Autodetect the availability of -export-dynamic in the linker.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66156 91177308-0d34-0410-b5e6-96231b3b80d8

autoconf/configure.ac

@@ -636,9 +636,12 @@ AC_PATH_PROGS(OCAMLDEP, [ocamldep])
 AC_PATH_PROGS(OCAMLDOC, [ocamldoc])
 AC_PATH_PROGS(GAS, [gas as])
 
-dnl Determine if the linker supports the -R option.
+dnl Determine whether the linker supports the -R option.
 AC_LINK_USE_R
 
+dnl Determine whether the linker supports the -export-dynamic option.
+AC_LINK_EXPORT_DYNAMIC
+
 dnl Check for libtool and the library that has dlopen function (which must come
 dnl before the AC_PROG_LIBTOOL check in order to enable dlopening libraries with
 dnl libtool).
@@ -1013,16 +1016,25 @@ if test "$binding_prereqs_failed" = 1 ; then
   AC_MSG_ERROR([Prequisites for bindings not satisfied. Fix them or use configure --disable-bindings.])
 fi
 
-dnl Determine if the compiler supports -fvisibility-inlines-hidden.
+dnl Determine whether the compiler supports -fvisibility-inlines-hidden.
 AC_CXX_USE_VISIBILITY_INLINES_HIDDEN
 
 dnl Determine linker rpath flag
-case $llvm_cv_os_type in
-  SunOS) RPATH="-Wl,-R" ;;
-  *) RPATH="-Wl,-rpath" ;;
-esac
+if test "$llvm_cv_link_use_r" = "yes" ; then
+  RPATH="-Wl,-R"
+else
+  RPATH="-Wl,-rpath"
+fi
 AC_SUBST(RPATH)
 
+dnl Determine linker rdynamic flag
+if test "$llvm_cv_link_use_export_dynamic" = "yes" ; then
+  RDYNAMIC="-Wl,-export-dynamic"
+else
+  RDYNAMIC=""
+fi
+AC_SUBST(RDYNAMIC)
+
 dnl===-----------------------------------------------------------------------===
 dnl===
 dnl=== SECTION 10: Specify the output files and generate it