Skip to content
  • Home Home Home, current page.
  • Moments Moments Moments, current page.

Saved searches

  • Remove
  • In this conversation
    Verified accountProtected Tweets @
Suggested users
  • Verified accountProtected Tweets @
  • Verified accountProtected Tweets @
  • Language: English
    • Bahasa Indonesia
    • Bahasa Melayu
    • Català
    • Čeština
    • Dansk
    • Deutsch
    • English UK
    • Español
    • Filipino
    • Français
    • Hrvatski
    • Italiano
    • Magyar
    • Nederlands
    • Norsk
    • Polski
    • Português
    • Română
    • Slovenčina
    • Suomi
    • Svenska
    • Tiếng Việt
    • Türkçe
    • Ελληνικά
    • Български език
    • Русский
    • Српски
    • Українська мова
    • עִבְרִית
    • العربية
    • فارسی
    • मराठी
    • हिन्दी
    • বাংলা
    • ગુજરાતી
    • தமிழ்
    • ಕನ್ನಡ
    • ภาษาไทย
    • 한국어
    • 日本語
    • 简体中文
    • 繁體中文
  • Have an account? Log in
    Have an account?
    · Forgot password?

    New to Twitter?
    Sign up
RichFelker's profile
Rich Felker
Rich Felker
Rich Felker
@RichFelker

Tweets

Rich Felker

@RichFelker

Yeah, I do @musllibc, FOSS & infosec stuff. But now is not the time for a mostly-/only-tech Twitter feed.

musl-libc.org
Joined March 2014

Tweets

  • © 2018 Twitter
  • About
  • Help Center
  • Terms
  • Privacy policy
  • Cookies
  • Ads info
Dismiss
Previous
Next

Go to a person's profile

Saved searches

  • Remove
  • In this conversation
    Verified accountProtected Tweets @
Suggested users
  • Verified accountProtected Tweets @
  • Verified accountProtected Tweets @

Promote this Tweet

Block

  • Tweet with a location

    You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more

    Your lists

    Create a new list


    Under 100 characters, optional

    Privacy

    Copy link to Tweet

    Embed this Tweet

    Embed this Video

    Add this Tweet to your website by copying the code below. Learn more

    Add this video to your website by copying the code below. Learn more

    Hmm, there was a problem reaching the server.

    By embedding Twitter content in your website or app, you are agreeing to the Twitter Developer Agreement and Developer Policy.

    Preview

    Why you're seeing this ad

    Log in to Twitter

    · Forgot password?
    Don't have an account? Sign up »

    Sign up for Twitter

    Not on Twitter? Sign up, tune into the things you care about, and get updates as they happen.

    Sign up
    Have an account? Log in »

    Two-way (sending and receiving) short codes:

    Country Code For customers of
    United States 40404 (any)
    Canada 21212 (any)
    United Kingdom 86444 Vodafone, Orange, 3, O2
    Brazil 40404 Nextel, TIM
    Haiti 40404 Digicel, Voila
    Ireland 51210 Vodafone, O2
    India 53000 Bharti Airtel, Videocon, Reliance
    Indonesia 89887 AXIS, 3, Telkomsel, Indosat, XL Axiata
    Italy 4880804 Wind
    3424486444 Vodafone
    » See SMS short codes for other countries

    Confirmation

     

    Welcome home!

    This timeline is where you’ll spend most of your time, getting instant updates about what matters to you.

    Tweets not working for you?

    Hover over the profile pic and click the Following button to unfollow any account.

    Say a lot with a little

    When you see a Tweet you love, tap the heart — it lets the person who wrote it know you shared the love.

    Spread the word

    The fastest way to share someone else’s Tweet with your followers is with a Retweet. Tap the icon to send it instantly.

    Join the conversation

    Add your thoughts about any Tweet with a Reply. Find a topic you’re passionate about, and jump right in.

    Learn the latest

    Get instant insight into what people are talking about now.

    Get more of what you love

    Follow more accounts to get instant updates about topics you care about.

