svr4.h

早期freebsd实现

/* svr4.h  --  operating system specific defines to be used when
   targeting GCC for some generic System V Release 4 system.
   Copyright (C) 1991 Free Software Foundation, Inc.

   Written by Ron Guilmette ([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, 675 Mass Ave, Cambridge, MA 02139, USA.

   To use this file, make up a file with a name like:

	?????svr4.h

   where ????? is replaced by the name of the basic hardware that you
   are targeting for.  Then, in the file ?????svr4.h, put something
   like:

	#include "?????.h"
	#include "svr4.h"

   followed by any really system-specific defines (or overrides of
   defines) which you find that you need.  For example, CPP_PREDEFINES
   is defined here with only the defined -Dunix and -DSVR4.  You should
   probably override that in your target-specific ?????svr4.h file
   with a set of defines that includes these, but also contains an
   appropriate define for the type of hardware that you are targeting.
*/

/* 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)			\
 (!strcmp (STR, "include") || !strcmp (STR, "imacros")	\
  || !strcmp (STR, "aux-info"))

/* 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 \
  "%{V} %{v:%{!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:-}"

/* Under svr4, the normal location of the `ld' and `as' programs is the
   /usr/ccs/bin directory.  */

#undef MD_EXEC_PREFIX
#define MD_EXEC_PREFIX "/usr/ccs/bin/"

/* Under svr4, the normal location of the various *crt*.o files is the
   /usr/ccs/lib directory.  */

#undef MD_STARTFILE_PREFIX
#define MD_STARTFILE_PREFIX "/usr/ccs/lib/"

/* Provide a LIB_SPEC appropriate for svr4.  Here we tack on the default
   standard C library (unless we are building a shared library) followed by
   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	LIB_SPEC
#define LIB_SPEC \
  "%{!shared:%{!symbolic:-lc}} \
  crtend.o%s \
  %{!shared:%{!symbolic:%{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
   -h*, -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:%{!V:-V}} \
		   %{b} %{Wl,*:%*} \
		   %{static:-dn -Bstatic} \
		   %{shared:-G -dy} \
		   %{symbolic:-Bsymbolic -G -dy} \
		   %{G:-G} \
		   %{YP,*} \
		   %{!YP,*:%{p:-Y P,/usr/ccs/lib/libp:/usr/lib/libp:/usr/ccs/lib:/usr/lib} \
		    %{!p:-Y P,/usr/ccs/lib:/usr/lib}} \
		   %{Qy:} %{!Qn:-Qy}"

/* Gcc automatically adds in one of the files /usr/ccs/lib/values-Xc.o,
   /usr/ccs/lib/values-Xa.o, or /usr/ccs/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 {				 				\
     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

/* Define the actual types of some ANSI-mandated types.  (These
   definitions should work for most SVR4 systems).  */

#undef SIZE_TYPE
#define SIZE_TYPE "unsigned int"

#undef PTRDIFF_TYPE
#define PTRDIFF_TYPE "int"

#undef WCHAR_TYPE
#define WCHAR_TYPE "long int"

#undef WCHAR_TYPE_SIZE
#define WCHAR_TYPE_SIZE BITS_PER_WORD

/* This causes trouble, because it requires the host machine
   to support ANSI C.  */
/* #define MULTIBYTE_CHARS */

#undef ASM_BYTE_OP
#define ASM_BYTE_OP	".byte"

#undef SET_ASM_OP
#define SET_ASM_OP	".set"

/* This is how to begin an assembly language file.  Most svr4 assemblers want
   at least a .file directive to come first, and some want to see a .version
   directive come right after that.  Here we just establish a default
   which generates only the .file directive.  If you need a .version
   directive for any specific target, you should override this definition
   in the target-specific file which includes this one.  */

#undef ASM_FILE_START
#define ASM_FILE_START(FILE)                                    \
  output_file_directive ((FILE), main_input_filename)

/* This is how to allocate empty space in some section.  The .zero
   pseudo-op is used for this on most svr4 assemblers.  */

#define SKIP_ASM_OP	".zero"

#undef ASM_OUTPUT_SKIP
#define ASM_OUTPUT_SKIP(FILE,SIZE) \
  fprintf (FILE, "\t%s\t%u\n", SKIP_ASM_OP, (SIZE))

/* This is how to output a reference to a user-level label named NAME.
   `assemble_name' uses this.

