Related to this, the blake2 function (declared as static inline) is not used, which makes the Solaris and compilers unhappy. Patch for reference:

--- a/Modules/_blake2/impl/blake2.h
+++ b/Modules/_blake2/impl/blake2.h
@@ -169,11 +169,6 @@
   BLAKE2_API int blake2sp( uint8_t *out, const void *in, const void *key, size_t outlen, size_t inlen, size_t keylen );
   BLAKE2_API int blake2bp( uint8_t *out, const void *in, const void *key, size_t outlen, size_t inlen, size_t keylen );

-  static inline int blake2( uint8_t *out, const void *in, const void *key, size_t outlen, size_t inlen, size_t keylen )
-  {
-    return blake2b( out, in, key, outlen, inlen, keylen );
-  }
-
 #if defined(__cplusplus)
 }
 #endif