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On 07/12/2018 07:10, Dale wrote: |
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> Now this is odd. I changed the settings and ran emerge. I decided to |
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> use -UDNa options to see if it would catch the changes. It did. Thing |
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> is, outside a few video type packages, there were no packages to be |
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> rebuilt. It seems very few packages actually notice those settings. |
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That's correct. Some software has compile-time flags to enable/disable |
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specific CPU features. The ebuilds for that software use CPU_FLAGS_X86 |
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to enable the relevant compile-time flags. |
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Most software doesn't contain low-level assembly code. Software that |
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does usually deals with video, audio or graphics, where hand crafted |
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low-level optimizations by the developers make sense. |
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If you want to see all of the installed packages that are affected, you |
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need to set CPU_FLAGS_X86 to an empty string: |
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CPU_FLAGS_X86="" |
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and then do "emerge -puDN --with-bdeps=y @world". This is because |
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CPU_FLAGS_X86 is not empty by default. It contains sse and sse2 by |
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default, because these are supported by all 64-bit CPUs. |
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> My only question left, will those flags affect the kernel image itself? |
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> I may just have to make sure my USB stick works. |
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No. The kernel configuration is completely separate from anything in |
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make.conf. CFLAGS or CPU_FLAGS_X86 do not affect kernel builds. |
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