   For System V Release 4 the convention is *not* to prepend a leading
   underscore onto user-level symbol names.  */

#undef ASM_OUTPUT_LABELREF
#define ASM_OUTPUT_LABELREF(FILE,NAME) fprintf (FILE, "%s", NAME)

/* This is how to output an internal numbered label where
   PREFIX is the class of label and NUM is the number within the class.

   For most svr4 systems, the convention is that any symbol which begins
   with a period is not put into the linker symbol table by the assembler.  */

#undef ASM_OUTPUT_INTERNAL_LABEL
#define ASM_OUTPUT_INTERNAL_LABEL(FILE, PREFIX, NUM)			\
do {									\
  fprintf (FILE, ".%s%d:\n", PREFIX, NUM);				\
} while (0)

/* This is how to store into the string LABEL
   the symbol_ref name of an internal numbered label where
   PREFIX is the class of label and NUM is the number within the class.
   This is suitable for output with `assemble_name'.

   For most svr4 systems, the convention is that any symbol which begins
   with a period is not put into the linker symbol table by the assembler.  */

#undef ASM_GENERATE_INTERNAL_LABEL
#define ASM_GENERATE_INTERNAL_LABEL(LABEL, PREFIX, NUM)			\
do {									\
  sprintf (LABEL, "*.%s%d", PREFIX, NUM);				\
} while (0)

/* Output the label which preceeds a jumptable.  Note that for all svr4
   systems where we actually generate jumptables (which is to say every
   svr4 target except i386, where we use casesi instead) we put the jump-
   tables into the .rodata section and since other stuff could have been
   put into the .rodata section prior to any given jumptable, we have to
   make sure that the location counter for the .rodata section gets pro-
   perly re-aligned prior to the actual beginning of the jump table.  */

#define ALIGN_ASM_OP ".align"

#ifndef ASM_OUTPUT_BEFORE_CASE_LABEL
#define ASM_OUTPUT_BEFORE_CASE_LABEL(FILE,PREFIX,NUM,TABLE) \
  ASM_OUTPUT_ALIGN ((FILE), 2);
#endif

#undef ASM_OUTPUT_CASE_LABEL
#define ASM_OUTPUT_CASE_LABEL(FILE,PREFIX,NUM,JUMPTABLE)		\
  do {									\
    ASM_OUTPUT_BEFORE_CASE_LABEL (FILE, PREFIX, NUM, JUMPTABLE)		\
    ASM_OUTPUT_INTERNAL_LABEL (FILE, PREFIX, NUM);			\
  } while (0)

/* The standard SVR4 assembler seems to require that certain builtin
   library routines (e.g. .udiv) be explicitly declared as .globl
   in each assembly file where they are referenced.  */

#define ASM_OUTPUT_EXTERNAL_LIBCALL(FILE, FUN)				\
  ASM_GLOBALIZE_LABEL (FILE, XSTR (FUN, 0))

/* This says how to output assembler code to declare an
   uninitialized external linkage data object.  Under SVR4,
   the linker seems to want the alignment of data objects
   to depend on their types.  We do exactly that here.  */

#define COMMON_ASM_OP	".comm"

#undef ASM_OUTPUT_ALIGNED_COMMON
#define ASM_OUTPUT_ALIGNED_COMMON(FILE, NAME, SIZE, ALIGN)		\
do {									\
  fprintf ((FILE), "\t%s\t", COMMON_ASM_OP);				\
  assemble_name ((FILE), (NAME));					\
  fprintf ((FILE), ",%u,%u\n", (SIZE), (ALIGN) / BITS_PER_UNIT);	\
} while (0)

/* This says how to output assembler code to declare an
   uninitialized internal linkage data object.  Under SVR4,
   the linker seems to want the alignment of data objects
   to depend on their types.  We do exactly that here.  */

#define LOCAL_ASM_OP	".local"