gcc/config/linux.h

   1 /* Definitions for Linux-based GNU systems with ELF format
   2    Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2003, 2004, 2005, 2006,
   3    2007, 2009, 2010 Free Software Foundation, Inc.
   4    Contributed by Eric Youngdale.
   5    Modified for stabs-in-ELF by H.J. Lu (hjl@lucon.org).
   6
   7 This file is part of GCC.
   8
   9 GCC is free software; you can redistribute it and/or modify
  10 it under the terms of the GNU General Public License as published by
  11 the Free Software Foundation; either version 3, or (at your option)
  12 any later version.
  13
  14 GCC is distributed in the hope that it will be useful,
  15 but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 GNU General Public License for more details.
  18
  19 Under Section 7 of GPL version 3, you are granted additional
  20 permissions described in the GCC Runtime Library Exception, version
  21 3.1, as published by the Free Software Foundation.
  22
  23 You should have received a copy of the GNU General Public License and
  24 a copy of the GCC Runtime Library Exception along with this program;
  25 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  26 <http://www.gnu.org/licenses/>.  */
  27
  28 /* Don't assume anything about the header files.  */
  29 #define NO_IMPLICIT_EXTERN_C
  30
  31 #undef ASM_APP_ON
  32 #define ASM_APP_ON "#APP\n"
  33
  34 #undef ASM_APP_OFF
  35 #define ASM_APP_OFF "#NO_APP\n"
  36
  37 #undef MD_EXEC_PREFIX
  38 #undef MD_STARTFILE_PREFIX
  39
  40 /* Provide a STARTFILE_SPEC appropriate for GNU/Linux.  Here we add
  41    the GNU/Linux magical crtbegin.o file (see crtstuff.c) which
  42    provides part of the support for getting C++ file-scope static
  43    object constructed before entering `main'.  */
  44
  45 #if defined HAVE_LD_PIE
  46 #define LINUX_TARGET_STARTFILE_SPEC \
  47   "%{!shared: %{pg|p|profile:gcrt1.o%s;pie:Scrt1.o%s;:crt1.o%s}} \
  48    crti.o%s %{static:crtbeginT.o%s;shared|pie:crtbeginS.o%s;:crtbegin.o%s}"
  49 #else
  50 #define LINUX_TARGET_STARTFILE_SPEC \
  51   "%{!shared: %{pg|p|profile:gcrt1.o%s;:crt1.o%s}} \
  52    crti.o%s %{static:crtbeginT.o%s;shared|pie:crtbeginS.o%s;:crtbegin.o%s}"
  53 #endif
  54 #undef  STARTFILE_SPEC
  55 #define STARTFILE_SPEC LINUX_TARGET_STARTFILE_SPEC
  56
  57 /* Provide a ENDFILE_SPEC appropriate for GNU/Linux.  Here we tack on
  58    the GNU/Linux magical crtend.o file (see crtstuff.c) which
  59    provides part of the support for getting C++ file-scope static
  60    object constructed before entering `main', followed by a normal
  61    GNU/Linux "finalizer" file, `crtn.o'.  */
  62
  63 #define LINUX_TARGET_ENDFILE_SPEC \
  64   "%{shared|pie:crtendS.o%s;:crtend.o%s} crtn.o%s"
  65 #undef  ENDFILE_SPEC
  66 #define ENDFILE_SPEC LINUX_TARGET_ENDFILE_SPEC
  67
  68 /* This is for -profile to use -lc_p instead of -lc.  */
  69 #define LINUX_TARGET_CC1_SPEC "%{profile:-p}"
  70 #ifndef CC1_SPEC
  71 #define CC1_SPEC LINUX_TARGET_CC1_SPEC
  72 #endif
  73
  74 /* The GNU C++ standard library requires that these macros be defined.  */
  75 #undef CPLUSPLUS_CPP_SPEC
  76 #define CPLUSPLUS_CPP_SPEC "-D_GNU_SOURCE %(cpp)"
  77
  78 #define LINUX_TARGET_LIB_SPEC \
  79   "%{pthread:-lpthread} \
  80    %{shared:-lc} \
  81    %{!shared:%{mieee-fp:-lieee} %{profile:-lc_p}%{!profile:-lc}}"
  82 #undef  LIB_SPEC
  83 #define LIB_SPEC LINUX_TARGET_LIB_SPEC
  84
  85 /* C libraries supported on Linux.  */
  86 #define OPTION_GLIBC  (linux_libc == LIBC_GLIBC)
  87 #define OPTION_UCLIBC (linux_libc == LIBC_UCLIBC)
  88 #define OPTION_BIONIC (linux_libc == LIBC_BIONIC)
  89
