Lightnews — Scholar-powered news

Jonathan Aldrich @jonathanaldrich.bsky.social · 22h

Also check out our POPL'24 paper on the latest theory underlying Gradual Verification, which Hazel's work (with Long Nguyen and me) extends:

dl.acm.org/doi/10.1145/...

Sound Gradual Verification with Symbolic Execution | Proceedings of the ACM on Programming Languages

Gradual verification, which supports explicitly partial specifications and verifies them with a combination of static and dynamic checks, makes verification more incremental and provides earlier feedback to developers. While an abstract, weakest ...

dl.acm.org

2

Jonathan Aldrich @jonathanaldrich.bsky.social · 22h

For more information about gradual verification, check out our TOPLAS'25 paper on our system and empirical results:

dl.acm.org/doi/10.1145/...

Gradual C0: Symbolic Execution for Gradual Verification | ACM Transactions on Programming Languages and Systems

Current static verification techniques such as separation logic support a wide range of programs. However, such techniques only support complete and detailed specifications, which places an undue burd...

dl.acm.org

1 1

Jonathan Aldrich @jonathanaldrich.bsky.social · 22h

Next, at 16:50, Hazel Torek will talk about how to extend our theory of gradual verification with unfolding expressions. Unfolding is important for modular specification; it allows making assertions about state that is owned by a separate predicate.

1 1

Jonathan Aldrich @jonathanaldrich.bsky.social · 22h

First, at 16:25 I'll give an overview of gradual verification, with a specific focus on gradual support for ownership (following the theme of IWACO). Learn how gradual verification makes specification more practical, and how we can check ownership dynamically!

1 1

Jonathan Aldrich @jonathanaldrich.bsky.social · 22h

#GradualVerification helps developers specify code one component at a time, checking statically where possible and dynamically where necessary.

Come see doubleheader talks on #GradualVerification in #IWACO at #SPLASH 2025 / @icfp-conference.bsky.social! 16:25-17:15 in Peony room 4412.

1 1 4

Jonathan Aldrich @jonathanaldrich.bsky.social · 23h

Catarina's talk is in the HATRA workshop, at 10:50am in Orchid room 4201A-4201B. The paper is coauthored with Abigail Reese, @alcidesfonseca.com, and me. Check it out, open access in the @acm.org digital library: dl.acm.org/doi/10.1145/...

Usability Barriers for Liquid Types | Proceedings of the ACM on Programming Languages

Liquid types can express richer verification properties than simple type systems. However, despite their advantages, liquid types have yet to achieve widespread adoption. To understand why, we conducted a study analyzing developers' challenges with ...

dl.acm.org

1 4

Jonathan Aldrich @jonathanaldrich.bsky.social · 23h

#LiquidTypes are a lightweight way to specify and check code properties. What stands in the way of more widespread adoption?

Today at #SPLASH 2025 / @icfp-conference.bsky.social: @catarinavgamboa.bsky.social will re-present our #PLDI2025 paper on Usability Barriers for Liquid Types.

1 2 7

Jonathan Aldrich @jonathanaldrich.bsky.social · 1d

PLP 5.5: Compiling for Modern Processors - youtu.be/C6N-4GUJ9bY

Also check out the whole Programming Language Pragmatics playlist: tinyurl.com/PLP5vids

Chapter 5 in our book is freely available at the companion site: mlscott14627.github.io/PLP5e_online...

PLP 5.5: Compiling for Modern Processors

YouTube video by Jonathan Aldrich

youtu.be

1

Jonathan Aldrich @jonathanaldrich.bsky.social · 1d

How does one write efficient code for modern processors?

My new Programming Language Pragmatics video covers a big part of the answer: using instruction scheduling and register allocation to reduce pipeline stalls that compromise performance!

1 1 6

Jonathan Aldrich @jonathanaldrich.bsky.social · 1d

Given the diversity of thought in programming languages, I may one day be that too, for someone!

