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mattgodbolt

1,194 karma · joined March 1, 2014

Master-of-none developer. Ex-games industry, ex-Google, ex-startup.

Primary hacker of Compiler Explorer - https://godbolt.org

Mucks about with Javascript emulators - https://miracle.xania.org, https://bbc.xania.org/ and in C++ too https://spectrum.xania.org

Some OSS on https://github.com/mattgodbolt/ and https://github.com/compiler-explorer

submissionscomments
mattgodbolt··on When compilers surprise you
It may be a different post, but I covered this earlier this month in the same series of blog posts/YouTube videos.
mattgodbolt··on When compilers surprise you
This exact content was only posted today? :)
mattgodbolt··on When compilers surprise you
I dunno he can honestly be quite a jerk sometimes
mattgodbolt··on Pop Goes the Population Count?
All that and more: https://graphics.stanford.edu/~seander/bithacks.html#CountBi... :)
mattgodbolt··on Addressing the adding situation
My nefarious plan has been exposed!!
mattgodbolt··on Addressing the adding situation
Tell me about it...someone turned my name into a verb...
mattgodbolt··on Addressing the adding situation
Ahhh! Thanks: that helps me understand where I picked up my misinformation!
mattgodbolt··on Addressing the adding situation
Hey now; let's not get ahead too far :) I'm trying to keep each one bite-sized...I don't think you'll be (too) disappointed at the next few episodes :)
mattgodbolt··on Advent of Compiler Optimisations 2025
Awww thanks again Adam :blush:
mattgodbolt··on Advent of Compiler Optimisations 2025
I _think_ so, but this could all be some kind of simulation, I guess? :)
mattgodbolt··on Why xor eax, eax?
That's just some weird side hobby of his.
mattgodbolt··on Teaching an Old Dog New Tricks [video]
Exploring contemporary vs "old(er) school" C++ through the medium of emulating a childhood computer
mattgodbolt··on Compiler Explorer Cost Transparency
Despite the bounce a nice person replied and is helping me apply! Thanks for bringing this up!! :)
mattgodbolt··on Compiler Explorer Cost Transparency
Well; I emailed the address at the AWS link and got: "The recipient's mailbox is full and can't accept messages now. Please try resending your message later, or contact the recipient directly." :)
mattgodbolt··on Compiler Explorer Cost Transparency
Thanks so much! I've not had too much success chasing down no-strings-attached stuff. Grafana and Sentry are pretty cheap compared to the AWS, so I didn't spend too much time...

Twice I've had folks from AWS approach me about helping, but it fizzled out. The best I've had is a pal who was a salesperson used to slip me a few "$100 new customer vouchers" every now and then I could redeem.

The pre-allocation means some kind of commitment: every time I've looked I've baulked at dropping many thousands of dollars in one go (and it screws up my terrible book-keeping :D ). I should probably revisit it. It's really nice to know I'm not paying for things I don't "need", but it's unlikely CE usage will drop _that much_ in the next year or two (say).

I'll take a look at the OSS stuff you linked: thank you!

mattgodbolt··on How Compiler Explorer Works in 2025
So sorry to disappoint you, but I'm really not :D
mattgodbolt··on How Compiler Explorer Works in 2025
I'll do a follow-up post sometime on where the money goes.
mattgodbolt··on How Compiler Explorer Works in 2025
They are already free and available. Check out our "infra" repo and the ce_install tool and/or just hack the S3 URLs
mattgodbolt··on Compiler Explorer and the promise of URLs that last forever
He didn't know at the time but he's definitely pleased this is happening and will get to looking at it tomorrow!
mattgodbolt··on Compiler Explorer and the promise of URLs that last forever
Thanks! It's been a fun learning experience. I just found out the internet archive has a much more comprehensive effort going so it might have been in vain, but I tried :)
mattgodbolt··on Compiler Explorer and the promise of URLs that last forever
Thanks! Someone posted on GitHub about that and I'll be looking at that tomorrow!
mattgodbolt··on Compiler Explorer and the promise of URLs that last forever
Oh and traffic: https://stats.compiler-explorer.com/
mattgodbolt··on Compiler Explorer and the promise of URLs that last forever
It was a simpler time and I didn't want the responsibility of storing other people's data. We do now though!
mattgodbolt··on Compiler Explorer and the promise of URLs that last forever
I'm not sure why so?
mattgodbolt··on Compiler Explorer and the promise of URLs that last forever
We've done alright so far: 13 years this week. I have funding for another year and change even assuming growth and all our current sponsors pull out.

I /am/ thinking about a foundation or similar though: the single point of failure is not funding but "me".

mattgodbolt··on Matt Godbolt sold me on Rust by showing me C++
Wow that guy, eh? He seems to turn up everywhere :D
mattgodbolt··on Show HN: Program Explorer, a container playground
Congrats! It's amazing to see what CE has inspired! Thanks for the shout out :)
mattgodbolt··on Xmas.c (1988)
Still works on trunk (if you turn off the warning :))

https://compiler-explorer.com/z/hGvs1e9jo

mattgodbolt··on Dogbolt Decompiler Explorer
It's never been called anything but either "GCC Explorer" or "Compiler Explorer", by me, anyway... The URL it's accessible for is an accident of the one I had hanging around :) (it's now available at compiler-explorer.com too, but...the name other people use has stuck so I'll never be able to reclaim my own domain...)
mattgodbolt··on Matt Godbolt: Five things you didn't realise your CPU did for you
I think the point that was being made is that the _dynamic_ performance of the system is important too: branch prediction, cache access patterns etc, can't always be determined ahead of time, or even at the point the program is being installed or first run. This is why JIT compilers exist that tune the program as it runs, and this is what effectively is also happening at the micro-op level in your CPU as it runs.
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