  90 #define LINUX_TARGET_OS_CPP_BUILTINS()                          \
  91     do {                                                        \
  92         if (OPTION_GLIBC)                                       \
  93           builtin_define ("__gnu_linux__");                     \
  94         builtin_define_std ("linux");                           \
  95         builtin_define_std ("unix");                            \
  96         builtin_assert ("system=linux");                        \
  97         builtin_assert ("system=unix");                         \
  98         builtin_assert ("system=posix");                        \
  99     } while (0)
 100
 101 #if defined(HAVE_LD_EH_FRAME_HDR)
 102 #define LINK_EH_SPEC "%{!static:--eh-frame-hdr} "
 103 #endif
 104
 105 /* Define this so we can compile MS code for use with WINE.  */
 106 #define HANDLE_PRAGMA_PACK_PUSH_POP
 107
 108 #undef LINK_GCC_C_SEQUENCE_SPEC
 109 #define LINK_GCC_C_SEQUENCE_SPEC \
 110   "%{static:--start-group} %G %L %{static:--end-group}%{!static:%G}"
 111
 112 /* Use --as-needed -lgcc_s for eh support.  */
 113 #ifdef HAVE_LD_AS_NEEDED
 114 #define USE_LD_AS_NEEDED 1
 115 #endif
 116
 117 /* Determine which dynamic linker to use depending on whether GLIBC or
 118    uClibc or Bionic is the default C library and whether
 119    -muclibc or -mglibc or -mbionic has been passed to change the default.  */
 120
 121 #define CHOOSE_DYNAMIC_LINKER1(LIBC1, LIBC2, LIBC3, LD1, LD2, LD3)      \
 122   "%{" LIBC2 ":" LD2 ";:%{" LIBC3 ":" LD3 ";:" LD1 "}}"
 123
 124 #if DEFAULT_LIBC == LIBC_GLIBC
 125 #define CHOOSE_DYNAMIC_LINKER(G, U, B) \
 126   CHOOSE_DYNAMIC_LINKER1 ("mglibc", "muclibc", "mbionic", G, U, B)
 127 #elif DEFAULT_LIBC == LIBC_UCLIBC
 128 #define CHOOSE_DYNAMIC_LINKER(G, U, B) \
 129   CHOOSE_DYNAMIC_LINKER1 ("muclibc", "mglibc", "mbionic", U, G, B)
 130 #elif DEFAULT_LIBC == LIBC_BIONIC
 131 #define CHOOSE_DYNAMIC_LINKER(G, U, B) \
 132   CHOOSE_DYNAMIC_LINKER1 ("mbionic", "mglibc", "muclibc", B, G, U)
 133 #else
 134 #error "Unsupported DEFAULT_LIBC"
 135 #endif /* DEFAULT_LIBC */
 136
 137 /* For most targets the following definitions suffice;
 138    GLIBC_DYNAMIC_LINKER must be defined for each target using them, or
 139    GLIBC_DYNAMIC_LINKER32 and GLIBC_DYNAMIC_LINKER64 for targets
 140    supporting both 32-bit and 64-bit compilation.  */
 141 #define UCLIBC_DYNAMIC_LINKER "/lib/ld-uClibc.so.0"
 142 #define UCLIBC_DYNAMIC_LINKER32 "/lib/ld-uClibc.so.0"
 143 #define UCLIBC_DYNAMIC_LINKER64 "/lib/ld64-uClibc.so.0"
 144 #define BIONIC_DYNAMIC_LINKER "/system/bin/linker"
 145 #define BIONIC_DYNAMIC_LINKER32 "/system/bin/linker"
 146 #define BIONIC_DYNAMIC_LINKER64 "/system/bin/linker64"
 147
 148 #define LINUX_DYNAMIC_LINKER                                            \
 149   CHOOSE_DYNAMIC_LINKER (GLIBC_DYNAMIC_LINKER, UCLIBC_DYNAMIC_LINKER,   \
 150                          BIONIC_DYNAMIC_LINKER)
 151 #define LINUX_DYNAMIC_LINKER32                                          \
 152   CHOOSE_DYNAMIC_LINKER (GLIBC_DYNAMIC_LINKER32, UCLIBC_DYNAMIC_LINKER32, \
 153                          BIONIC_DYNAMIC_LINKER32)
 154 #define LINUX_DYNAMIC_LINKER64                                          \
 155   CHOOSE_DYNAMIC_LINKER (GLIBC_DYNAMIC_LINKER64, UCLIBC_DYNAMIC_LINKER64, \
 156                          BIONIC_DYNAMIC_LINKER64)
 157
 158 /* Determine whether the entire c99 runtime
 159    is present in the runtime library.  */
 160 #define TARGET_C99_FUNCTIONS (OPTION_GLIBC)
 161
 162 /* Whether we have sincos that follows the GNU extension.  */
 163 #define TARGET_HAS_SINCOS (OPTION_GLIBC || OPTION_BIONIC)
 164
 165 #define TARGET_POSIX_IO