diff --git a/include/cjose/jwk.h b/include/cjose/jwk.h
index 8151174..966b99e 100644
--- a/include/cjose/jwk.h
+++ b/include/cjose/jwk.h
@@ -282,7 +282,7 @@ cjose_jwk_t *cjose_jwk_create_EC_spec(const cjose_jwk_ec_keyspec *spec, cjose_er
  *        information in the event of an error.
  * \returns The curve type
  */
-const cjose_jwk_ec_curve cjose_jwk_EC_get_curve(const cjose_jwk_t *jwk, cjose_err *err);
+cjose_jwk_ec_curve cjose_jwk_EC_get_curve(const cjose_jwk_t *jwk, cjose_err *err);
 
 /**
  * Creates a new symmetric octet JWK, using a secure random number generator.
diff --git a/src/concatkdf.c b/src/concatkdf.c
index f041b98..b55975f 100644
--- a/src/concatkdf.c
+++ b/src/concatkdf.c
@@ -12,19 +12,12 @@
 #include <malloc.h>
 #else
 #include <arpa/inet.h>
-#include <alloca.h>
 #endif
 #include <openssl/evp.h>
 #include <string.h>
 #include <cjose/base64.h>
 #include <cjose/util.h>
 
-#ifdef _WIN32
-#define STACK_ALLOC _alloca
-#else
-#define STACK_ALLOC alloca
-#endif
-
 ////////////////////////////////////////////////////////////////////////////////
 static uint8_t *_apply_uint32(const uint32_t value, uint8_t *buffer)
 {
diff --git a/src/jwk.c b/src/jwk.c
index 9b1606e..8dbdeec 100644
--- a/src/jwk.c
+++ b/src/jwk.c
@@ -1002,7 +1002,7 @@ cjose_jwk_t *cjose_jwk_create_EC_spec(const cjose_jwk_ec_keyspec *spec, cjose_er
     return jwk;
 }
 
-const cjose_jwk_ec_curve cjose_jwk_EC_get_curve(const cjose_jwk_t *jwk, cjose_err *err)
+cjose_jwk_ec_curve cjose_jwk_EC_get_curve(const cjose_jwk_t *jwk, cjose_err *err)
 {
     if (NULL == jwk || CJOSE_JWK_KTY_EC != cjose_jwk_get_kty(jwk, err))
     {