liblzma: Update a comment.

The C standards don't allow an empty translation unit which can be
avoided by declaring something, without exporting any symbols.

When I committed f644473a211394447824ea00518d0a214ff3f7f2 I had
a feeling that some specific toolchain somewhere didn't like
empty object files (assembler or maybe "ar" complained) but
I cannot find anything to confirm this now. Quite likely I
remembered nonsense. I leave this here as a note to my future self. :-)

diff --git a/src/liblzma/check/crc64_table.c b/src/liblzma/check/crc64_table.c
index 6f9adb04d57d3df3ea3d893a01d6096923433d68..688e527b0fd1264292be0f3e93773a2a203d934b 100644 (file)
--- a/src/liblzma/check/crc64_table.c
+++ b/src/liblzma/check/crc64_table.c
@@ -18,8 +18,7 @@
 #if (defined(__x86_64__) && defined(__SSSE3__) \
                        && defined(__SSE4_1__) && defined(__PCLMUL__)) \
                || (defined(__e2k__) && __iset__ >= 6)
-// No table needed but something has to be exported to keep some toolchains
-// happy. Also use a declaration to silence compiler warnings.
+// No table needed. Use a typedef to avoid an empty translation unit.
 typedef void lzma_crc64_dummy;
 
 #else