static lzma_ret
block_encoder_init(lzma_coder *coder, lzma_allocator *allocator)
{
- // Prepare the Block options.
+ // Prepare the Block options. Even though Block encoder doesn't need
+ // compressed_size, uncompressed_size, and header_size to be
+ // initialized, it is a good idea to do it here, because this way
+ // we catch if someone gave us Filter ID that cannot be used in
+ // Blocks/Streams.
coder->block_options.compressed_size = LZMA_VLI_VALUE_UNKNOWN;
coder->block_options.uncompressed_size = LZMA_VLI_VALUE_UNKNOWN;