diff --git a/Makefile b/Makefile
index 0a3a396..96d581f 100644
--- a/Makefile
+++ b/Makefile
@@ -1,5 +1,5 @@
 CC=gcc
-LDFLAGS=`sdl-config --libs`
+LDFLAGS=`sdl-config --libs` -lm
 CFLAGS=-O3 -Wall -g `sdl-config --cflags`
 
 all: cscape maptest