linux-elf.h

linux下的gcc编译器

/* Definitions for ARM running Linux-based GNU systems using ELF
   Copyright (C) 1993, 1994, 1997, 1998, 1999, 2000, 2001, 2002 
   Free Software Foundation, Inc.
   Contributed by Philip Blundell <[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 this program; see the file COPYING.  If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

/* elfos.h should have already been included.  Now just override
   any conflicting definitions and add any extras.  */

/* Run-time Target Specification.  */
#undef  TARGET_VERSION
#define TARGET_VERSION  fputs (" (ARM GNU/Linux with ELF)", stderr);

/* Do not assume anything about header files.  */
#define NO_IMPLICIT_EXTERN_C

/* Default is to use APCS-32 mode.  */
#undef  TARGET_DEFAULT
#define TARGET_DEFAULT (ARM_FLAG_APCS_32 | ARM_FLAG_MMU_TRAPS)

#define SUBTARGET_CPU_DEFAULT TARGET_CPU_arm6

#define SUBTARGET_EXTRA_LINK_SPEC " -m armelf_linux -p"

#undef  MULTILIB_DEFAULTS
#define MULTILIB_DEFAULTS \
	{ "marm", "mlittle-endian", "mhard-float", "mapcs-32", "mno-thumb-interwork" }

#define CPP_APCS_PC_DEFAULT_SPEC "-D__APCS_32__"

/* The GNU C++ standard library requires that these macros be defined.  */
#undef CPLUSPLUS_CPP_SPEC
#define CPLUSPLUS_CPP_SPEC "-D_GNU_SOURCE %(cpp)"

/* Now we define the strings used to build the spec file.  */
#define LIB_SPEC \
  "%{pthread:-lpthread} \
   %{shared:-lc} \
   %{!shared:%{profile:-lc_p}%{!profile:-lc}}"

#define LIBGCC_SPEC "%{msoft-float:-lfloat} -lgcc"

/* Provide a STARTFILE_SPEC appropriate for GNU/Linux.  Here we add
   the GNU/Linux magical crtbegin.o file (see crtstuff.c) which
   provides part of the support for getting C++ file-scope static
   object constructed before entering `main'. */
   
#undef  STARTFILE_SPEC
#define STARTFILE_SPEC \
  "%{!shared: \
     %{pg:gcrt1.o%s} %{!pg:%{p:gcrt1.o%s} \
		       %{!p:%{profile:gcrt1.o%s} \
			 %{!profile:crt1.o%s}}}} \
   crti.o%s %{!shared:crtbegin.o%s} %{shared:crtbeginS.o%s}"

/* Provide a ENDFILE_SPEC appropriate for GNU/Linux.  Here we tack on
   the GNU/Linux 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 a normal
   GNU/Linux "finalizer" file, `crtn.o'.  */

#undef  ENDFILE_SPEC
#define ENDFILE_SPEC \
  "%{!shared:crtend.o%s} %{shared:crtendS.o%s} crtn.o%s"

#undef  LINK_SPEC
#define LINK_SPEC "%{h*} %{version:-v} \
   %{b} %{Wl,*:%*} \
   %{static:-Bstatic} \
   %{shared:-shared} \
   %{symbolic:-Bsymbolic} \
   %{rdynamic:-export-dynamic} \
   %{!dynamic-linker:-dynamic-linker /lib/ld-linux.so.2} \
   -X \
   %{mbig-endian:-EB}" \
   SUBTARGET_EXTRA_LINK_SPEC

#define TARGET_OS_CPP_BUILTINS()		\
    do {					\
	builtin_define_std ("unix");		\
	builtin_define_std ("linux");		\
	builtin_define ("__gnu_linux__");	\
	builtin_define ("__ELF__");		\
	builtin_assert ("system=unix");		\
	builtin_assert ("system=posix");	\
    } while (0)

/* This is how we tell the assembler that two symbols have the same value.  */
#define ASM_OUTPUT_DEF(FILE, NAME1, NAME2) \
  do					   \
    {					   \
      assemble_name (FILE, NAME1); 	   \
      fputs (" = ", FILE);		   \
      assemble_name (FILE, NAME2);	   \
      fputc ('\n', FILE);		   \
    }					   \
  while (0)

/* NWFPE always understands FPA instructions.  */
#undef  FP_DEFAULT
#define FP_DEFAULT FP_SOFT3

/* Call the function profiler with a given profile label.  */
#undef  ARM_FUNCTION_PROFILER
#define ARM_FUNCTION_PROFILER(STREAM, LABELNO)  			\
{									\
  fprintf (STREAM, "\tbl\tmcount%s\n", NEED_PLT_RELOC ? "(PLT)" : "");	\
}

#undef  CC1_SPEC
#define CC1_SPEC "%{profile:-p}"

#define LINK_GCC_C_SEQUENCE_SPEC \
  "%{static:--start-group} %G %L %{static:--end-group}%{!static:%G}"