state of a typical C compiler, 1998

[joe@f.duriansoftware.com]

state of a typical C compiler, 1998

[joe@f.duriansoftware.com]

this was a classic @regehr tweet that i had to repost to preserve for future generations

[atax1a@infosec.exchange]

@joe 1 >> INT_MAX is fucking sending us

[atax1a@infosec.exchange]

@joe we can see exactly how it happens

[regehr@mastodon.social]

@joe I boosted it Joe!!!!!!!

[thalia@discuss.systems]

@joe Why would anyone think it's a good idea to const-eval shifts, one bit at a time‽

[regehr@mastodon.social]

@joe btw-- this is the same person who, more than 30 years earlier, coined the term "peephole optimization" 👀

https://dl.acm.org/doi/pdf/10.1145/364995.365000

[thalia@discuss.systems]

@joe "The famous Pentium divide bug (we did not catch it but we could have)": well aren't they sophisticated.

[regehr@mastodon.social]

@joe I exchanged a few emails with him many years back. but I think, clearly, most of us here should have bought him a couple beers

[pervognsen@mastodon.social]

@joe I love that the experience of reading that table is like "sure, I can see how that would happen" and then you get to the TWENTY MINUTE COMPILE TIME. The "server crash" one is fun too.

[atax1a@infosec.exchange]

@regehr @joe ceci nes pas une peephole optimization

[ratsnakegames@mastodon.social]

@joe the heck is -!0

[ratsnakegames@mastodon.social]

@joe if you put that in your code, you deserve a compiler error

[rotopenguin@mastodon.social]

@atax1a @joe

[joe@f.duriansoftware.com]

@ratsnakegames not much, what’s -! With you

[regehr@mastodon.social]

@joe "Twenty-minute compile time" is so perfect and understated

[regehr@mastodon.social]

@joe of course with modern OOO processors this would be like 0.2 seconds and would go unnoticed

[cr1901@mastodon.social]

@regehr @joe "Server crash" is doing some work here :D

[regehr@mastodon.social]

@cr1901 @joe it's so good because it implicates the OS as an accomplice

[rotopenguin@mastodon.social]

@regehr @joe good thing it was on the best OO processor of its day, the iAPX432