There was a need to support thread ID types that couldn't be reliably cast

to 'unsigned long' (ie. odd platforms/compilers), so a pointer-typed
version was added but it required portable code to check *both* modes to
determine equality. This commit maintains the availability of both thread
ID types, but deprecates the type-specific accessor APIs that invoke the
callbacks - instead a single type-independent API is used.  This simplifies
software that calls into this interface, and should also make it less
error-prone - as forgetting to call and compare *both* thread ID accessors
could have led to hard-to-debug/infrequent bugs (that might only affect
certain platforms or thread implementations). As the CHANGES note says,
there were corresponding deprecations and replacements in the
thread-related functions for BN_BLINDING and ERR too.

crypto/ecdsa/ecdsatest.c

@@ -490,7 +490,7 @@ err:
 	if (ret)
 		ERR_print_errors(out);
 	CRYPTO_cleanup_all_ex_data();
-	ERR_remove_state(0);
+	ERR_remove_thread_state(NULL);
 	ERR_free_strings();
 	CRYPTO_mem_leaks(out);
 	if (out != NULL)