diff --git a/include/option.sh b/include/option.sh
index 45b6f67..7348b76 100755
--- a/include/option.sh
+++ b/include/option.sh
@@ -15,13 +15,14 @@ tmpgit="${PWD}/tmp/gitclone"
 eval "$(setvars "" board boarddir)"
 
 threads=
-set | grep CBMK_THREADS 1>/dev/null 2>/dev/null || threads=$(nproc) || :
-[ -z "$threads" ] && threads=$CBMK_THREADS
-[ -z "$threads" ] && threads=1 # CBMK_THREADS not set, and nproc failed
+set | grep CBMK_THREADS 1>/dev/null 2>/dev/null && threads="$CBMK_THREADS"
+[ -z "$threads" ] && threads=1
 
 expr "X$threads" : "X-\{0,1\}[0123456789][0123456789]*$" \
     1>/dev/null 2>/dev/null || threads=1 # user specified a non-integer
 
+export CBMK_THREADS="$threads"
+
 items()
 {
 	rval=1