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Joined 1 year ago
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Cake day: June 4th, 2025

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  • Thanks for the additional details.

    With the security vulnerabilities found in older chips that require either a revised architecture or otherwise take huge performance penalties to mitigate (e.g. Meltdown and Spectre), most enterprise customers upgraded their hardware older than 2008 in recent years.

    Are you sure this is really one of the reasons? I thought that Meltdown and Spectre affected much newer CPUs, so that v1/v2 didn’t line up with that. The Wikipedia article on Meltdown says up to 2018 CPUs. The one on Spectre says all pre-2019 CPUs that use branch prediction.



  • The key reason for doing this, as stated in the article:

    ultimately they say “the straw that broke the camel’s back” to abandon Red Hat Enterprise Linux for their industrial accelerator-control computers was the “-march=x86-64-v2” compiler flag default as “forced obsolescence” for old hardware.

    From what I understand, the v2 option requires relatively newer CPU instruction sets, making it incompatible with some older CPUs, even 64 bit ones. I don’t know what is gained by using the v2 flag, but I would imagine that it may be something performance-related, by more fully utilizing those newer instruction sets.


  • That’s not true at all. Like I said, copyleft relies completely on copyright. It was not at all created in opposition to copyright. It was created in opposition to proprietary (i.e., “unfree”) software. Here, from the Wikipedia article on Copyleft (emphasis mine):

    The concept of copyleft was described in Richard Stallman’s GNU Manifesto in 1985, where he wrote:[6]

    GNU is not in the public domain. Everyone will be permitted to modify and redistribute GNU, but no distributor will be allowed to restrict its further redistribution. That is to say, proprietary modifications will not be allowed. I want to make sure that all versions of GNU remain free.

    This is impossible to do without copyright existing. Like I mentioned before, without copyright laws, companies can take any code they wish, with any license, and use it in their proprietary software without sharing their modifications.

    Another reference directly from the FSF: “Copyleft is a tool that works within copyright law” (emphasis mine)