diff --git a/cmake/tuklib_integer.cmake b/cmake/tuklib_integer.cmake
index d7e2e28c..949d2d9f 100644
--- a/cmake/tuklib_integer.cmake
+++ b/cmake/tuklib_integer.cmake
@@ -59,9 +59,8 @@ function(tuklib_integer TARGET_OR_ALL)
         endif()
     endif()
 
-    # 16-bit and 32-bit unaligned access is fast on x86(-64),
-    # big endian PowerPC, and usually on 32/64-bit ARM too.
-    # There are others too and ARM could be a false match.
+    # Unaligned access is fast on x86(-64), big endian PowerPC, and usually on
+    # 32/64-bit ARM too. There are others too and ARM could be a false match.
     #
     # Guess the default value for the option.
     # CMake's ability to give info about the target arch seems bad.
@@ -81,7 +80,7 @@ function(tuklib_integer TARGET_OR_ALL)
     endif()
     option(TUKLIB_FAST_UNALIGNED_ACCESS
            "Enable if the system supports *fast* unaligned memory access \
-with 16-bit and 32-bit integers."
+with 16-bit, 32-bit, and 64-bit integers."
            "${FAST_UNALIGNED_GUESS}")
     tuklib_add_definition_if("${TARGET_OR_ALL}" TUKLIB_FAST_UNALIGNED_ACCESS)
 
diff --git a/m4/tuklib_integer.m4 b/m4/tuklib_integer.m4
index 9e104729..ab9a4056 100644
--- a/m4/tuklib_integer.m4
+++ b/m4/tuklib_integer.m4
@@ -8,8 +8,8 @@
 #   Checks for tuklib_integer.h:
 #     - Endianness
 #     - Does the compiler or the operating system provide byte swapping macros
-#     - Does the hardware support fast unaligned access to 16-bit
-#       and 32-bit integers
+#     - Does the hardware support fast unaligned access to 16-bit, 32-bit,
+#       and 64-bit integers
 #
 # COPYING
 #