gcc.c

gcc关键代码

#ifdef TARGET_OPTION_TRANSLATE_TABLE
static const struct {
  const char *const option_found;
  const char *const replacements;
} target_option_translations[] =
{
  TARGET_OPTION_TRANSLATE_TABLE,
  { 0, 0 }
};
#endif

/* Translate the options described by *ARGCP and *ARGVP.
   Make a new vector and store it back in *ARGVP,
   and store its length in *ARGVC.  */

static void
translate_options (int *argcp, const char *const **argvp)
{
  int i;
  int argc = *argcp;
  const char *const *argv = *argvp;
  int newvsize = (argc + 2) * 2 * sizeof (const char *);
  const char **newv = xmalloc (newvsize);
  int newindex = 0;

  i = 0;
  newv[newindex++] = argv[i++];

  while (i < argc)
    {
#ifdef TARGET_OPTION_TRANSLATE_TABLE
      int tott_idx;

      for (tott_idx = 0;
	   target_option_translations[tott_idx].option_found;
	   tott_idx++)
	{
	  if (strcmp (target_option_translations[tott_idx].option_found,
		      argv[i]) == 0)
	    {
	      int spaces = 1;
	      const char *sp;
	      char *np;

	      for (sp = target_option_translations[tott_idx].replacements;
		   *sp; sp++)
		{
		  if (*sp == ' ')
		    spaces ++;
		}

	      newvsize += spaces * sizeof (const char *);
	      newv =  xrealloc (newv, newvsize);

	      sp = target_option_translations[tott_idx].replacements;
	      np = xstrdup (sp);

	      while (1)
		{
		  while (*np == ' ')
		    np++;
		  if (*np == 0)
		    break;
		  newv[newindex++] = np;
		  while (*np != ' ' && *np)
		    np++;
		  if (*np == 0)
		    break;
		  *np++ = 0;
		}

	      i ++;
	      break;
	    }
	}
      if (target_option_translations[tott_idx].option_found)
	continue;
#endif

      /* Translate -- options.  */
      if (argv[i][0] == '-' && argv[i][1] == '-')
	{
	  size_t j;
	  /* Find a mapping that applies to this option.  */
	  for (j = 0; j < ARRAY_SIZE (option_map); j++)
	    {
	      size_t optlen = strlen (option_map[j].name);
	      size_t arglen = strlen (argv[i]);
	      size_t complen = arglen > optlen ? optlen : arglen;
	      const char *arginfo = option_map[j].arg_info;

	      if (arginfo == 0)
		arginfo = "";

	      if (!strncmp (argv[i], option_map[j].name, complen))
		{
		  const char *arg = 0;

		  if (arglen < optlen)
		    {
		      size_t k;
		      for (k = j + 1; k < ARRAY_SIZE (option_map); k++)
			if (strlen (option_map[k].name) >= arglen
			    && !strncmp (argv[i], option_map[k].name, arglen))
			  {
			    error ("ambiguous abbreviation %s", argv[i]);
			    break;
			  }

		      if (k != ARRAY_SIZE (option_map))
			break;
		    }

		  if (arglen > optlen)
		    {
		      /* If the option has an argument, accept that.  */
		      if (argv[i][optlen] == '=')
			arg = argv[i] + optlen + 1;

		      /* If this mapping requires extra text at end of name,
			 accept that as "argument".  */
		      else if (strchr (arginfo, '*') != 0)
			arg = argv[i] + optlen;

		      /* Otherwise, extra text at end means mismatch.
			 Try other mappings.  */
		      else
			continue;
		    }

		  else if (strchr (arginfo, '*') != 0)
		    {
		      error ("incomplete '%s' option", option_map[j].name);
		      break;
		    }

