openjdk/jdk on Hacker News

…code in question takes into account that the value read might be garbage. See the big comment here: https://github.com/openjdk/jdk/commit/29397d29baac3b29083b1b... On current CPUs and operating systems, this is not an optimization, so the…

comment by fweimer · 2024-03-18 · in macOS Sonoma 14.4 might break Java on your machine

…for the JVM, because it prevents a fast path being taken for stack thawing for virtual threads: https://github.com/openjdk/jdk/blob/d32ce65781c1d7815a69ceac...

comment by BinaryRage · 2024-03-17 · in The return of the frame pointers

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JDK-8180450: secondary_super_cache does not scale well

story by mfiguiere · 2024-03-14 · 0 comments

https://github.com/openjdk/jdk/tree/master/src/jdk.compiler/... , Wiki citation for good measures https://en.wikipedia.org/wiki/Javac . Maybe you're thinking of Hotspot, which is written in C++.

comment by hyperpape · 2024-01-04 · in The One Billion Row Challenge

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AVX2 intrinsics for Arrays.sort methods (int, float arrays)

story by mfiguiere · 2023-12-17 · 2 comments

…internally, it just supports various bit-related operations as-if it were two's complement. https://github.com/openjdk/jdk/blob/28026434f74726d72857e781...

comment by o11c · 2023-11-23 · in A gentle introduction to two's complement

…expose their users to bugs on account of this implementation. EDIT: … ha, sure looks like it https://github.com/openjdk/jdk/blob/a2c0fa6f9ccefd3d1b088c51...

comment by leoh · 2023-11-20 · in Setenv Is Not Thread Safe and C Doesn't Want to Fix It

Map doesn't implement the Collection interface. https://github.com/openjdk/jdk/blob/master/src/java.base/sha...

comment by vips7L · 2023-11-14 · in Java JEP 461: Stream Gatherers

…in or have parts of their implementations in C++. See JS ( https://github.com/v8/v8)and Java GC ( https://github.com/openjdk/jdk/tree/36de19d4622e38b6c00644b0... ) I am not an expert on Java (or C++), so if someone knows better or can add…

comment by gp · 2023-11-01 · in C++23: Removing garbage collection support

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Make Immutable Maps ValueBased

story by mfiguiere · 2023-10-19 · 0 comments

…details. Check out this function which helps determine if instance fields are trusted: https://github.com/openjdk/jdk/blob/edd454b502b9bacde5549282...

comment by vips7L · 2023-10-07 · in Java 21 VirtualThreads vs. Clojure Lazy Seqs

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Prototype of a Panamization of the NetworkInterface Class

story by mfiguiere · 2023-09-20 · 1 comment

…such questions. A small aside: The README uses `Paths/get`, which might be deprecated eventually: https://github.com/openjdk/jdk/blob/b16e5584abcae18fdcc4494f... Should just use `Path/of` directly. BTW, I thought I would give it a try, but…

comment by onetom · 2023-09-19 · in Show HN: Pile Programming Language

…semantics on different platforms is so annoying and why C standard left itself a nice shortcut. [0] https://github.com/openjdk/jdk/blob/d27daf01d6361513a815e783... [1] https://github.com/openjdk/jdk/blob/d27daf01d6361513a815e783...

comment by Joker_vD · 2023-08-17 · in A Guide to Undefined Behavior in C and C++ (2010)

…wasn't the correct word. The feature was implemented in OpenJDK by a Microsoft employee. [0] https://github.com/openjdk/jdk/pull/9073 [1] https://github.com/openjdk/jdk/pull/12897

comment by vips7L · 2023-08-06 · in MS Build of OpenJDK now with enhanced escape analysis enabled by default

…source Java distro" ? You mean "open source build for Java", because OpenJDK is open source, here: https://github.com/openjdk/jdk One can build JDK themselves, it is not that hard.

comment by krzyk · 2023-07-05 · in Let's have a chat about Java licensing, says unsolicited Oracle email

PR for this commit: https://github.com/openjdk/jdk/pull/14224

comment by mfiguiere · 2023-06-15 · in Add intrinsic for float/double modulo for x86 AVX2 and AVX512 in OpenJDK

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Add intrinsic for float/double modulo for x86 AVX2 and AVX512 in OpenJDK

story by mfiguiere · 2023-06-15 · 1 comment

FWIW, there's an open PR and discussion around the code for this: https://github.com/openjdk/jdk/pull/9779

comment by gavinray · 2023-06-11 · in A compact overview of JDK 21’s “frozen” feature list

