source4/build/m4/check_ld.m4

   1 dnl SMB Build Environment LD Checks
   2 dnl -------------------------------------------------------
   3 dnl  Copyright (C) Stefan (metze) Metzmacher 2004
   4 dnl  Copyright (C) Jelmer Vernooij 2006
   5 dnl  Released under the GNU GPL
   6 dnl -------------------------------------------------------
   7 dnl
   8
   9 AC_PATH_PROG(PROG_LD,ld)
  10 LD=${PROG_LD}
  11 AC_PROG_LD_GNU
  12 LD=""
  13 AC_PATH_PROG(PROG_AR, ar)
  14
  15 AC_SUBST(STLD)
  16 AC_SUBST(STLD_FLAGS)
  17 AC_SUBST(BLDSHARED)
  18 AC_SUBST(LD)
  19 AC_SUBST(LDFLAGS)
  20 AC_SUBST(SHLD)
  21 AC_SUBST(SHLD_FLAGS)
  22 AC_SUBST(SHLIBEXT)
  23 AC_SUBST(SONAMEFLAG)
  24 AC_SUBST(PICFLAG)
  25
  26 # Assume non-shared by default and override below
  27 # these are the defaults, good for lots of systems
  28 STLD=${PROG_AR}
  29 STLD_FLAGS="-rcs"
  30 BLDSHARED="false"
  31 LD="${CC}"
  32 LDFLAGS=""
  33 SHLD="${CC}"
  34 SHLD_FLAGS="-shared"
  35 SHLIBEXT="so"
  36 SONAMEFLAG=""
  37 PICFLAG=""
  38
  39 AC_MSG_CHECKING([ability to build shared libraries])
  40
  41 # and these are for particular systems
  42 case "$host_os" in
  43         *linux*)
  44                 BLDSHARED="true"
  45                 if test "${ac_cv_gnu_ld_no_default_allow_shlib_undefined}" = "yes"; then
  46                         SHLD_FLAGS="-shared -Wl,-Bsymbolic -Wl,--allow-shlib-undefined"
  47                 else
  48                         SHLD_FLAGS="-shared -Wl,-Bsymbolic"
  49                 fi
  50                 LDFLAGS="-Wl,--export-dynamic"
  51                 PICFLAG="-fPIC"
  52                 SONAMEFLAG="-Wl,-soname="
  53                 ;;
  54         *solaris*)
  55                 BLDSHARED="true"
  56                 SHLD_FLAGS="-G"
  57                 SONAMEFLAG="-h "
  58                 if test "${GCC}" = "yes"; then
  59                         PICFLAG="-fPIC"
  60                         SONAMEFLAG="-Wl,-soname="
  61                         if test "${ac_cv_prog_gnu_ld}" = "yes"; then
  62                                 LDFLAGS="-Wl,-E"
  63                         fi
  64                 else
  65                         PICFLAG="-KPIC"
  66                         ## ${CFLAGS} added for building 64-bit shared
  67                         ## libs using Sun's Compiler
  68                         SHLD_FLAGS="-G \${CFLAGS}"
  69                 fi
  70                 ;;
  71         *sunos*)
  72                 BLDSHARED="true"
  73                 SHLD_FLAGS="-G"
  74                 SONAMEFLAG="-Wl,-h,"
  75                 PICFLAG="-KPIC"   # Is this correct for SunOS
  76                 ;;
  77         *netbsd* | *freebsd* | *dragonfly* )
  78                 BLDSHARED="true"
  79                 LDFLAGS="-Wl,--export-dynamic"
  80                 SONAMEFLAG="-Wl,-soname,"
  81                 PICFLAG="-fPIC -DPIC"
  82                 ;;
  83         *openbsd*)
  84                 BLDSHARED="true"
  85                 LDFLAGS="-Wl,-Bdynamic"
  86                 SONAMEFLAG="-Wl,-soname,"
  87                 PICFLAG="-fPIC"
  88                 ;;
  89         *irix*)
  90                 BLDSHARED="true"
  91                 SHLD_FLAGS="-set_version sgi1.0 -shared"
  92                 SONAMEFLAG="-soname "
  93                 SHLD="${PROG_LD}"
  94                 if test "${GCC}" = "yes"; then
  95                         PICFLAG="-fPIC"
  96                 else
  97                         PICFLAG="-KPIC"
  98                 fi
  99                 ;;
 100         *aix*)
 101                 BLDSHARED="true"
 102                 SHLD_FLAGS="-Wl,-G,-bexpall"
 103                 LDFLAGS="-Wl,-brtl,-bexpall,-bbigtoc"
 104                 # as AIX code is always position independent...
