gcc/config/linux.h

   1 /* Definitions for systems using the Linux kernel, with or without
   2    MMU, using ELF at the compiler level but possibly FLT for final
   3    linked executables and shared libraries in some no-MMU cases, and
   4    possibly with a choice of libc implementations.
   5    Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2003, 2004, 2005, 2006,
   6    2007, 2009, 2010, 2011 Free Software Foundation, Inc.
   7    Contributed by Eric Youngdale.
   8    Modified for stabs-in-ELF by H.J. Lu (hjl@lucon.org).
   9
  10 This file is part of GCC.
  11
  12 GCC is free software; you can redistribute it and/or modify
  13 it under the terms of the GNU General Public License as published by
  14 the Free Software Foundation; either version 3, or (at your option)
  15 any later version.
  16
  17 GCC is distributed in the hope that it will be useful,
  18 but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 GNU General Public License for more details.
  21
  22 Under Section 7 of GPL version 3, you are granted additional
  23 permissions described in the GCC Runtime Library Exception, version
  24 3.1, as published by the Free Software Foundation.
  25
  26 You should have received a copy of the GNU General Public License and
  27 a copy of the GCC Runtime Library Exception along with this program;
  28 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  29 <http://www.gnu.org/licenses/>.  */
  30
  31 /* C libraries supported on Linux.  */
  32 #ifdef SINGLE_LIBC
  33 #define OPTION_GLIBC  (DEFAULT_LIBC == LIBC_GLIBC)
  34 #define OPTION_UCLIBC (DEFAULT_LIBC == LIBC_UCLIBC)
  35 #define OPTION_BIONIC (DEFAULT_LIBC == LIBC_BIONIC)
  36 #else
  37 #define OPTION_GLIBC  (linux_libc == LIBC_GLIBC)
  38 #define OPTION_UCLIBC (linux_libc == LIBC_UCLIBC)
  39 #define OPTION_BIONIC (linux_libc == LIBC_BIONIC)
  40 #endif
  41
  42 #define LINUX_TARGET_OS_CPP_BUILTINS()                          \
  43     do {                                                        \
  44         if (OPTION_GLIBC)                                       \
  45           builtin_define ("__gnu_linux__");                     \
  46         builtin_define_std ("linux");                           \
  47         builtin_define_std ("unix");                            \
  48         builtin_assert ("system=linux");                        \
  49         builtin_assert ("system=unix");                         \
  50         builtin_assert ("system=posix");                        \
  51     } while (0)
  52
  53 /* Determine which dynamic linker to use depending on whether GLIBC or
  54    uClibc or Bionic is the default C library and whether
  55    -muclibc or -mglibc or -mbionic has been passed to change the default.  */
  56
  57 #define CHOOSE_DYNAMIC_LINKER1(LIBC1, LIBC2, LIBC3, LD1, LD2, LD3)      \
  58   "%{" LIBC2 ":" LD2 ";:%{" LIBC3 ":" LD3 ";:" LD1 "}}"
  59
  60 #if DEFAULT_LIBC == LIBC_GLIBC
  61 #define CHOOSE_DYNAMIC_LINKER(G, U, B) \
  62   CHOOSE_DYNAMIC_LINKER1 ("mglibc", "muclibc", "mbionic", G, U, B)
  63 #elif DEFAULT_LIBC == LIBC_UCLIBC
  64 #define CHOOSE_DYNAMIC_LINKER(G, U, B) \
  65   CHOOSE_DYNAMIC_LINKER1 ("muclibc", "mglibc", "mbionic", U, G, B)
  66 #elif DEFAULT_LIBC == LIBC_BIONIC
  67 #define CHOOSE_DYNAMIC_LINKER(G, U, B) \
  68   CHOOSE_DYNAMIC_LINKER1 ("mbionic", "mglibc", "muclibc", B, G, U)
  69 #else
  70 #error "Unsupported DEFAULT_LIBC"
  71 #endif /* DEFAULT_LIBC */
  72
  73 /* For most targets the following definitions suffice;
  74    GLIBC_DYNAMIC_LINKER must be defined for each target using them, or
  75    GLIBC_DYNAMIC_LINKER32 and GLIBC_DYNAMIC_LINKER64 for targets
  76    supporting both 32-bit and 64-bit compilation.  */
  77 #define UCLIBC_DYNAMIC_LINKER "/lib/ld-uClibc.so.0"
  78 #define UCLIBC_DYNAMIC_LINKER32 "/lib/ld-uClibc.so.0"
  79 #define UCLIBC_DYNAMIC_LINKER64 "/lib/ld64-uClibc.so.0"
  80 #define BIONIC_DYNAMIC_LINKER "/system/bin/linker"
  81 #define BIONIC_DYNAMIC_LINKER32 "/system/bin/linker"
  82 #define BIONIC_DYNAMIC_LINKER64 "/system/bin/linker64"
  83
  84 #define LINUX_DYNAMIC_LINKER                                            \
  85   CHOOSE_DYNAMIC_LINKER (GLIBC_DYNAMIC_LINKER, UCLIBC_DYNAMIC_LINKER,   \
  86                          BIONIC_DYNAMIC_LINKER)
  87 #define LINUX_DYNAMIC_LINKER32                                          \
  88   CHOOSE_DYNAMIC_LINKER (GLIBC_DYNAMIC_LINKER32, UCLIBC_DYNAMIC_LINKER32, \
  89                          BIONIC_DYNAMIC_LINKER32)
  90 #define LINUX_DYNAMIC_LINKER64                                          \
  91   CHOOSE_DYNAMIC_LINKER (GLIBC_DYNAMIC_LINKER64, UCLIBC_DYNAMIC_LINKER64, \
  92                          BIONIC_DYNAMIC_LINKER64)
  93
  94 /* Determine whether the entire c99 runtime
  95    is present in the runtime library.  */
  96 #define TARGET_C99_FUNCTIONS (OPTION_GLIBC)
  97
  98 /* Whether we have sincos that follows the GNU extension.  */
  99 #define TARGET_HAS_SINCOS (OPTION_GLIBC || OPTION_BIONIC)