ptx4.h

gcc-2.95.3 Linux下最常用的C编译器

/* Operating system specific defines to be used when targeting GCC for some
   generic System V Release 4 system.
   Copyright (C) 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
   Contributed by Ron Guilmette ([e-mail]).
   Renamed and changed to suit Dynix/ptx v4 and later.
   Modified by Tim Wright ([e-mail]).
  
This file is part of GNU CC.

GNU CC 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 2, or (at your option)
any later version.

GNU CC 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 GNU CC; see the file COPYING.  If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.

*/

/* Define a symbol indicating that we are using svr4.h.  */
#define USING_SVR4_H

/* For the sake of libgcc2.c, indicate target supports atexit.  */
#define HAVE_ATEXIT

/* Cpp, assembler, linker, library, and startfile spec's.  */

/* This defines which switch letters take arguments.  On svr4, most of
   the normal cases (defined in gcc.c) apply, and we also have -h* and
   -z* options (for the linker).  Note however that there is no such
   thing as a -T option for svr4.  */

#define SWITCH_TAKES_ARG(CHAR) \
  (   (CHAR) == 'D' \
   || (CHAR) == 'U' \
   || (CHAR) == 'o' \
   || (CHAR) == 'e' \
   || (CHAR) == 'u' \
   || (CHAR) == 'I' \
   || (CHAR) == 'm' \
   || (CHAR) == 'L' \
   || (CHAR) == 'A' \
   || (CHAR) == 'h' \
   || (CHAR) == 'z')

/* This defines which multi-letter switches take arguments.  On svr4,
   there are no such switches except those implemented by GCC itself.  */

#define WORD_SWITCH_TAKES_ARG(STR)			\
 (DEFAULT_WORD_SWITCH_TAKES_ARG (STR)			\
  && strcmp (STR, "Tdata") && strcmp (STR, "Ttext")	\
  && strcmp (STR, "Tbss"))

/* You should redefine CPP_PREDEFINES in any file which includes this one.
   The definition should be appropriate for the type of target system
   involved, and it should include any -A (assertion) options which are
   appropriate for the given target system.  */
#undef CPP_PREDEFINES

/* Provide an ASM_SPEC appropriate for svr4.  Here we try to support as
   many of the specialized svr4 assembler options as seems reasonable,
   given that there are certain options which we can't (or shouldn't)
   support directly due to the fact that they conflict with other options 
   for other svr4 tools (e.g. ld) or with other options for GCC itself.
   For example, we don't support the -o (output file) or -R (remove
   input file) options because GCC already handles these things.  We
   also don't support the -m (run m4) option for the assembler because
   that conflicts with the -m (produce load map) option of the svr4
   linker.  We do however allow passing arbitrary options to the svr4
   assembler via the -Wa, option.

   Note that gcc doesn't allow a space to follow -Y in a -Ym,* or -Yd,*
   option.
*/

#undef ASM_SPEC
#define ASM_SPEC \
  "-no_0f_fix %{v:-V} %{Qy:} %{!Qn:-Qy} %{n} %{T} %{Ym,*} %{Yd,*} %{Wa,*:%*}"

/* svr4 assemblers need the `-' (indicating input from stdin) to come after
   the -o option (and its argument) for some reason.  If we try to put it
   before the -o option, the assembler will try to read the file named as
   the output file in the -o option as an input file (after it has already
   written some stuff to it) and the binary stuff contained therein will
   cause totally confuse the assembler, resulting in many spurious error
   messages.  */

#undef ASM_FINAL_SPEC
#define ASM_FINAL_SPEC "%{pipe:-}"

/* Provide a LIB_SPEC appropriate for svr4.  Here we tack on the default
   standard C library (unless we are building a shared library).  */

#undef	LIB_SPEC
#define LIB_SPEC "%{!shared:%{!symbolic:-lc}}"

/* Provide a LIBGCC_SPEC appropriate for svr4.  We also want to exclude
   libgcc when -symbolic.  */

#undef  LIBGCC_SPEC
#define LIBGCC_SPEC "%{!shared:%{!symbolic:-lgcc}}"

/* Provide an ENDFILE_SPEC appropriate for svr4.  Here we tack on our own
   magical crtend.o file (see crtstuff.c) which provides part of the
   support for getting C++ file-scope static object constructed before
   entering `main', followed by the normal svr3/svr4 "finalizer" file,
   which is either `gcrtn.o' or `crtn.o'.  */

#undef  ENDFILE_SPEC
#define ENDFILE_SPEC "crtend.o%s %{pg:gcrtn.o}%{!pg:crtn.o%s}"

/* Provide a LINK_SPEC appropriate for svr4.  Here we provide support
   for the special GCC options -static, -shared, and -symbolic which
   allow us to link things in one of these three modes by applying the
   appropriate combinations of options at link-time.  We also provide
   support here for as many of the other svr4 linker options as seems
   reasonable, given that some of them conflict with options for other
   svr4 tools (e.g. the assembler).  In particular, we do support the
   -z*, -V, -b, -t, -Qy, -Qn, and -YP* options here, and the -e*,
   -l*, -o*, -r, -s, -u*, and -L* options are directly supported
   by gcc.c itself.  We don't directly support the -m (generate load
   map) option because that conflicts with the -m (run m4) option of
   the svr4 assembler.  We also don't directly support the svr4 linker's
   -I* or -M* options because these conflict with existing GCC options.
   We do however allow passing arbitrary options to the svr4 linker
   via the -Wl, option.  We don't support the svr4 linker's -a option
   at all because it is totally useless and because it conflicts with
   GCC's own -a option.

   Note that gcc doesn't allow a space to follow -Y in a -YP,* option.