…...) The concrete implementation in doTypeSwitch currently says “Dumbest possible strategy”: https://github.com/openjdk/jdk/blob/master/src/java.base/sha... There is no @IntrinsicCandidate, so I don't expect Hotspot to special-case any of…

comment by fweimer · 2023-06-11 · in A compact overview of JDK 21’s “frozen” feature list

Glorious. Check out the implementation here: https://github.com/openjdk/jdk/blob/6d140d5b8bc4d6b3daa16f72...

comment by throwaway2037 · 2023-05-31 · in AVX512 intrinsics for JDK’s Arrays.sort methods

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AVX512 intrinsics for JDK’s Arrays.sort methods

story by mfiguiere · 2023-05-31 · 152 comments

Their is a detailed description of the new stack locking scheme in the PR here https://github.com/openjdk/jdk/pull/10907

comment by zorgmonkey · 2023-05-04 · in JEP 450: Compact Object Headers

…((long) upTo) - from + last; I would think it just takes less than 1 ms on first execution. https://github.com/openjdk/jdk/blob/caa841d9a52352a975394e55...

comment by alfu · 2023-04-15 · in How many floating-point numbers are in the interval [0,1]? (2017)

…be dispelled. OpenJDK is Java, and is open source under GPL. https://en.wikipedia.org/wiki/OpenJDK https://github.com/openjdk/jdk/blob/master/LICENSE

comment by jjav · 2023-04-12 · in Virtual Threads Arrive in JDK 21, Ushering a New Era of Concurrency

…have occurred before `ApplicationShutdownHooks.add` has been called so there is no publish problem. https://github.com/openjdk/jdk/blob/2fa09333ef0ac2dc1e44292f8d45d4571cb22cca/src/java.base/share/classes/java/lang/Runtime.java#L69…

comment by benmmurphy · 2023-03-29 · in Writing a Profiler in 240 lines of pure Java

…are these "interrupts" just the underlying syscall returning EINTR or something Java-specific? [1]: https://github.com/openjdk/jdk/blame/c313e1ac7b3305b1c012755... [2]: https://stackoverflow.com/questions/1161297/ --- Edit: marginalia_nu's…

comment by Arnavion · 2023-03-12 · in Don't Share Java FileChannels

…I don't agree it would create more boiler plate To get concrete again, I consider this boilerplate: https://github.com/openjdk/jdk/blob/9fc518ff8cadbbb731a016d8... https://github.com/openjdk/jdk/blob/9fc518ff8cadbbb731a016d8... And this is…

comment by MaulingMonkey · 2023-03-01 · in Make JDK source code UTF-8

…and all sorts of edge cases That can be done in code too. Let's take something concrete like https://github.com/openjdk/jdk/blob/master/test/jdk/java/uti... : {JPY, Locale.forLanguageTag("ja-JP-u-rg-uszzzz"), "\uffe5"}, {JPY,…

comment by MaulingMonkey · 2023-03-01 · in Make JDK source code UTF-8

GPLv2 specifically https://github.com/openjdk/jdk/blob/jdk-21%2B9/LICENSE#L3 although Java is the most famous software I know of with the "CLASSPATH exception" https://github.com/openjdk/jdk/blob/jdk-21%2B9/LICENSE#L326 to avoid "linking"…

comment by mdaniel · 2023-02-13 · in Re-License Vaultwarden to AGPLv3

…[1] and his PR's [2]. [1] https://mail.openjdk.org/pipermail/amber-dev/2023-January/th... [2] https://github.com/openjdk/jdk/pulls?q=is%3Apr+is%3Aopen+arc...

comment by carimura · 2023-01-23 · in JEP draft: No longer require super() and this() to appear first in a constructor

https://github.com/openjdk/jdk/blob/master/LICENSE

comment by jbellis · 2023-01-01 · in Java is in decline, and there's data to prove it

…library as part of the JVM (but part of the JDK), then the JVM is written mostly in C++. [0]: https://github.com/openjdk/jdk/tree/master/src/hotspot

comment by fathyb · 2022-12-21 · in OpenJDK Proposes Project Galahad to Merge GraalVM Native Compilation

…the whole JDK, not just the VM): Java 75.1% C++ 13.4% C 7.4% Assembly 2.3% Objective-C 0.4% [1] https://github.com/openjdk/jdk

comment by kasperni · 2022-12-21 · in OpenJDK Proposes Project Galahad to Merge GraalVM Native Compilation

To add to your question, assuming the tooling at github is ok, it has ~20% as c/c++ for https://github.com/openjdk/jdk . I would think most of that would be concentrated in the hotspot code, but I don't know. Would be delighted to know…

comment by taeric · 2022-12-21 · in OpenJDK Proposes Project Galahad to Merge GraalVM Native Compilation

