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    Starting with GCC 12 vectorization is enabled at the -O2 optimization level

    Given how prevalent -O2 is, this might actually be a hidden performance boost that will apply broadly to most of the Linux ecosystem.

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      Heads-up if you are compiling C++ code with -Wall: you will see a bogus warning it you assign/append a 1-char string literal to std::string. For example:

      void f (std::string& s)
      {
        s = "a";
        s += "b";
      }
      

      The bug report with the details is here: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105329

      I suggested that the GCC developers delay the release until this is fixed but looks like they went ahead without a fix. Hopefully in 12.2.

      You can usually work around the warning by changing to a char literal (which will also be more efficient).

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        You won’t find it yet in the release notes, but GCC 12.1 is finally able to compile recent D code, thanks to a big bump of the version of the D frontend integrated in GCC.

        The maintainer, Iain Buclaw, said that it will be documented more officially later.

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          Oh, thank you for pointing this out. This is a huge accomplishment for D !

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          Just noticed support for m68k on OpenBSD is gone in gcc 12.