digest: fix aliasing bug with gcc 11

gcc 11 with -O2 optimizes away the store of the bit length into the
last 8 bytes of the context buffer due to an aliasing violation
(stored through uint64_t, retrieved through uint32_t).

To fix this, import the NetBSD patch from christos[0] which makes
it use memcpy instead.

[0] http://cvsweb.netbsd.org/bsdweb.cgi/src/common/lib/libc/hash/sha2/sha2.c.diff?r1=1.12&r2=1.13

pkgtools/digest/files/configure

@@ -580,8 +580,8 @@ MAKEFLAGS=
 # Identity of this package.
 PACKAGE_NAME='nbsd-digest'
 PACKAGE_TARNAME='nbsd-digest'
-PACKAGE_VERSION='20211023'
-PACKAGE_STRING='nbsd-digest 20190127'
+PACKAGE_VERSION='20220214'
+PACKAGE_STRING='nbsd-digest 20220214'
 PACKAGE_BUGREPORT='[email protected]'
 PACKAGE_URL=''
 

pkgtools/digest/files/sha2.c

@@ -548,7 +548,8 @@ void SHA256_Final(sha2_byte digest[], SHA256_CTX* context) {
 			*context->buffer = 0x80;
 		}
 		/* Set the bit count: */
-		*(sha2_word64*)&context->buffer[SHA256_SHORT_BLOCK_LENGTH] = context->bitcount;
+		MEMCPY_BCOPY(&context->buffer[SHA256_SHORT_BLOCK_LENGTH],
+		    &context->bitcount, sizeof(context->bitcount));
 
 		/* Final transform: */
 		SHA256_Transform(context, (sha2_word32*)context->buffer);