Jonathan Aldrich @jonathanaldrich.bsky.social · 2d

Achievement unlocked: was recognized as "the guy who does the programming languages videos" 😀

3 1 40

Jonathan Aldrich @jonathanaldrich.bsky.social · 4d

PLP 5.3-5.4: Instruction set architecture & how architecture affects implementation - youtu.be/KWMwVgQ87jU

Also check out the whole Programming Language Pragmatics playlist: tinyurl.com/PLP5vids

Chapter 5 in our book is freely available at the companion site: mlscott14627.github.io/PLP5e_online...

PLP 5.3-5.4: Instruction set architecture and how architecture affects implementation

YouTube video by Jonathan Aldrich

youtu.be

1

Jonathan Aldrich @jonathanaldrich.bsky.social · 4d

What instructions do modern processors support? What can you express with them? And how are processors implemented to execute them efficiently? Get a high-level overview in my latest Programming Language Pragmatics video!

1 2

Jonathan Aldrich @jonathanaldrich.bsky.social · 5d

PLP 5.2: Data Representation in Computer Architecture - youtu.be/UeNtlzpLfaM

Also check out the whole Programming Language Pragmatics playlist: tinyurl.com/PLP5vids

Chapter 5 of our book is freely available at the companion site: mlscott14627.github.io/PLP5e_online...

youtu.be

2

Jonathan Aldrich @jonathanaldrich.bsky.social · 5d

How is data represented in computer architectures?

My latest Programming Language Pragmatics video gives compiler writers information about twos-complement integers, floating point numbers, and little-endian vs. big-endian byte order, useful for manipulating data in target code.

1 4

Jonathan Aldrich @jonathanaldrich.bsky.social · 6d

Fortunately I tried the link early in the day, discovered the problem, communicated with the student, and all is well. But WTF is the institution thinking?

Yeah, looking at you, Stanford.

Jonathan Aldrich @jonathanaldrich.bsky.social · 6d

Went to fill out a recommendation letter request and THE LINK HAD EXPIRED!

OMG, this is TERRIBLE policy. The link had to be regenerated by the student, and what if it's the day it's due and there's no time for a round-trip? Actually punishes the most responsible students, who send links early.

1 4

Jonathan Aldrich @jonathanaldrich.bsky.social · 6d

LOL I missed an opportunity there!

Jonathan Aldrich @jonathanaldrich.bsky.social · 6d

Now ICE is shooting praying priests with pepper balls. And MAGA is supposed to be pro-Christianity?

Preorder Read This When Things Fall Apart @mskellymhayes.bsky.social · 24d

CW: protester being struck in the head by a pepper ball

Footage I took earlier of the moment Reverend David Black, a regular protester outside of the Broadview Detention Center, was shot in the head with a pepper ball by ICE agents on the roof of the facility.

3

Jonathan Aldrich @jonathanaldrich.bsky.social · 8d

PLP 5.1: The Memory Hierarchy - youtu.be/FD0XVnNE1u0

Also check out the whole Programming Language Pragmatics playlist: tinyurl.com/PLP5vids

PLP 5.1: The Memory Hierarchy

YouTube video by Jonathan Aldrich

youtu.be

Jonathan Aldrich @jonathanaldrich.bsky.social · 8d

Language implementers need a solid grounding in processor architecture in order to understand how to generate good code. In my latest Programming Language Pragmatics video, I put on my "architecture hat" to cover the memory hierarchy and explain the implications for code generation.

2 15

Jonathan Aldrich @jonathanaldrich.bsky.social · 8d

Nice, thanks for the explanation! Now I need to sit down with a couple of linear functions and see how this (matmul = function composition) works. 😀

Jonathan Aldrich @jonathanaldrich.bsky.social · 8d

LOL I never got anything BUT the formulaic matmul (at least, nothing that stuck). Is there a nice explanation of this outside the precalc book?

1

Jonathan Aldrich @jonathanaldrich.bsky.social · 9d

Some real Nazi thought policing there: "people should not be coming to the Super Bowl unless they're law-abiding Americans who love this country."

1

Reposted by Jonathan Aldrich

Andrea Junker @strandjunker.com · 10d

“Terrible things are happening outside. Poor helpless people are being dragged out of their homes. Families are torn apart. Men, women, and children are separated. Children come home from school to find that their parents have disappeared.”

Diary of Anne Frank
January 13, 1943

260 8K 17K