We've been running our MySQL boxen compiled for x86_64 on 4GB Opterons for some time.
Postgres had some issues back in version 7 on some versions of Solaris.
What software are you aware of that doesn't "support being built 64-bit"?
Afterstep had some issues a while ago:
http://sunportal.sunmanagers.org/pipermail/summaries/2003-March/003425.html
My introduction to Linux started in 1999 with LinuxPPC on my Macintosh G3. Lots of bright linux programmers made all sorts of assumptions about endianness and things like xmms wouldn't compile. Programs like Jack the Ripper had assembler in them that would explode spectacularly. These same people are out there, right now, writing code on their 32-bit athlons or whatever, assuming that the rest of the world uses their flavor of linux on their flavor of hardware.
It's nice to see that MySQL doesn't suffer from these problems, but its previous failings (subselects, pl/sql, still lack of ACID, etc), left me in doubt of its ability to build natively n64.
Just been bitten many times by porting software. As I said, my background is with many Unixes. Porting stuff from Linux to IRIX is probably the worst, especially when the linux guy used gcc, and I wanted to use the SGI compiler. But I digress.
Happy for mysql. Would anyone else like to troll me?
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