Silence some valgrind warnings.

The ignored field is never used, so it doesn't matter that the
comparison to the old value is reading uninitialised memory (unless the
compiler is clever enough to spot that this is undefined behaviour and
do something evil).

encoding2.c

@@ -236,7 +236,7 @@ static const char *sizeof_type(const char *type, size_t *size)
 		{
 			// All pointers look the same to me.
 			*size += sizeof(void*) * 8;
-			size_t ignored;
+			size_t ignored = 0;
 			// Skip the definition of the pointeee type.
 			return sizeof_type(type+1, &ignored);
 		}
@@ -329,7 +329,7 @@ static const char *alignof_type(const char *type, size_t *align)
 		{
 			*align = max((alignof(void*) * 8), *align);
 			// All pointers look the same to me.
-			size_t ignored;
+			size_t ignored = 0;
 			// Skip the definition of the pointeee type.
 			return alignof_type(type+1, &ignored);
 		}