diff --git a/tests/scripts/all-core.sh b/tests/scripts/all-core.sh
index 8377659..5a26224 100644
--- a/tests/scripts/all-core.sh
+++ b/tests/scripts/all-core.sh
@@ -171,6 +171,10 @@
             BUILTIN_SRC_PATH='tf-psa-crypto/drivers/builtin/src'
         else
             CRYPTO_CONFIG_H='include/psa/crypto_config.h'
+            # helper_armc6_build_test() relies on these being defined,
+            # but empty if the paths don't exits (as in 3.6).
+            PSA_CORE_PATH=''
+            BUILTIN_SRC_PATH=''
         fi
     else
         CONFIG_H='drivers/builtin/include/mbedtls/mbedtls_config.h'