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I may be stating the obvious, depending on what you know, but as far as I |
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understand it goes something like this: |
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|
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Info goes to the cpu of a 32 bit machine in chunks of, you guessed it: 32 |
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bits. Obviously with 64 bit machines it's 64 bit chunks, but the interesting |
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thing is that many if not all 64 bit chips can recognize when they get |
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chunks of 32 bit code, and emulate. I think that the gcc64 use flag means |
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that you will compile your kernel in 64 bit code. That may mean that you |
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compiled your kernel with a 32 bit compiler before. Now considering you're |
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on the gentoo-amd64 forum, I assume you have x86_64 gentoo and that your |
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arch is set to x86_64, so the use flag seems a bit redundant to me. I'm |
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probably wrong, I have no experience with this, it's late, I'm tired. |
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Please, someone correct me if I'm just being an idiot, or if that's not the |
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question you asked. |
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|
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In the unlikely event that I'm right, here would be some pro's and cons. You |
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may not be fully unlocking the potential of your shiny new 64 bit machine by |
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using a 32 bit kernel. The pro would be that you may (not sure, depends on |
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what your kernel is before you recompile) be able to use 32 bit software. |
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Many closed source programs and some programs that emulate the closed source |
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stuff are in 32 bit, and have trouble in 64. I think you'd only run into |
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trouble with java and flash using 64 bit kernel. Adobe still doesn't offer |
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64 bit flash to my knowledge, and java is a bit of a pain in any flavor. |
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|
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Again, I may be just babbling, and if I spent this e-mail regurgitating |
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things that you already know, I apologize. That was my interpretation, hope |
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it helped. |
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|
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-Peter |
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|
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|
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On 12/27/06, Simon Stelling <blubb@g.o> wrote: |
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> |
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> Robert Cernansky wrote: |
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> > Can anybody explain more? What are the pros and cons to switch it |
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> on/off? |
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> |
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> The USE flag is only effective on ppc64 and sparc where the kernel |
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> sometimes is the only code that is compiled 64bit and therefore a |
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> seperate, much smaller version of gcc is used to build the kernel. The |
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> flag should in fact be masked everywhere except for those profiles, |
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> which is what bug 144535 [1] deals with. |
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> |
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> [1] http://bugs.gentoo.org/show_bug.cgi?id=144535 |
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> |
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> -- |
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> Kind Regards, |
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> |
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> Simon Stelling |
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> Gentoo/AMD64 Developer |
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> -- |
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> gentoo-amd64@g.o mailing list |
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> |
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> |
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