Fix python plugin test for BSD family, dlopen(3) on those

systems is part of libc library and linking to nonexistent
libdl will fail.

Tested on FreeBSD 11-Current, Debian 8

diff --git a/configure.ac b/configure.ac
index d9e0732..056815a 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -1233,7 +1233,7 @@ AM_PATH_PYTHON([2.5], [
                if test x"$platform_win32" = xno; then
                        # libpython.so
                        PYTHON_SHARED_LIB="libpython${PYTHON_VERSION}.so"
-                       LIBS="-ldl"
+                       AC_CHECK_LIB(dl, dlopen, [LIBS="-ldl"])
                        AC_MSG_CHECKING([whether to dlopen $PYTHON_SHARED_LIB works])
                        AC_RUN_IFELSE(
                                [AC_LANG_PROGRAM(