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