdwarfxxx
versions/sections/options. */
if (startswith (old_argv[optind - 1], "-gdwarf"))
as_fatal (_("unknown DWARF option %s\n"), old_argv[optind - 1]);
else if (old_argv[optind - 1][1] == 'g' && optarg != NULL)
as_fatal (_("unknown option `%s'"), old_argv[optind - 1]);
if (md_debug_format_selector)
debug_type = md_debug_format_selector (& use_gnu_debug_info_extensions);
else if (IS_ELF)
{
debug_type = DEBUG_DWARF2;
dwarf_level = 2;
}
else
debug_type = DEBUG_STABS;
break;
case OPTION_GSTABS_PLUS:
use_gnu_debug_info_extensions = 1;
/* Fall through. */
case OPTION_GSTABS:
debug_type = DEBUG_STABS;
break;
case OPTION_GDWARF_2:
debug_type = DEBUG_DWARF2;
dwarf_level = 2;
break;
case OPTION_GDWARF_3:
debug_type = DEBUG_DWARF2;
dwarf_level = 3;
break;
case OPTION_GDWARF_4:
debug_type = DEBUG_DWARF2;
dwarf_level = 4;
break;
case OPTION_GDWARF_5:
debug_type = DEBUG_DWARF2;
dwarf_level = 5;
break;
case OPTION_GDWARF_SECTIONS:
flag_dwarf_sections = true;
break;
#if defined (TE_PE) && defined (O_secrel)
case OPTION_GCODEVIEW:
debug_type = DEBUG_CODEVIEW;
break;
#endif
case OPTION_GDWARF_CIE_VERSION:
flag_dwarf_cie_version = atoi (optarg);
/* The available CIE versions are 1 (DWARF 2), 3 (DWARF 3), and 4
(DWARF 4 and 5). */
if (flag_dwarf_cie_version < 1
|| flag_dwarf_cie_version == 2
|| flag_dwarf_cie_version > 4)
as_fatal (_("Invalid --gdwarf-cie-version `%s'"), optarg);
switch (flag_dwarf_cie_version)
{
case 1:
if (dwarf_level < 2)
dwarf_level = 2;
break;
case 3:
if (dwarf_level < 3)
dwarf_level = 3;
break;
default:
if (dwarf_level < 4)
dwarf_level = 4;
break;
}
break;
case 'J':
flag_signed_overflow_ok = 1;
break;
#ifndef WORKING_DOT_WORD
case 'K':
flag_warn_displacement = 1;
break;
#endif
case 'L':
flag_keep_locals = 1;
break;
case OPTION_LISTING_LHS_WIDTH:
listing_lhs_width = atoi (optarg);
if (listing_lhs_width_second < listing_lhs_width)
listing_lhs_width_second = listing_lhs_width;
break;
case OPTION_LISTING_LHS_WIDTH2:
{
int tmp = atoi (optarg);
if (tmp > listing_lhs_width)
listing_lhs_width_second = tmp;
}
break;
case OPTION_LISTING_RHS_WIDTH:
listing_rhs_width = atoi (optarg);
break;
case OPTION_LISTING_CONT_LINES:
listing_lhs_cont_lines = atoi (optarg);
break;
case 'M':
flag_mri = 1;
#ifdef TC_M68K
flag_m68k_mri = 1;
#endif
break;
case 'R':
flag_readonly_data_in_text = 1;
break;
case 'W':
flag_no_warnings = 1;
break;
case OPTION_WARN:
flag_no_warnings = 0;
flag_fatal_warnings = 0;
break;
case OPTION_WARN_FATAL:
flag_no_warnings = 0;
flag_fatal_warnings = 1;
break;
#if defined OBJ_ELF || defined OBJ_MAYBE_ELF
case OPTION_EXECSTACK:
flag_execstack = 1;
flag_noexecstack = 0;
break;
case OPTION_NOEXECSTACK:
flag_noexecstack = 1;
flag_execstack = 0;
break;
# if defined (TARGET_USE_SCFI) && defined (TARGET_USE_GINSN)
case OPTION_SCFI:
if (optarg && strcasecmp (optarg, "experimental") == 0)
flag_synth_cfi = SYNTH_CFI_EXPERIMENTAL;
else
as_fatal (_("Invalid --scfi= option: `%s'; suggested option: experimental"),
optarg);
break;
# endif
case OPTION_SIZE_CHECK:
if (strcasecmp (optarg, "error") == 0)
flag_allow_nonconst_size = false;
else if (strcasecmp (optarg, "warning") == 0)
flag_allow_nonconst_size = true;
else
as_fatal (_("Invalid --size-check= option: `%s'"), optarg);
