diff --git a/src/interface.c b/src/interface.c
index d36e79da..8968e668 100644
--- a/src/interface.c
+++ b/src/interface.c
@@ -165,7 +165,6 @@ static CK_RV p11prov_interface_init(P11PROV_MODULE *mctx)
         return CKR_HOST_MEMORY;
     }
 
-    ret = CKR_FUNCTION_NOT_SUPPORTED;
     intf->GetInterface = dlsym(mctx->dlhandle, "C_GetInterface");
     if (!intf->GetInterface) {
         char *err = dlerror();
diff --git a/src/objects.c b/src/objects.c
index ccfde31c..d91c292a 100644
--- a/src/objects.c
+++ b/src/objects.c
@@ -1870,7 +1870,6 @@ static int p11prov_obj_export_public_ec_key(P11PROV_OBJ *obj,
     switch (key_type) {
     case CKK_EC:
         attrs[0].type = CKA_P11PROV_CURVE_NID;
-        nattr = 1;
         rv = get_public_attrs(obj, attrs, 1);
         if (rv != CKR_OK) {
             P11PROV_raise(obj->ctx, rv, "Failed to get EC key curve nid");
diff --git a/src/signature.c b/src/signature.c
index f726a199..e3fa137c 100644
--- a/src/signature.c
+++ b/src/signature.c
@@ -877,7 +877,9 @@ static CK_RV p11prov_sig_operate(P11PROV_SIG_CTX *sigctx, unsigned char *sig,
         if (sigctx->operation == CKF_VERIFY) {
             return CKR_ARGUMENTS_BAD;
         }
-        return p11prov_sig_get_sig_size(sigctx, siglen);
+        if (siglen) {
+            return p11prov_sig_get_sig_size(sigctx, siglen);
+        }
     }
 
     if (sigctx->operation == CKF_SIGN && sigctx->mechtype == CKM_RSA_X_509) {
@@ -1042,9 +1044,11 @@ static int p11prov_sig_digest_final(P11PROV_SIG_CTX *sigctx, unsigned char *sig,
         if (sigctx->operation == CKF_VERIFY) {
             goto done;
         }
-        ret = p11prov_sig_get_sig_size(sigctx, siglen);
-        if (ret == CKR_OK) {
-            result = RET_OSSL_OK;
+        if (siglen) {
+            ret = p11prov_sig_get_sig_size(sigctx, siglen);
+            if (ret == CKR_OK) {
+                result = RET_OSSL_OK;
+            }
         }
         return result;
     }
@@ -1868,7 +1872,7 @@ static int p11prov_ecdsa_digest_sign_final(void *ctx, unsigned char *sig,
 {
     P11PROV_SIG_CTX *sigctx = (P11PROV_SIG_CTX *)ctx;
     unsigned char raw[P11PROV_MAX_RAW_ECC_SIG_SIZE];
-    size_t rawlen;
+    size_t rawlen = 0;
     int ret;
 
     /* the siglen might be uninitialized when called from openssl */