Merge #1639: Make static context const

432ac57 Make static context const (Daniel Pfeifer)

Pull request description:

  Fixes #1637

ACKs for top commit:
  real-or-random:
    ACK 432ac57

Tree-SHA512: 64e91a02fff8fd31bd6da3a37f25f572877343fb8081693c42a0517fae5cbc3951f38ec372d0a1fd91388596b6d85531d3f154a49208b43b0f56a4c72951c42b

Author: real-or-random

include/secp256k1.h

@@ -230,10 +230,10 @@ typedef int (*secp256k1_nonce_function)(
  *
  *  It is highly recommended to call secp256k1_selftest before using this context.
  */
-SECP256K1_API const secp256k1_context *secp256k1_context_static;
+SECP256K1_API const secp256k1_context * const secp256k1_context_static;
 
 /** Deprecated alias for secp256k1_context_static. */
-SECP256K1_API const secp256k1_context *secp256k1_context_no_precomp
+SECP256K1_API const secp256k1_context * const secp256k1_context_no_precomp
 SECP256K1_DEPRECATED("Use secp256k1_context_static instead");
 
 /** Perform basic self tests (to be used in conjunction with secp256k1_context_static)

src/secp256k1.c

@@ -71,8 +71,8 @@ static const secp256k1_context secp256k1_context_static_ = {
     { secp256k1_default_error_callback_fn, 0 },
     0
 };
-const secp256k1_context *secp256k1_context_static = &secp256k1_context_static_;
-const secp256k1_context *secp256k1_context_no_precomp = &secp256k1_context_static_;
+const secp256k1_context * const secp256k1_context_static = &secp256k1_context_static_;
+const secp256k1_context * const secp256k1_context_no_precomp = &secp256k1_context_static_;
 
 /* Helper function that determines if a context is proper, i.e., is not the static context or a copy thereof.
  *