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> > A few comments I've been meaning to make. |
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> > |
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> > 1. According to the GCC documentation you shouldn't be using |
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-m<processor> |
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> > any more. It's been depreciated in favor of -mcpu<processor>. |
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> I know that. The mpentium etc. flags wre in the originl make.conf, the |
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things |
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> I added were -march=x -mcpu=x. I'll change mpentium for march=pentium if |
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I |
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> haven't already. |
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|
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Just making an observation of what I've seen to date. Haven't seen your |
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additions yet. In fact, I just downloaded them. |
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|
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> > |
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> > 2. You don't need to use -mcpu usually with -march as -march sets -mcpu |
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> > for you. I say usually 'cause there's an AMD processor (can't remember |
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> > which) that uses a different instruction set than the default set by the |
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> > -march it uses. |
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> I think you're wrong. If I say march=i486 mcpu=i586 this means the binary |
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> will run on any 486 or better, but is optimized for the 586. |
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|
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You're correct. I had the nagging feeling there was a second exception |
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but decided I was crazy after thinking about it for a few seconds. |
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Didn't have the time then to look it up. |
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|
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> > |
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> > 3. The usage of processor names has been depreciated as well. Should |
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> > use i586, etc. instead. |
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> For intel processors maybe. However AMD's k6, though a 586, is better |
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than a |
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> Pentium, and the Athlon, though a 686, is better than a Pentium3. |
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> Although it really would be better if gcc allowed for flags of |
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instruction |
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> sets etc. so that you could define your 'custom processor' by saying, use |
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> MMX+3DNow!2+sse. Than we'd know exactly what optimization it was doing. |
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|
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Now arguments there. It really peaves me that it won't use the MMX |
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extensions on my Pentium 167 +MMX machine. |
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