Fix libdl detection on FreeBSD.

Refs #4977

components/demo/Makefile.am

@@ -6,7 +6,7 @@ pkglib_LTLIBRARIES = \
 BUILT_SOURCES = \
 	demo.th
 
-nodist_libdemo_SOURCES = $(BUILT_SOURCES)
+nodist_libdemo_la_SOURCES = $(BUILT_SOURCES)
 
 CLEANFILES = \
 	demo-type.cpp

configure.ac

@@ -112,6 +112,9 @@ AC_CHECK_LIB(ws2_32, getsockname)
 AC_CHECK_LIB(shlwapi, PathRemoveFileSpecA)
 AC_CHECK_FUNCS([backtrace_symbols execvpe pipe2 pthread_set_name_np pthread_setname_np])
 
+AC_CHECK_LIB(c, dlopen, LIBDL="", [AC_CHECK_LIB(dl, dlopen, LIBDL="-ldl")])
+AC_SUBST([LIBDL])
+
 AC_TRY_LINK([#include <openssl/evp.h>
 #include <openssl/bio.h>
 #include <openssl/comp.h>], [BIO_f_zlib();], ac_cv_lib_biozlib="yes")

lib/base/Makefile.am

@@ -142,7 +142,7 @@ libbase_la_LDFLAGS = \
 	@VERSION_INFO@
 
 libbase_la_LIBADD = \
-	-ldl \
+	$(LIBDL) \
 	$(OPENSSL_LIBS) \
 	$(BOOST_SIGNALS_LIB) \
 	$(BOOST_THREAD_LIB) \

lib/icinga/Makefile.am

@@ -20,7 +20,7 @@ BUILT_SOURCES = \
 	user.th \
 	usergroup.th
 
-nodist_libicinga_SOURCES = $(BUILT_SOURCES)
+nodist_libicinga_la_SOURCES = $(BUILT_SOURCES)
 
 CLEANFILES = \
 	icinga-type.cpp