diff --git a/tools/setlocalversion b/tools/setlocalversion
index 9a23825..f6503fa 100755
--- a/tools/setlocalversion
+++ b/tools/setlocalversion
@@ -9,14 +9,18 @@ usage() {
 cd "${1:-.}" || usage
 
 # Check for git and a git repo.
-if head=`git rev-parse --verify HEAD 2>/dev/null`; then
-	# Do we have an untagged version?
-	if  [ "`git name-rev --tags HEAD`" = "HEAD undefined" ]; then
-		printf '%s%s' -g `echo "$head" | cut -c1-8`
-	fi
+if ( which git >& /dev/null ) && [ -d .git ]; then
+	if head=`git rev-parse --verify HEAD 2>/dev/null`; then
+		# Do we have an untagged version?
+		if  [ "`git name-rev --tags HEAD`" = "HEAD undefined" ]; then
+			printf '%s%s' -g `echo "$head" | cut -c1-8`
+		fi
 
-	# Are there uncommitted changes?
-	if git diff-files | read dummy; then
-		printf '%s' -dirty
+		# Are there uncommitted changes?
+		if git diff-files | read dummy; then
+			printf '%s' -dirty
+		fi
 	fi
+else
+	echo -n "-unknown"
 fi