--- a/Makefile.inc
+++ b/Makefile.inc
@@ -559,7 +559,7 @@ LDFLAGS_PTHREAD = $(if $(MACOS),,-pthread)
 
 # External libraries
 
-LDLIBS += -lpthread $(if $(MACOS)$(OPENBSD),,-lrt) -lm
+LDLIBS += -lc++_shared -lm
 
 # Global compilation flags.
 # Additional flags can be passed on the "make" command line using xxFLAGS_EXTRA.