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1. 𝘾𝙔𝘽𝙀𝙍𝙁𝙍𝙄𝙀𝙉𝘿 (ninjawedding@sdfn-01.ninjawedding.org)'s status on Thursday, 01-Feb-2018 22:33:47 UTC 𝘾𝙔𝘽𝙀𝙍𝙁𝙍𝙄𝙀𝙉𝘿
   "unspecified behavior": "the behavior of this construct may vary across implementations but will conform to at least these guarantees"
   "undefined behavior": "idk lol ¯\_(ツ)_/¯ rm -rf /"
   • Hallå Kitteh repeated this.
   • 𝘾𝙔𝘽𝙀𝙍𝙁𝙍𝙄𝙀𝙉𝘿 (ninjawedding@sdfn-01.ninjawedding.org)'s status on Friday, 02-Feb-2018 00:03:54 UTC 𝘾𝙔𝘽𝙀𝙍𝙁𝙍𝙄𝙀𝙉𝘿

     in reply to
     Oh thanks
     Hallå Kitteh likes this.
     Hallå Kitteh repeated this.
   • Verius (verius@community.highlandarrow.com)'s status on Friday, 02-Feb-2018 18:34:39 UTC Verius

     in reply to
     @ninjawedding I've found a good way to reason about Undefined Behavior is that it's stuff that's incorrect but expensive in terms of performance to require a compiler to detect. For example to define null pointer derefences you actually would need to insert a check everywhere a pointer could be null. You can't just say "this crashes the program" since the C language spec doesn't actually mandate the behavior of the processor and OS (you can't force every OS to have a non-accessible page 0 and in deeply embedded situations you will want to use that page (or won't have virtual memory / page protection bits)). Meanwhile a compiler can do some useful tricks if it can know a pointer won't be dereferenced (since that would be a bug by the programmer). Same with strict aliasing, it allows the compiler to assume two pointers won't point to the same location and that has important effects on possible optimizations.
     Hallå Kitteh repeated this.
   • Hallå Kitteh (clacke@social.heldscal.la)'s status on Saturday, 03-Feb-2018 02:58:53 UTC Hallå Kitteh

     • Verius
     • Ꮢ๐ϲoᴄo Ⅿoԁｅm Ᏼaｓіliｓk
     • Jamey Sharp
     • ❄️🦊
     • 🐱egory theory
     • pasqui023
     @icefox @ninjawedding @jamey @pasqui023 @enkiv2 @sl2c @verius
     
     Undefined behavior:
     
     - Doctor, it hurts when I do this.
     - So don't do that.
     
     See also: http://wiki.c2.com/?WillyWonkaConflictResolution
     
     - What will happen if they collide?
     - Hasn't happened yet.