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=${PROG_LD}
  11 AC_PROG_LD_GNU
  12 LD=""
  13
  14 AC_SUBST(BLDSHARED)
  15 AC_SUBST(LD)
  16 AC_SUBST(LDFLAGS)
  17
  18 # Assume non-shared by default and override below
  19 # these are the defaults, good for lots of systems
  20 BLDSHARED="false"
  21 LD="${CC}"
  22 PICFLAG=""
  23
  24 # allow for --with-hostld=gcc
  25 AC_ARG_WITH(hostld,[  --with-hostld=linker    choose host linker],
  26 [HOSTLD=$withval],
  27 [HOSTLD=$HOSTCC])
  28
  29 AC_MSG_CHECKING([whether to try to build shared libraries on $host_os])
  30
  31 # and these are for particular systems
  32 case "$host_os" in
  33         *linux*)
  34                 BLDSHARED="true"
  35                 LDFLAGS="$LDFLAGS -Wl,--export-dynamic"
  36                 ;;
  37         *solaris*)
  38                 BLDSHARED="true"
  39                 if test "${GCC}" = "yes"; then
  40                         if test "${ac_cv_prog_gnu_ld}" = "yes"; then
  41                                 LDFLAGS="$LDFLAGS -Wl,-E"
  42                         fi
  43                 fi
  44                 ;;
  45         *sunos*)
  46                 BLDSHARED="true"
  47                 ;;
  48         *netbsd* | *freebsd* | *dragonfly* )
  49                 BLDSHARED="true"
  50                 LDFLAGS="$LDFLAGS -Wl,--export-dynamic"
  51                 ;;
  52         *openbsd*)
  53                 BLDSHARED="true"
  54                 LDFLAGS="$LDFLAGS -Wl,-Bdynamic"
  55                 ;;
  56         *irix*)
  57                 BLDSHARED="true"
  58                 ;;
  59         *aix*)
  60                 BLDSHARED="true"
  61                 LDFLAGS="$LDFLAGS -Wl,-brtl,-bexpall,-bbigtoc"
  62                 ;;
  63         *hpux*)
  64                 # Use special PIC flags for the native HP-UX compiler.
  65                 BLDSHARED="true" # I hope this is correct
  66                 if test "$host_cpu" = "ia64"; then
  67                         LDFLAGS="$LDFLAGS -Wl,-E,+b/usr/local/lib/hpux32:/usr/lib/hpux32"
  68                 else
  69                         LDFLAGS="$LDFLAGS -Wl,-E,+b/usr/local/lib:/usr/lib"
  70                 fi
  71                 ;;
  72         *osf*)
  73                 BLDSHARED="true"
  74                 ;;
  75         *unixware*)
  76                 BLDSHARED="true"
  77                 ;;
  78         *darwin*)
  79                 BLDSHARED="true"
  80                 ;;
  81 esac
  82
  83 AC_MSG_RESULT($BLDSHARED)
  84
  85 AC_MSG_CHECKING([LD])
  86 AC_MSG_RESULT([$LD])
  87 AC_MSG_CHECKING([LDFLAGS])
  88 AC_MSG_RESULT([$LDFLAGS])
  89
  90 AC_SUBST(HOSTLD)
  91
  92 AC_LIBREPLACE_STLD
  93 AC_LIBREPLACE_STLD_FLAGS
  94
  95 AC_MSG_CHECKING([STLD])
  96 AC_MSG_RESULT([$STLD])
  97 AC_MSG_CHECKING([STLD_FLAGS])
  98 AC_MSG_RESULT([$STLD_FLAGS])
  99
 100 AC_LD_PICFLAG
 101 AC_LD_EXPORT_DYNAMIC
 102 AC_LD_SHLIBEXT
 103 AC_LD_SONAMEFLAG
 104 AC_LIBREPLACE_SHLD
 105 AC_LIBREPLACE_SHLD_FLAGS
 106 AC_LIBREPLACE_MDLD
 107 AC_LIBREPLACE_MDLD_FLAGS
 108 AC_LIBREPLACE_RUNTIME_LIB_PATH_VAR
 109
 110 #######################################################
 111 # test whether building a shared library actually works
 112 if test $BLDSHARED = true; then
 113
 114         AC_MSG_CHECKING([SHLD])
 115         AC_MSG_RESULT([$SHLD])
 116         AC_MSG_CHECKING([SHLD_FLAGS])
 117         AC_MSG_RESULT([$SHLD_FLAGS])
 118
 119         AC_MSG_CHECKING([MDLD])
 120         AC_MSG_RESULT([$MDLD])
 121         AC_MSG_CHECKING([MDLD_FLAGS])
