--- src/Makefile.in.orig
+++ src/Makefile.in
@@ -250,7 +250,7 @@
 
 liquidwar-mapgen: $(OBJ_FILES_MAPGEN)
 	@echo "Linking $@ (target=$(TARGET), debug=$(DEBUG), static=$(STATIC))"
-	@$(CC) $(LDFLAGS) $(LINK_OPTIONS) -o $@ $(OBJ_FILES_MAPGEN) $(PTHREAD) $(EXTERN_LIBS) 
+	@$(CC) $(LDFLAGS) $(LINK_OPTIONS) -o $@ $(OBJ_FILES_MAPGEN) $(PTHREAD) $(EXTERN_LIBS) -lm
 
 dep:
 	@find . \