    Find what's happening

    See the latest conversations about any topic instantly.

    Never miss a Moment

    Catch up instantly on the best stories happening as they unfold.

    1. John Carmack‏Verified account @ID_AA_Carmack 21 Dec 2015

      John Carmack Retweeted Melissa  💫

      Yes! Can anyone give an example on modern CPUs where being "undefined" is actually critical to perf on portability?https://twitter.com/0xabad1dea/status/679005753252970497 …

      John Carmack added,

      Melissa  💫 @0xabad1dea
      djb on fixing the C standard/C compilers to not make virtually 100% of real-world programs "undefined" https://groups.google.com/forum/#!msg/boring-crypto/48qa1kWignU/o8GGp2K1DAAJ …
      29 replies 44 retweets 74 likes
    2. Rich Felker‏ @RichFelker 22 Dec 2015
      Replying to @ID_AA_Carmack

      @ID_AA_Carmack Yes. If aliasing violations weren't UB the compiler would have to ins runtime aliasing chks everywhere or drop vectorization.

      1 reply 0 retweets 3 likes
    3. Rich Felker‏ @RichFelker 22 Dec 2015
      Replying to @RichFelker

      @ID_AA_Carmack If data races weren't UB the compiler would have to put barriers around all loads and stores.

      1 reply 0 retweets 4 likes
    4. Rich Felker‏ @RichFelker 22 Dec 2015
      Replying to @RichFelker

      @ID_AA_Carmack I can't believe we still need to explain this stuff to otherwise brilliant ppl like yourself and @hashbreaker.

      1 reply 0 retweets 0 likes
    5. John Carmack‏Verified account @ID_AA_Carmack 22 Dec 2015
      Replying to @RichFelker

      @RichFelker @hashbreaker I wouldn't argue races being UB, but having defined arithmetic semantics like Java is not a crazy thing to consider

      1 reply 0 retweets 0 likes
      Rich Felker‏ @RichFelker 22 Dec 2015
      Replying to @ID_AA_Carmack

      @ID_AA_Carmack Defining the behavior of signed overflow eliminates the ability of automated tools to diagnose overflow errors.

      8:36 AM - 22 Dec 2015
      3 replies 0 retweets 0 likes
        1. New conversation
        2. Ion Todirel‏ @iontodirel 22 Dec 2015
          Replying to @RichFelker

          @RichFelker @ID_AA_Carmack not really, you can still define the overflow by throwing an exception or setting an error flag

          1 reply 0 retweets 0 likes
        3. Rich Felker‏ @RichFelker 22 Dec 2015
          Replying to @iontodirel

          @iontodirel @ID_AA_Carmack You missed the point: if the overflow behavior is defined, valid programs can use it; tools can't assume it's err

          2 replies 0 retweets 0 likes
        4. John Carmack‏Verified account @ID_AA_Carmack 22 Dec 2015
          Replying to @RichFelker

          @RichFelker @iontodirel I never considered that point of view; not sure what I think about it yet. Such tools certainly aren't everywhere.

          0 replies 0 retweets 1 like
        5. End of conversation
        1. Rich Felker‏ @RichFelker 22 Dec 2015
          Replying to @RichFelker

          @ID_AA_Carmack It's because unsigned arith has well-defined (modular arith) behavior that ubsan, valgrind, etc. can't catch size overflows.

          0 replies 1 retweet 0 likes
          Thanks. Twitter will use this to make your timeline better. Undo
          Undo
        1. {{data.user}}‏ @phenlix 23 Dec 2015
          Replying to @RichFelker

          @RichFelker @ID_AA_Carmack not an issue, those checks would have to be performed as source analysis instead of black-box observers

          0 replies 0 retweets 0 likes
          Thanks. Twitter will use this to make your timeline better. Undo
          Undo

      Loading seems to be taking a while.

      Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.

        Promoted Tweet

        false

        • © 2018 Twitter
        • About
        • Help Center
        • Terms
        • Privacy policy
        • Cookies
        • Ads info