break;
case OPTION_ELF_STT_COMMON:
if (strcasecmp (optarg, "no") == 0)
flag_use_elf_stt_common = 0;
else if (strcasecmp (optarg, "yes") == 0)
flag_use_elf_stt_common = 1;
else
as_fatal (_("Invalid --elf-stt-common= option: `%s'"),
optarg);
break;
case OPTION_SECTNAME_SUBST:
flag_sectname_subst = 1;
break;
case OPTION_ELF_BUILD_NOTES:
if (strcasecmp (optarg, "no") == 0)
flag_generate_build_notes = false;
else if (strcasecmp (optarg, "yes") == 0)
flag_generate_build_notes = true;
else
as_fatal (_("Invalid --generate-missing-build-notes option: `%s'"),
optarg);
break;
case OPTION_SFRAME:
flag_gen_sframe = 1;
break;
#endif /* OBJ_ELF */
case 'Z':
flag_always_generate_output = 1;
break;
case OPTION_AL:
listing |= LISTING_LISTING;
if (optarg)
listing_filename = notes_strdup (optarg);
break;
case OPTION_ALTERNATE:
optarg = old_argv [optind - 1];
while (* optarg == '-')
optarg ++;
if (strcmp (optarg, "alternate") == 0)
{
flag_macro_alternate = 1;
break;
}
optarg ++;
/* Fall through. */
case 'a':
if (optarg)
{
if (optarg != old_argv[optind] && optarg[-1] == '=')
--optarg;
if (md_parse_option (optc, optarg) != 0)
break;
while (*optarg)
{
switch (*optarg)
{
case 'c':
listing |= LISTING_NOCOND;
break;
case 'd':
listing |= LISTING_NODEBUG;
break;
case 'g':
listing |= LISTING_GENERAL;
break;
case 'h':
listing |= LISTING_HLL;
break;
case 'i':
listing |= LISTING_GINSN_SCFI;
break;
case 'l':
listing |= LISTING_LISTING;
break;
case 'm':
listing |= LISTING_MACEXP;
break;
case 'n':
listing |= LISTING_NOFORM;
break;
case 's':
listing |= LISTING_SYMBOLS;
break;
case '=':
listing_filename = notes_strdup (optarg + 1);
optarg += strlen (listing_filename);
break;
default:
as_fatal (_("invalid listing option `%c'"), *optarg);
break;
}
optarg++;
}
}
if (!listing)
listing = LISTING_DEFAULT;
break;
case 'D':
/* DEBUG is implemented: it debugs different
things from other people's assemblers. */
flag_debug = 1;
break;
case 'f':
flag_no_comments = 1;
break;
case 'I':
{ /* Include file directory. */
char *temp = notes_strdup (optarg);
add_include_dir (temp);
break;
}
case 'o':
out_file_name = notes_strdup (optarg);
break;
case 'w':
break;
case 'X':
/* -X means treat warnings as errors. */
break;
case OPTION_REDUCE_MEMORY_OVERHEADS:
break;
case OPTION_HASH_TABLE_SIZE:
break;
}
}
free (shortopts);
free (longopts);
*pargc = new_argc;
*pargv = new_argv;
#ifdef md_after_parse_args
md_after_parse_args ();
#endif
}
static void
dump_statistics (void)
{
long run_time = get_run_time () - start_time;
fprintf (stderr, _("%s: total time in assembly: %ld.%06ld\n"),
myname, run_time / 1000000, run_time % 1000000);
subsegs_print_statistics (stderr);
write_print_statistics (stderr);
symbol_print_statistics (stderr);
read_print_statistics (stderr);
#ifdef tc_print_statistics
tc_print_statistics (stderr);
#endif
#ifdef obj_print_statistics
obj_print_statistics (stderr);
#endif
}
/* Here to attempt 1 pass over each input file.
We scan argv[*] looking for filenames or exactly "" which is
shorthand for stdin. Any argv that is NULL is not a file-name.
We set need_pass_2 TRUE if, after this, we still have unresolved
expressions of the form (unknown value)+-(unknown value).
