diff --git a/src/glsl/glcpp/tests/glcpp-test b/src/glsl/glcpp/tests/glcpp-test
index 5dc08ea6acb..e8f3b546387 100755
--- a/src/glsl/glcpp/tests/glcpp-test
+++ b/src/glsl/glcpp/tests/glcpp-test
@@ -2,6 +2,34 @@
 
 trap 'rm $test.valgrind-errors; exit 1' INT QUIT
 
+usage ()
+{
+    cat <<EOF
+Usage: glcpp [options...]
+
+Run the test suite for mesa's GLSL pre-processor.
+
+Valid options include:
+
+	--valgrind	Run the test suite a second time under valgrind
+EOF
+}
+
+# Parse command-line options
+for option; do
+    if [ "${option}" = '--help' ] ; then
+	usage
+	exit 0
+    elif [ "${option}" = '--valgrind' ] ; then
+	do_valgrind=yes
+    else
+	echo "Unrecognized option: $option" >&2
+	echo >&2
+	usage
+	exit 1
+    fi
+done
+
 total=0
 pass=0
 clean=0
@@ -24,23 +52,25 @@ echo ""
 echo "$pass/$total tests returned correct results"
 echo ""
 
-echo "====== Testing for valgrind cleanliness ======"
-for test in *.c; do
-    echo -n "Testing $test with valgrind..."
-    valgrind --error-exitcode=31 --log-file=$test.valgrind-errors ../glcpp < $test >/dev/null 2>&1
-    if [ "$?" = "31" ]; then
-	echo "ERRORS"
-	cat $test.valgrind-errors
-    else
-	echo "CLEAN"
-	clean=$((clean+1))
-	rm $test.valgrind-errors
-    fi
-done
+if [ "$do_valgrind" = "yes" ]; then
+    echo "====== Testing for valgrind cleanliness ======"
+    for test in *.c; do
+	echo -n "Testing $test with valgrind..."
+	valgrind --error-exitcode=31 --log-file=$test.valgrind-errors ../glcpp < $test >/dev/null 2>&1
+	if [ "$?" = "31" ]; then
+	    echo "ERRORS"
+	    cat $test.valgrind-errors
+	else
+	    echo "CLEAN"
+	    clean=$((clean+1))
+	    rm $test.valgrind-errors
+	fi
+    done
 
-echo ""
-echo "$pass/$total tests returned correct results"
-echo "$clean/$total tests are valgrind-clean"
+    echo ""
+    echo "$pass/$total tests returned correct results"
+    echo "$clean/$total tests are valgrind-clean"
+fi
 
 if [ "$pass" = "$total" ] && [ "$clean" = "$total" ]; then
     exit 0