config/picflag.m4

   1 # _GCC_PICFLAG(FLAG, DISPATCH)
   2 # ----------------------------
   3 # Store PIC flag corresponding to DISPATCH triplet in FLAG.
   4 # Explit use of -fpic in CFLAGS corresponding to FLAG overrides default.
   5 AC_DEFUN([_GCC_PICFLAG], [
   6
   7 case "${$2}" in
   8     # PIC is the default on some targets or must not be used.
   9     *-*-darwin*)
  10         # PIC is the default on this platform
  11         # Common symbols not allowed in MH_DYLIB files
  12         $1=-fno-common
  13         ;;
  14     alpha*-dec-osf5*)
  15         # PIC is the default.
  16         ;;
  17     hppa*64*-*-hpux*)
  18         # PIC is the default for 64-bit PA HP-UX.
  19         ;;
  20     i[[34567]]86-*-cygwin* | i[[34567]]86-*-mingw* | x86_64-*-mingw*)
  21         ;;
  22     i[[34567]]86-*-interix3*)
  23         # Interix 3.x gcc -fpic/-fPIC options generate broken code.
  24         # Instead, we relocate shared libraries at runtime.
  25         ;;
  26     i[[34567]]86-*-nto-qnx*)
  27         # QNX uses GNU C++, but need to define -shared option too, otherwise
  28         # it will coredump.
  29         $1='-fPIC -shared'
  30         ;;
  31     i[[34567]]86-pc-msdosdjgpp*)
  32         # DJGPP does not support shared libraries at all.
  33         ;;
  34     ia64*-*-hpux*)
  35         # On IA64 HP-UX, PIC is the default but the pic flag
  36         # sets the default TLS model and affects inlining.
  37         $1=-fPIC
  38         ;;
  39     mips-sgi-irix6*)
  40         # PIC is the default.
  41         ;;
  42     rs6000-ibm-aix* | powerpc-ibm-aix*)
  43         # All AIX code is PIC.
  44         ;;
  45
  46     # Some targets support both -fPIC and -fpic, but prefer the latter.
  47     # FIXME: Why?
  48     i[[34567]]86-*-* | x86_64-*-*)
  49         $1=-fpic
  50         ;;
  51     m68k-*-*)
  52         $1=-fpic
  53         ;;
  54     s390*-*-*)
  55         $1=-fpic
  56         ;;
  57     # FIXME: Override -fPIC default in libgcc only?
  58     sh-*-linux* | sh[[2346lbe]]*-*-linux*)
  59         $1=-fpic
  60         ;;
  61     # FIXME: Simplify to sh*-*-netbsd*?
  62     sh-*-netbsdelf* | shl*-*-netbsdelf* | sh5-*-netbsd* | sh5l*-*-netbsd* | \
  63       sh64-*-netbsd* | sh64l*-*-netbsd*)
  64         $1=-fpic
  65         ;;
  66     # Default to -fPIC unless specified otherwise.
  67     *)
  68         $1=-fPIC
  69         ;;
  70 esac
  71
  72 # If the user explicitly uses -fpic/-fPIC, keep that.
  73 case "${m4_bpatsubsts($1, PICFLAG, CFLAGS)}" in
  74     *-fpic*)
  75         $1=-fpic
  76         ;;
  77     *-fPIC*)
  78         $1=-fPIC
  79         ;;
  80 esac
  81 ])
  82
  83 # GCC_PICFLAG
  84 # -----------
  85 # Store host PIC flag in PICFLAG.
  86 AC_DEFUN([GCC_PICFLAG], [
  87   AC_REQUIRE([AC_CANONICAL_HOST])
  88   _GCC_PICFLAG([PICFLAG], [host])])
  89
  90 # GCC_PICFLAG_FOR_TARGET
  91 # ----------------------
  92 # Store target PIC flag in PICFLAG_FOR_TARGET.
  93 AC_DEFUN([GCC_PICFLAG_FOR_TARGET], [
  94   AC_REQUIRE([AC_CANONICAL_TARGET])
  95   _GCC_PICFLAG([PICFLAG_FOR_TARGET], [target])])