Note the un*x semantics: there is only 1 logical input file, but it
may be a catenation of many 'physical' input files. */
static void
perform_an_assembly_pass (int argc, char ** argv)
{
int saw_a_file = 0;
#ifndef OBJ_MACH_O
flagword applicable;
#endif
need_pass_2 = 0;
#ifndef OBJ_MACH_O
/* Create the standard sections, and those the assembler uses
internally. */
text_section = subseg_new (TEXT_SECTION_NAME, 0);
data_section = subseg_new (DATA_SECTION_NAME, 0);
bss_section = subseg_new (BSS_SECTION_NAME, 0);
/* @@ FIXME -- we're setting the RELOC flag so that sections are assumed
to have relocs, otherwise we don't find out in time. */
applicable = bfd_applicable_section_flags (stdoutput);
bfd_set_section_flags (text_section,
applicable & (SEC_ALLOC | SEC_LOAD | SEC_RELOC
| SEC_CODE | SEC_READONLY));
bfd_set_section_flags (data_section,
applicable & (SEC_ALLOC | SEC_LOAD | SEC_RELOC
| SEC_DATA));
bfd_set_section_flags (bss_section, applicable & SEC_ALLOC);
seg_info (bss_section)->bss = 1;
#endif
subseg_new (BFD_ABS_SECTION_NAME, 0);
subseg_new (BFD_UND_SECTION_NAME, 0);
reg_section = subseg_new ("*GAS `reg' section*", 0);
expr_section = subseg_new ("*GAS `expr' section*", 0);
#ifndef OBJ_MACH_O
subseg_set (text_section, 0);
#endif
/* This may add symbol table entries, which requires having an open BFD,
and sections already created. */
md_begin ();
#ifdef USING_CGEN
gas_cgen_begin ();
#endif
#ifdef obj_begin
obj_begin ();
#endif
/* Skip argv[0]. */
argv++;
argc--;
while (argc--)
{
if (*argv)
{ /* Is it a file-name argument? */
saw_a_file++;
/* argv->"" if stdin desired, else->filename. */
read_a_source_file (*argv);
}
argv++; /* Completed that argv. */
}
if (!saw_a_file)
read_a_source_file ("");
}
static void
free_notes (void)
{
_obstack_free (&notes, NULL);
}
/* Early initialisation, before gas prints messages. */
static void
gas_early_init (int *argcp, char ***argvp)
{
start_time = get_run_time ();
signal_init ();
#ifdef HAVE_LC_MESSAGES
setlocale (LC_MESSAGES, "");
#endif
setlocale (LC_CTYPE, "");
bindtextdomain (PACKAGE, LOCALEDIR);
textdomain (PACKAGE);
if (debug_memory)
chunksize = 64;
#ifndef OBJ_DEFAULT_OUTPUT_FILE_NAME
#define OBJ_DEFAULT_OUTPUT_FILE_NAME "a.out"
#endif
out_file_name = OBJ_DEFAULT_OUTPUT_FILE_NAME;
hex_init ();
if (bfd_init () != BFD_INIT_MAGIC)
as_fatal (_("libbfd ABI mismatch"));
obstack_begin (&notes, chunksize);
xatexit (free_notes);
myname = **argvp;
xmalloc_set_program_name (myname);
bfd_set_error_program_name (myname);
expandargv (argcp, argvp);
init_include_dir ();
#ifdef HOST_SPECIAL_INIT
HOST_SPECIAL_INIT (*argcp, *argvp);
#endif
#ifdef USE_EMULATIONS
select_emulation_mode (*argcp, *argvp);
#endif
}
/* The bulk of gas initialisation. This is after args are parsed. */
static void
gas_init (void)
{
symbol_begin ();
frag_init ();
subsegs_begin ();
read_begin ();
input_scrub_begin ();
expr_begin ();
eh_begin ();
macro_init ();
dwarf2_init ();
local_symbol_make (".gasversion.", absolute_section,
&predefined_address_frag, BFD_VERSION / 10000UL);
/* Note: Put new initialisation calls that don't depend on stdoutput
being open above this point. stdoutput must be open for anything
that might use stdoutput objalloc memory, eg. calling bfd_alloc
or creating global symbols (via bfd_make_empty_symbol). */
xatexit (output_file_close);
output_file_create (out_file_name);
gas_assert (stdoutput != 0);
/* Must be called before output_file_close. xexit calls the xatexit
list in reverse order. */
if (flag_print_statistics)
xatexit (dump_statistics);
dot_symbol_init ();
#ifdef tc_init_after_args
tc_init_after_args ();
#endif
itbl_init ();
/* Now that we have fully initialized, and have created the output
file, define any symbols requested by --defsym command line
arguments. */
while (defsyms != NULL)