 122         AC_MSG_RESULT([$MDLD_FLAGS])
 123
 124         AC_MSG_CHECKING([SHLIBEXT])
 125         AC_MSG_RESULT([$SHLIBEXT])
 126         AC_MSG_CHECKING([SONAMEFLAG])
 127         AC_MSG_RESULT([$SONAMEFLAG])
 128
 129         AC_MSG_CHECKING([PICFLAG])
 130         AC_MSG_RESULT([$PICFLAG])
 131
 132         AC_CACHE_CHECK([whether building shared libraries actually works],
 133                        [ac_cv_shlib_works],[
 134                         ac_cv_shlib_works=no
 135                         # try building a trivial shared library
 136                         # TODO: also test SONAMEFLAG
 137                         ${CC} ${CFLAGS} ${PICFLAG} -c ${srcdir-.}/build/tests/shlib.c -o shlib.o &&
 138                                 ${SHLD} ${SHLD_FLAGS} -o shlib.${SHLIBEXT} shlib.o &&
 139                                 ac_cv_shlib_works=yes
 140                         rm -f shlib.${SHLIBEXT} shlib.o
 141         ])
 142         AC_CACHE_CHECK([whether building shared modules actually works],
 143                        [ac_cv_shmod_works],[
 144                         ac_cv_shmod_works=no
 145                         # try building a trivial shared library
 146                         ${CC} ${CFLAGS} ${PICFLAG} -c ${srcdir-.}/build/tests/shlib.c -o shlib.o &&
 147                                 ${MDLD} ${MDLD_FLAGS} -o shlib.${SHLIBEXT} shlib.o &&
 148                                 ac_cv_shmod_works=yes
 149                         rm -f shlib.${SHLIBEXT} shlib.o
 150         ])
 151         if test $ac_cv_shlib_works = no -o $ac_cv_shmod_works = no; then
 152                 BLDSHARED=false
 153         fi
 154 fi
 155
 156 if test $BLDSHARED != true; then
 157         SHLD="shared-libraries-disabled"
 158         SHLD_FLAGS="shared-libraries-disabled"
 159         MDLD="shared-modules-disabled"
 160         MDLD_FLAGS="shared-modules-disabled"
 161         SHLIBEXT="shared_libraries_disabled"
 162         SONAMEFLAG="shared-libraries-disabled"
 163         PICFLAG=""
 164         AC_MSG_CHECKING([SHLD])
 165         AC_MSG_RESULT([$SHLD])
 166         AC_MSG_CHECKING([SHLD_FLAGS])
 167         AC_MSG_RESULT([$SHLD_FLAGS])
 168
 169         AC_MSG_CHECKING([MDLD])
 170         AC_MSG_RESULT([$MDLD])
 171         AC_MSG_CHECKING([MDLD_FLAGS])
 172         AC_MSG_RESULT([$MDLD_FLAGS])
 173
 174         AC_MSG_CHECKING([SHLIBEXT])
 175         AC_MSG_RESULT([$SHLIBEXT])
 176         AC_MSG_CHECKING([SONAMEFLAG])
 177         AC_MSG_RESULT([$SONAMEFLAG])
 178
 179         AC_MSG_CHECKING([PICFLAG])
 180         AC_MSG_RESULT([$PICFLAG])
 181 fi
 182
 183 AC_DEFINE_UNQUOTED(SHLIBEXT, "$SHLIBEXT", [Shared library extension])
 184
 185 AC_MSG_CHECKING([if we can link using the selected flags])
 186 AC_TRY_RUN([#include "${srcdir-.}/build/tests/trivial.c"],
 187             AC_MSG_RESULT(yes),
 188             AC_MSG_ERROR([we cannot link with the selected cc and ld flags. Aborting configure]),
 189             AC_MSG_WARN([cannot run when cross-compiling]))
 190
 191
 192 USESHARED=false
 193 AC_SUBST(USESHARED)
 194
 195 AC_ARG_ENABLE(dso,
 196 [  --enable-dso                   Enable using shared libraries internally (experimental)],
 197 [],[enable_dso=no])
 198
 199 if test x"$enable_dso" = x"yes" -a x"$BLDSHARED" != x"true"; then
 200         AC_MSG_ERROR([--enable-dso: no support for shared libraries])
 201 fi
 202
 203 if test x"$enable_dso" != x"no"; then
 204         USESHARED=$BLDSHARED
 205 fi
 206
 207 AC_MSG_CHECKING([if binaries will use shared libraries])
 208 AC_MSG_RESULT([$USESHARED])