[Bug c/34764] New: A Flame About 64-bit Pointers

pgquiles at elpauer dot org gcc-bugzilla@gcc.gnu.org
Sat Jan 12 22:29:00 GMT 2008


(Please note this is a copy & paste from Donald E. Knuth's homepage:
http://www-cs-faculty.stanford.edu/~uno/news.html - Given who he is, I think
the issue should receive a bit of love)

It is absolutely idiotic to have 64-bit pointers when I compile a program that
uses less than 4 gigabytes of RAM. When such pointer values appear inside a
struct, they not only waste half the memory, they effectively throw away half
of the cache. 
 The gcc manpage advertises an option "-mlong32" that presumably does what I
want. Namely, it should compile code for my x86-64 architecture, taking
advantage of the extra registers etc., but it should also know that my program
is going to live inside a 32-bit virtual address space. 
 Unfortunately, the gcc I got with Ubuntu 7.10 says that -mlong32 is an unknown
option. Probably that happens because programs compiled with this convention
will need to be loaded with a special version of libc. 
 Please, somebody, make that possible.


-- 
           Summary: A Flame About 64-bit Pointers
           Product: gcc
           Version: 4.1.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: pgquiles at elpauer dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34764



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