 105                 PICFLAG="-O2"
 106                 ;;
 107         *hpux*)
 108                 # Use special PIC flags for the native HP-UX compiler.
 109                 if test $ac_cv_prog_cc_Ae = yes; then
 110                         BLDSHARED="true"
 111                         SHLD_FLAGS="-b -Wl,-B,symbolic,-b,-z"
 112                         SONAMEFLAG="-Wl,+h "
 113                         PICFLAG="+z"
 114                 elif test "${GCC}" = "yes"; then
 115                         BLDSHARED="true" # I hope this is correct
 116                         PICFLAG="-fPIC"
 117                 fi
 118                 if test "$host_cpu" = "ia64"; then
 119                         SHLIBEXT="so"
 120                         LDFLAGS="-Wl,-E,+b/usr/local/lib/hpux32:/usr/lib/hpux32"
 121                 else
 122                         SHLIBEXT="sl"
 123                         LDFLAGS="-Wl,-E,+b/usr/local/lib:/usr/lib"
 124                 fi
 125                 ;;
 126         *osf*)
 127                 BLDSHARED="true"
 128                 SONAMEFLAG="-Wl,-soname,"
 129                 PICFLAG="-fPIC"
 130                 ;;
 131         *unixware*)
 132                 BLDSHARED="true"
 133                 SONAMEFLAG="-Wl,-soname,"
 134                 PICFLAG="-KPIC"
 135                 ;;
 136         *darwin*)
 137                 BLDSHARED="true"
 138                 SHLD_FLAGS="-bundle -flat_namespace -undefined suppress"
 139                 SHLIBEXT="dylib"
 140                 ;;
 141 esac
 142
 143 AC_MSG_RESULT($BLDSHARED)
 144
 145 AC_MSG_CHECKING([LD])
 146 AC_MSG_RESULT([$LD])
 147 AC_MSG_CHECKING([LDFLAGS])
 148 AC_MSG_RESULT([$LDFLAGS])
 149
 150 AC_MSG_CHECKING([STLD])
 151 AC_MSG_RESULT([$STLD])
 152 AC_MSG_CHECKING([STLD_FLAGS])
 153 AC_MSG_RESULT([$STLD_FLAGS])
 154
 155 #######################################################
 156 # test whether building a shared library actually works
 157 if test $BLDSHARED = true; then
 158
 159 AC_MSG_CHECKING([SHLD])
 160 AC_MSG_RESULT([$SHLD])
 161 AC_MSG_CHECKING([SHLD_FLAGS])
 162 AC_MSG_RESULT([$SHLD_FLAGS])
 163
 164 AC_MSG_CHECKING([SHLIBEXT])
 165 AC_MSG_RESULT([$SHLIBEXT])
 166 AC_MSG_CHECKING([SONAMEFLAG])
 167 AC_MSG_RESULT([$SONAMEFLAG])
 168
 169 AC_MSG_CHECKING([PICFLAG])
 170 AC_MSG_RESULT([$PICFLAG])
 171
 172 AC_CACHE_CHECK([whether building shared libraries actually works],
 173                [ac_cv_shlib_works],[
 174    ac_cv_shlib_works=no
 175    # try building a trivial shared library
 176    ${CC} ${CFLAGS} ${PICFLAG} -c ${srcdir-.}/build/tests/shlib.c -o shlib.o &&
 177        ${SHLD} `eval echo ${SHLD_FLAGS} ` -o shlib.${SHLIBEXT} shlib.o &&
 178        ac_cv_shlib_works=yes
 179    rm -f shlib.${SHLIBEXT} shlib.o
 180 ])
 181 if test $ac_cv_shlib_works = no; then
 182    BLDSHARED=false
 183 fi
 184 fi
 185
 186 AC_ARG_ENABLE(dso,
 187 [  --enable-dso                 Enable building internal libraries as DSO's (experimental)],
 188 [ if test x$enable_dso != xyes; then
 189         BLDSHARED=false
 190   fi],
 191 [BLDSHARED=false])