diff --git a/build.sh b/build.sh
index 8afadce..20bcf53 100755
--- a/build.sh
+++ b/build.sh
@@ -15,7 +15,7 @@ LDFLAGS='-lircclient -lsqlite3'
 mkdir -p $PREFIX && echo "Made directory: $PREFIX"
 
 # Bourne shell is evil
-if [ ${DEBUG} -eq 1 ]
+if [ ${DEBUG-0} -eq 1 ]
 then
   CFLAGS=`echo "${CFLAGS} -Og -g3"`
 else