diff --git a/tests/scripts/all.sh b/tests/scripts/all.sh
index 23615f2..369eb24 100755
--- a/tests/scripts/all.sh
+++ b/tests/scripts/all.sh
@@ -3540,7 +3540,7 @@
     make clean
     make test programs/test/selftest CC=gcc CFLAGS='-O2 -Werror'
     # check that there is no AESNI code present
-    ./programs/test/selftest | grep -q "AESNI code" && false "AESNI code built when MBEDTLS_AESNI_C unset"
+    ./programs/test/selftest | grep -qv "AESNI code" || false "AESNI code built when MBEDTLS_AESNI_C unset"
 }
 
 component_test_aes_only_128_bit_keys () {