…bit hacking to convert between fp16 and Java floats. This API along with the intrinsification ( https://github.com/openjdk/jdk/pull/10500 ) will mean I can throw away that code and replace it with something that performs correctly and is…

comment by craigacp · 2022-10-13 · in JDK 20 will introduce float16 conversion methods

…keep them in an indexable array anyway. [1] in HotSpot they are instances of InstanceKlass: https://github.com/openjdk/jdk/blob/master/src/hotspot/share...

comment by twic · 2022-10-11 · in JEP draft: 64 bit object headers

…to be any for that issue.) [0] https://bugs.openjdk.org/browse/JDK-8277131?jql=issuetype%20... [1] https://github.com/openjdk/jdk/pull/8787

comment by Nzen · 2022-09-29 · in Virtual Threads: New Foundations for High-Scale Java Applications

…have to forget about jpackage and redo it all with something like Packr [2] and Wix# [3]... [1] https://github.com/openjdk/jdk/blob/fe45835f7cebfccd4544ae19... [2] https://github.com/libgdx/packr [3] https://github.com/oleg-shilo/wixsharp

comment by ptx · 2022-09-29 · in Paving the on-ramp to Java

…seriously, if you want to learn about this, one place is to look at OpenJDK's sources. E.g. here: https://github.com/openjdk/jdk/blob/master/src/java.base/sha... which calls: https://github.com/openjdk/jdk/blob/17283cfe4c697e2118f19992...…

comment by amenghra · 2022-09-01 · in Falsehoods programmers believe about email

…For Java, https://docs.oracle.com/en/java/javase/18/docs/specs/jni/des... https://github.com/openjdk/jdk/blob/master/src/java.base/sha... And as bonus since you didn't ask for it, Eiffel https://www.eiffel.org/doc/solutions/CECIL_-_

comment by pjmlp · 2022-07-26 · in Treadmill garbage collector by H. Baker

…that wasn't done, and using the built in logger was slow enough to have measurable impact . See https://github.com/openjdk/jdk/blob/6765f902505fbdd02f25b599... at the bottom.

comment by hyperman1 · 2022-07-20 · in Log4j: The pain just keeps going

…of but you don't "just" implement virtual threads. The PR to do it in HotSpot is notoriously huge: https://github.com/openjdk/jdk/pull/8166 1,140 files, (+98,553 −9,862 LOC) and those lines of code are mostly horribly fiddly low level…

comment by mike_hearn · 2022-05-03 · in JEP proposed to target JDK 19: 425: Virtual Threads (Preview)

…- we never delete them. * Events are associated with a thread for the lifetime of the thread. */ https://github.com/openjdk/jdk/blob/c4c76e2f34f7e709f8b3c960... // ParkEvents are type-stable and immortal. // // Lifecycle: Once a ParkEvent…

comment by xxs · 2022-04-25 · in Chris Lattner on garbage collection vs. Automatic Reference Counting (2017)

…mechanism, however relying on the GC to perform resource management is a terrible practice. [0]: https://github.com/openjdk/jdk/blob/master/src/java.base/sha...

comment by xxs · 2022-04-24 · in Chris Lattner on garbage collection vs. Automatic Reference Counting (2017)

The fix for OpenJDK (authored on Jan. 4th 22): https://github.com/openjdk/jdk/blob/e2f8ce9c3ff4518e070960ba...

comment by bertman · 2022-04-20 · in Psychic Signatures in Java

It's easy to make this mistake, still: https://github.com/openjdk/jdk/blob/722d639fad2e4fc6eb2aabd4...

comment by __float · 2022-03-22 · in Java 18 / JDK 18: General Availability

…it happens in core Java libraries themselves: https://bugs.openjdk.java.net/browse/JDK-8274779 https://github.com/openjdk/jdk/blob/722d639fad2e4fc6eb2aabd4...

comment by __float · 2022-03-22 · in Java 18 / JDK 18: General Availability

…co. are great reads, and very well commented. See the source of `ConcurrentHashMap` for example: https://github.com/openjdk/jdk/blob/master/src/java.base/sha...

comment by ibraheemdev · 2022-03-22 · in Ask HN: Codebases with great, easy to read code?

…class from the Java standard library. Looking at the implementation here: https://github.com/openjdk/jdk/blob/4f607f2adac3798c16a62e90... If the requested directory name has certain "inappropriate" characters in it, it'll encode it

comment by rianmcguire · 2021-12-28 · in Ask HN: Is this weird folder name indication of attempted log4shell attack?