		  /* Handle arguments.  */
		  if (strchr (arginfo, 'a') != 0)
		    {
		      if (arg == 0)
			{
			  if (i + 1 == argc)
			    {
			      error ("missing argument to '%s' option",
				     option_map[j].name);
			      break;
			    }

			  arg = argv[++i];
			}
		    }
		  else if (strchr (arginfo, '*') != 0)
		    ;
		  else if (strchr (arginfo, 'o') == 0)
		    {
		      if (arg != 0)
			error ("extraneous argument to '%s' option",
			       option_map[j].name);
		      arg = 0;
		    }

		  /* Store the translation as one argv elt or as two.  */
		  if (arg != 0 && strchr (arginfo, 'j') != 0)
		    newv[newindex++] = concat (option_map[j].equivalent, arg,
					       NULL);
		  else if (arg != 0)
		    {
		      newv[newindex++] = option_map[j].equivalent;
		      newv[newindex++] = arg;
		    }
		  else
		    newv[newindex++] = option_map[j].equivalent;

		  break;
		}
	    }
	  i++;
	}

      /* Handle old-fashioned options--just copy them through,
	 with their arguments.  */
      else if (argv[i][0] == '-')
	{
	  const char *p = argv[i] + 1;
	  int c = *p;
	  int nskip = 1;

	  if (SWITCH_TAKES_ARG (c) > (p[1] != 0))
	    nskip += SWITCH_TAKES_ARG (c) - (p[1] != 0);
	  else if (WORD_SWITCH_TAKES_ARG (p))
	    nskip += WORD_SWITCH_TAKES_ARG (p);
	  else if ((c == 'B' || c == 'b' || c == 'x')
		   && p[1] == 0)
	    nskip += 1;
	  else if (! strcmp (p, "Xlinker"))
	    nskip += 1;
	  else if (! strcmp (p, "Xpreprocessor"))
	    nskip += 1;
	  else if (! strcmp (p, "Xassembler"))
	    nskip += 1;

	  /* Watch out for an option at the end of the command line that
	     is missing arguments, and avoid skipping past the end of the
	     command line.  */
	  if (nskip + i > argc)
	    nskip = argc - i;

	  while (nskip > 0)
	    {
	      newv[newindex++] = argv[i++];
	      nskip--;
	    }
	}
      else
	/* Ordinary operands, or +e options.  */
	newv[newindex++] = argv[i++];
    }

  newv[newindex] = 0;

  *argvp = newv;
  *argcp = newindex;
}

static char *
skip_whitespace (char *p)
{
  while (1)
    {
      /* A fully-blank line is a delimiter in the SPEC file and shouldn't
	 be considered whitespace.  */
      if (p[0] == '\n' && p[1] == '\n' && p[2] == '\n')
	return p + 1;
      else if (*p == '\n' || *p == ' ' || *p == '\t')
	p++;
      else if (*p == '#')
	{
	  while (*p != '\n')
	    p++;
	  p++;
	}
      else
	break;
    }

  return p;
}
/* Structures to keep track of prefixes to try when looking for files.  */

struct prefix_list
{
  const char *prefix;	      /* String to prepend to the path.  */
  struct prefix_list *next;   /* Next in linked list.  */
  int require_machine_suffix; /* Don't use without machine_suffix.  */
  /* 2 means try both machine_suffix and just_machine_suffix.  */
  int priority;		      /* Sort key - priority within list.  */
  int os_multilib;	      /* 1 if OS multilib scheme should be used,
				 0 for GCC multilib scheme.  */
};

struct path_prefix
{
  struct prefix_list *plist;  /* List of prefixes to try */
  int max_len;                /* Max length of a prefix in PLIST */
  const char *name;           /* Name of this list (used in config stuff) */
};

/* List of prefixes to try when looking for executables.  */

static struct path_prefix exec_prefixes = { 0, 0, "exec" };

/* List of prefixes to try when looking for startup (crt0) files.  */

static struct path_prefix startfile_prefixes = { 0, 0, "startfile" };

/* List of prefixes to try when looking for include files.  */

static struct path_prefix include_prefixes = { 0, 0, "include" };

