Ah, thanks for the background, Mike! What needs to be done then to ensure the document gets updated? Should I file a proper bug report somewhere?
On Tue, Jun 11, 2013 at 5:31 AM, Mike Herrick <[email protected]> wrote: > This point appears to have come up multiple times over the years, with this > post being the earliest I could find: > > http://communities.mentor.com/community/cs/archives/cxx-abi-dev/msg01527.html > > We proposed striking the "without leading zeros" wording in this post, but > those changes were never integrated into the document: > > http://communities.mentor.com/community/cs/archives/cxx-abi-dev/msg02291.html > > Since then, the issue of mangling a floating-point zero was also brought up > by Jason in a post titled "Mangling 0.0f" dated January 18, 2012 (the mailing > list archives don't appear to cover newer posts): > >> I notice that G++ and EDG mangle 0.0f as Lf00000000E, while clang produces >> Lf0E. I assume that the latter is based on the "without leading zeroes" in >> the ABI document, while the former is based on the "fixed-length" earlier in >> the sentence. > > > It seems the document should be updated to prevent future confusion. > > Mike Herrick > Edison Design Group > > On Jun 11, 2013, at 2:18 AM, Matthew Dempsky <[email protected]> wrote: > >> On Mon, Jun 10, 2013 at 10:40 PM, Dennis Handly <[email protected]> wrote: >>>> From: Matthew Dempsky <[email protected]> >>>> Can someone please clarify for me how floating-point literals can be >>>> encoded as a "fixed-length" string but "without leading zeros"? E.g., >>>> how should 0.0f be encoded? >>> >>> I would assume you remove all but the only zero nibble. >>> I.e. The last zero isn't leading. >> >> For what it's worth, GCC 4.6.3 and Clang 3.2 when targeting >> x86_64-linux-gnu both mangle 0.0f as Lf00000000E. >> >> (But Clang 3.2 mangles 0.0l as Le3fff8000000000000000E, whereas GCC >> 4.6.3 mangles it as Le0000000000003fff8000000000000000E. I don't have >> newer versions readily available to check.) >> _______________________________________________ >> cxx-abi-dev mailing list >> [email protected] >> http://sourcerytools.com/cgi-bin/mailman/listinfo/cxx-abi-dev > _______________________________________________ cxx-abi-dev mailing list [email protected] http://sourcerytools.com/cgi-bin/mailman/listinfo/cxx-abi-dev
