Use -lm flag to link the math library

Artur Zakirov · Artur Zakirov · commit 84f8d3effae1 · 2016-10-25T12:10:30.000+03:00
diff --git a/Makefile b/Makefile
@@ -13,6 +13,8 @@ PGFILEDESC = "RUM index access method"
 
 REGRESS = rum ruminv timestamp orderby altorder
 
+LDFLAGS_SL += $(filter -lm, $(LIBS))
+
 ifdef USE_PGXS
 PG_CONFIG = pg_config
 PGXS := $(shell $(PG_CONFIG) --pgxs)
