diff --git a/src/liblzma/check/crc_common.h b/src/liblzma/check/crc_common.h
index 552219fe..372ae4a4 100644
--- a/src/liblzma/check/crc_common.h
+++ b/src/liblzma/check/crc_common.h
@@ -74,7 +74,8 @@
 #undef CRC_USE_IFUNC
 #undef CRC_USE_GENERIC_FOR_SMALL_INPUTS
 
-// If CLMUL cannot be used then only the generic slice-by-four is built.
+// If CLMUL cannot be used then only the generic slice-by-eight (CRC32)
+// or slice-by-four (CRC64) is built.
 #if !defined(HAVE_USABLE_CLMUL)
 #	define CRC_GENERIC 1