{
symbolS *sym;
struct defsym_list *next;
sym = symbol_new (defsyms->name, absolute_section,
&zero_address_frag, defsyms->value);
/* Make symbols defined on the command line volatile, so that they
can be redefined inside a source file. This makes this assembler's
behaviour compatible with earlier versions, but it may not be
completely intuitive. */
S_SET_VOLATILE (sym);
symbol_table_insert (sym);
next = defsyms->next;
free (defsyms);
defsyms = next;
}
}
int
main (int argc, char ** argv)
{
char ** argv_orig = argv;
struct stat sob;
gas_early_init (&argc, &argv);
/* Call parse_args before gas_init so that switches like
--hash-size can be honored. */
parse_args (&argc, &argv);
if (argc > 1 && stat (out_file_name, &sob) == 0)
{
int i;
for (i = 1; i < argc; ++i)
{
struct stat sib;
/* Check that the input file and output file are different. */
if (stat (argv[i], &sib) == 0
&& sib.st_ino == sob.st_ino
/* POSIX emulating systems may support stat() but if the
underlying file system does not support a file serial number
of some kind then they will return 0 for the inode. So
two files with an inode of 0 may not actually be the same.
On real POSIX systems no ordinary file will ever have an
inode of 0. */
&& sib.st_ino != 0
/* Different files may have the same inode number if they
reside on different devices, so check the st_dev field as
well. */
&& sib.st_dev == sob.st_dev
/* PR 25572: Only check regular files. Devices, sockets and so
on might actually work as both input and output. Plus there
is a use case for using /dev/null as both input and output
when checking for command line option support in a script:
as --foo /dev/null -o /dev/null; if $? then ... */
&& S_ISREG (sib.st_mode))
{
const char *saved_out_file_name = out_file_name;
/* Don't let as_fatal remove the output file! */
out_file_name = NULL;
as_fatal (_("The input '%s' and output '%s' files are the same"),
argv[i], saved_out_file_name);
}
}
}
gas_init ();
/* Assemble it. */
perform_an_assembly_pass (argc, argv);
cond_finish_check (-1);
#ifdef md_finish
md_finish ();
#endif
#if defined OBJ_ELF || defined OBJ_MAYBE_ELF
if ((flag_execstack || flag_noexecstack)
&& OUTPUT_FLAVOR == bfd_target_elf_flavour)
{
segT gnustack;
gnustack = subseg_new (".note.GNU-stack", 0);
bfd_set_section_flags (gnustack,
SEC_READONLY | (flag_execstack ? SEC_CODE : 0));
}
#endif
codeview_finish ();
/* If we've been collecting dwarf2 .debug_line info, either for
assembly debugging or on behalf of the compiler, emit it now. */
dwarf2_finish ();
/* If we constructed dwarf2 .eh_frame info, either via .cfi
directives from the user or by the backend, emit it now. */
cfi_finish ();
keep_it = 0;
if (seen_at_least_1_file ())
{
int n_warns, n_errs;
char warn_msg[50];
char err_msg[50];
write_object_file ();
n_warns = had_warnings ();
n_errs = had_errors ();
sprintf (warn_msg,
ngettext ("%d warning", "%d warnings", n_warns), n_warns);
sprintf (err_msg,
ngettext ("%d error", "%d errors", n_errs), n_errs);
if (flag_fatal_warnings && n_warns != 0)
{
if (n_errs == 0)
as_bad (_("%s, treating warnings as errors"), warn_msg);
n_errs += n_warns;
}
if (n_errs == 0)
keep_it = 1;
else if (flag_always_generate_output)
{
/* The -Z flag indicates that an object file should be generated,
regardless of warnings and errors. */
keep_it = 1;
fprintf (stderr, _("%s, %s, generating bad object file\n"),
err_msg, warn_msg);
}
}
fflush (stderr);
#ifndef NO_LISTING
listing_print (listing_filename, argv_orig);
#endif
input_scrub_end ();
/* Use xexit instead of return, because under VMS environments they
may not place the same interpretation on the value given. */
if (had_errors () != 0)
xexit (EXIT_FAILURE);
/* Only generate dependency file if assembler was successful. */
print_dependencies ();
xexit (EXIT_SUCCESS);
}