Let configure perform linker test with --version-script if enabled

acinclude.m4

@@ -131,6 +131,21 @@ iconv_close(cd);
 ])
 
 
+dnl LIBISOFS_ASSERT_VERS_LIBS is by Thomas Schmitt, libburnia project
+dnl It tests whether -Wl,--version-script=... works with the compiler
+AC_DEFUN([LIBISOFS_ASSERT_VERS_LIBS],
+[
+    libburnia_save_LDFLAGS="$LDFLAGS"
+    LDFLAGS="$LDFLAGS -Wl,--version-script=libisofs/libisofs.ver"
+    AC_TRY_LINK([#include <stdio.h>], [printf("Hello\n");],
+                [vers_libs_test="yes"], [vers_libs_test="no"])
+    if test x$vers_libs_test = xno
+    then
+        LDFLAGS="$libburnia_save_LDFLAGS"
+    fi
+])
+
+
 dnl LIBBURNIA_SET_PKGCONFIG determines the install directory for the *.pc file.
 dnl Important: Must be performed _after_ TARGET_SHIZZLE
 dnl

configure.ac

@@ -218,8 +218,14 @@ AC_ARG_ENABLE(versioned-libs,
 [  --enable-versioned-libs Enable strict symbol encapsulation , default=yes],
                , enable_versioned_libs=yes)
 if test x$enable_versioned_libs = xyes; then
-    LDFLAGS="$LDFLAGS -Wl,--version-script=libisofs/libisofs.ver"
-    echo "enabled  strict symbol encapsulation"
+    vers_libs_test=no
+    LIBISOFS_ASSERT_VERS_LIBS
+    if test x$vers_libs_test = xno
+    then 
+        echo "disabled strict symbol encapsulation (test failed)"
+    else
+        echo "enabled  strict symbol encapsulation"
+    fi
 else
     echo "disabled strict symbol encapsulation"
 fi