/* Suffix to attach to directories searched for commands.
   This looks like `MACHINE/VERSION/'.  */

static const char *machine_suffix = 0;

/* Suffix to attach to directories searched for commands.
   This is just `MACHINE/'.  */

static const char *just_machine_suffix = 0;

/* Adjusted value of GCC_EXEC_PREFIX envvar.  */

static const char *gcc_exec_prefix;

/* Adjusted value of standard_libexec_prefix.  */

static const char *gcc_libexec_prefix;

/* Default prefixes to attach to command names.  */

#ifndef STANDARD_STARTFILE_PREFIX_1
#define STANDARD_STARTFILE_PREFIX_1 "/lib/"
#endif
#ifndef STANDARD_STARTFILE_PREFIX_2
#define STANDARD_STARTFILE_PREFIX_2 "/usr/lib/"
#endif

#ifdef CROSS_COMPILE  /* Don't use these prefixes for a cross compiler.  */
#undef MD_EXEC_PREFIX
#undef MD_STARTFILE_PREFIX
#undef MD_STARTFILE_PREFIX_1
#endif

/* If no prefixes defined, use the null string, which will disable them.  */
#ifndef MD_EXEC_PREFIX
#define MD_EXEC_PREFIX ""
#endif
#ifndef MD_STARTFILE_PREFIX
#define MD_STARTFILE_PREFIX ""
#endif
#ifndef MD_STARTFILE_PREFIX_1
#define MD_STARTFILE_PREFIX_1 ""
#endif

static const char *const standard_exec_prefix = STANDARD_EXEC_PREFIX;
static const char *const standard_exec_prefix_1 = "/usr/libexec/gcc/";
static const char *const standard_exec_prefix_2 = "/usr/lib/gcc/";
static const char *md_exec_prefix = MD_EXEC_PREFIX;

static const char *md_startfile_prefix = MD_STARTFILE_PREFIX;
static const char *md_startfile_prefix_1 = MD_STARTFILE_PREFIX_1;
static const char *const standard_startfile_prefix = STANDARD_STARTFILE_PREFIX;
static const char *const standard_startfile_prefix_1
  = STANDARD_STARTFILE_PREFIX_1;
static const char *const standard_startfile_prefix_2
  = STANDARD_STARTFILE_PREFIX_2;

static const char *const tooldir_base_prefix = TOOLDIR_BASE_PREFIX;
static const char *tooldir_prefix;

static const char *const standard_bindir_prefix = STANDARD_BINDIR_PREFIX;

static const char *standard_libexec_prefix = STANDARD_LIBEXEC_PREFIX;

/* Subdirectory to use for locating libraries.  Set by
   set_multilib_dir based on the compilation options.  */

static const char *multilib_dir;

/* Subdirectory to use for locating libraries in OS conventions.  Set by
   set_multilib_dir based on the compilation options.  */

static const char *multilib_os_dir;

/* Structure to keep track of the specs that have been defined so far.
   These are accessed using %(specname) or %[specname] in a compiler
   or link spec.  */

struct spec_list
{
				/* The following 2 fields must be first */
				/* to allow EXTRA_SPECS to be initialized */
  const char *name;		/* name of the spec.  */
  const char *ptr;		/* available ptr if no static pointer */

				/* The following fields are not initialized */
				/* by EXTRA_SPECS */
  const char **ptr_spec;	/* pointer to the spec itself.  */
  struct spec_list *next;	/* Next spec in linked list.  */
  int name_len;			/* length of the name */
  int alloc_p;			/* whether string was allocated */
};

#define INIT_STATIC_SPEC(NAME,PTR) \
{ NAME, NULL, PTR, (struct spec_list *) 0, sizeof (NAME) - 1, 0 }

/* List of statically defined specs.  */
static struct spec_list static_specs[] =
{
  INIT_STATIC_SPEC ("asm",			&asm_spec),