   When the -G link option is used (-shared and -symbolic) a final link is
   not being done.  */

#undef	LINK_SPEC
#define LINK_SPEC "%{h*} %{v:-V} \
		   %{b} %{Wl,*:%*} \
		   %{static:-dn -Bstatic} \
		   %{shared:-G -dy -z text} \
		   %{symbolic:-Bsymbolic -G -dy -z text} \
		   %{G:-G} \
		   %{YP,*} \
		   %{!YP,*:%{p:-Y P,/lib/libp:/usr/lib/libp:/lib:/usr/lib} \
		    %{!p:-Y P,/lib:/usr/lib}} \
		   %{Qy:} %{!Qn:-Qy}"

/* Gcc automatically adds in one of the files /lib/values-Xc.o,
   /lib/values-Xa.o, or /lib/values-Xt.o for each final link
   step (depending upon the other gcc options selected, such as
   -traditional and -ansi).  These files each contain one (initialized)
   copy of a special variable called `_lib_version'.  Each one of these
   files has `_lib_version' initialized to a different (enum) value.
   The SVR4 library routines query the value of `_lib_version' at run
   to decide how they should behave.  Specifically, they decide (based
   upon the value of `_lib_version') if they will act in a strictly ANSI
   conforming manner or not.
*/

#undef	STARTFILE_SPEC
#define STARTFILE_SPEC "%{!shared: \
			 %{!symbolic: \
			  %{pg:gcrt1.o%s}%{!pg:%{p:mcrt1.o%s}%{!p:crt1.o%s}}}}\
			%{pg:gcrti.o%s}%{!pg:crti.o%s} \
			%{ansi:values-Xc.o%s} \
			%{!ansi: \
			 %{traditional:values-Xt.o%s} \
			 %{!traditional:values-Xa.o%s}} \
 			crtbegin.o%s"

/* Attach a special .ident directive to the end of the file to identify
   the version of GCC which compiled this code.  The format of the
   .ident string is patterned after the ones produced by native svr4
   C compilers.  */

#define IDENT_ASM_OP ".ident"

#define ASM_FILE_END(FILE)					\
do {				 				\
     if (!flag_no_ident)					\
	fprintf ((FILE), "\t%s\t\"GCC: (GNU) %s\"\n",		\
		 IDENT_ASM_OP, version_string);			\
   } while (0)

/* Allow #sccs in preprocessor.  */

#define SCCS_DIRECTIVE

/* Output #ident as a .ident.  */

#define ASM_OUTPUT_IDENT(FILE, NAME) \
  fprintf (FILE, "\t%s\t\"%s\"\n", IDENT_ASM_OP, NAME);

/* Use periods rather than dollar signs in special g++ assembler names.  */

#define NO_DOLLAR_IN_LABEL

/* Writing `int' for a bitfield forces int alignment for the structure.  */

#define PCC_BITFIELD_TYPE_MATTERS 1

/* Implicit library calls should use memcpy, not bcopy, etc.  */

#define TARGET_MEM_FUNCTIONS

/* Handle #pragma weak and #pragma pack.  */

#define HANDLE_SYSV_PRAGMA

/* System V Release 4 uses DWARF debugging info.  */

#define DWARF_DEBUGGING_INFO

/* The numbers used to denote specific machine registers in the System V
   Release 4 DWARF debugging information are quite likely to be totally
   different from the numbers used in BSD stabs debugging information
   for the same kind of target machine.  Thus, we undefine the macro
   DBX_REGISTER_NUMBER here as an extra inducement to get people to
   provide proper machine-specific definitions of DBX_REGISTER_NUMBER
   (which is also used to provide DWARF registers numbers in dwarfout.c)
   in their tm.h files which include this file.  */

#undef DBX_REGISTER_NUMBER

/* gas on SVR4 supports the use of .stabs.  Permit -gstabs to be used
   in general, although it will only work when using gas.  */

#define DBX_DEBUGGING_INFO

/* Use DWARF debugging info by default.  */

#ifndef PREFERRED_DEBUGGING_TYPE
#define PREFERRED_DEBUGGING_TYPE DWARF_DEBUG
#endif

/* Make LBRAC and RBRAC addresses relative to the start of the
   function.  The native Solaris stabs debugging format works this
   way, gdb expects it, and it reduces the number of relocation
   entries.  */

#define DBX_BLOCKS_FUNCTION_RELATIVE 1

/* When using stabs, gcc2_compiled must be a stabs entry, not an
   ordinary symbol, or gdb won't see it.  The stabs entry must be
   before the N_SO in order for gdb to find it.  */

#define ASM_IDENTIFY_GCC(FILE)						\
do									\
  {									\
    if (write_symbols != DBX_DEBUG)					\
      fputs ("gcc2_compiled.:\n", FILE);				\
    else								\
      fputs ("\t.stabs\t\"gcc2_compiled.\", 0x3c, 0, 0, 0\n", FILE);	\
  }									\
while (0)

/* Like block addresses, stabs line numbers are relative to the
   current function.  */

#define ASM_OUTPUT_SOURCE_LINE(file, line)				\
do									\
  {									\
    static int sym_lineno = 1;						\
    fprintf (file, ".stabn 68,0,%d,.LM%d-",				\
	     line, sym_lineno);						\
    assemble_name (file,						\
		   XSTR (XEXP (DECL_RTL (current_function_decl), 0), 0));\
    fprintf (file, "\n.LM%d:\n", sym_lineno);				\
    sym_lineno += 1;							\
  }									\
while (0)

/* In order for relative line numbers to work, we must output the
   stabs entry for the function name first.  */

#define DBX_FUNCTION_FIRST

/* Generate a blank trailing N_SO to mark the end of the .o file, since
   we can't depend upon the linker to mark .o file boundaries with
   embedded stabs.  */