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@staltz
staltz / introrx.md
Last active May 6, 2024 01:44
The introduction to Reactive Programming you've been missing
@piscisaureus
piscisaureus / pr.md
Created August 13, 2012 16:12
Checkout github pull requests locally

Locate the section for your github remote in the .git/config file. It looks like this:

[remote "origin"]
	fetch = +refs/heads/*:refs/remotes/origin/*
	url = git@github.com:joyent/node.git

Now add the line fetch = +refs/pull/*/head:refs/remotes/origin/pr/* to this section. Obviously, change the github url to match your project's URL. It ends up looking like this:

@shafik
shafik / WhatIsStrictAliasingAndWhyDoWeCare.md
Last active May 2, 2024 15:08
What is Strict Aliasing and Why do we Care?

What is the Strict Aliasing Rule and Why do we care?

(OR Type Punning, Undefined Behavior and Alignment, Oh My!)

What is strict aliasing? First we will describe what is aliasing and then we can learn what being strict about it means.

In C and C++ aliasing has to do with what expression types we are allowed to access stored values through. In both C and C++ the standard specifies which expression types are allowed to alias which types. The compiler and optimizer are allowed to assume we follow the aliasing rules strictly, hence the term strict aliasing rule. If we attempt to access a value using a type not allowed it is classified as undefined behavior(UB). Once we have undefined behavior all bets are off, the results of our program are no longer reliable.

Unfortunately with strict aliasing violations, we will often obtain the results we expect, leaving the possibility the a future version of a compiler with a new optimization will break code we th

@aras-p
aras-p / preprocessor_fun.h
Last active April 28, 2024 15:25
Things to commit just before leaving your job
// Just before switching jobs:
// Add one of these.
// Preferably into the same commit where you do a large merge.
//
// This started as a tweet with a joke of "C++ pro-tip: #define private public",
// and then it quickly escalated into more and more evil suggestions.
// I've tried to capture interesting suggestions here.
//
// Contributors: @r2d2rigo, @joeldevahl, @msinilo, @_Humus_,
// @YuriyODonnell, @rygorous, @cmuratori, @mike_acton, @grumpygiant,
@bishboria
bishboria / springer-free-maths-books.md
Last active April 25, 2024 06:27
Springer made a bunch of books available for free, these were the direct links
This work, excluding the Arch Linux logo, is made available under CC0: https://creativecommons.org/publicdomain/zero/1.0/
@ErikAugust
ErikAugust / spectre.c
Last active April 15, 2024 13:55
Spectre example code
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#ifdef _MSC_VER
#include <intrin.h> /* for rdtscp and clflush */
#pragma optimize("gt",on)
#else
#include <x86intrin.h> /* for rdtscp and clflush */
#endif
@atoponce
atoponce / rates.md
Last active April 12, 2024 21:23
Verifiable brute force strength rates across different projects

Verifiable brute force strength

Below are table of various projects that can completely exhaust n-bits of keyspace. In other words, counting completely and fully from 0 to 2ⁿ-1.

This Gist implies no discussion about how this is relevant to quantum computing using Grover's algorithm, meet-in-the-middle or birthday attacks, or anything of the like. It's strictly a Gist about raw speed, measuring the result in bits.

If you know of other noteworthy and verifiable brute force searching projects,

@Earnestly
Earnestly / c99_ub_list.rst
Last active March 29, 2024 03:52
C99 List of Undefined Behavior (193 Cases)

C99 List of Undefined Behavior

From N1256: (See http://port70.net/~nsz/c/c99/n1256.html#J.2)

  • A "shall" or "shall not" requirement that appears outside of a constraint is violated (clause 4).
  • A nonempty source file does not end in a new-line character which is not immediately preceded by a backslash character or ends in a partial preprocessing token or comment (5.1.1.2).
  • Token concatenation produces a character sequence matching the syntax of a universal character name (5.1.1.2).
  • A program in a hosted environment does not define a function named main using one of the specified forms (5.1.2.2.1).
  • A character not in the basic source character set is encountered in a source file, except in an identifier, a character constant, a string literal, a header name, a comment, or a preprocessing token that is never converted to a token (5.2.1).
  • An identifier, comment, string literal, character constant, or header name contains an invalid multibyte character or does not
@ddevault
ddevault / Makefile
Last active February 20, 2024 14:17
Tiny Wayland compositor
WAYLAND_PROTOCOLS=/usr/share/wayland-protocols
# wayland-scanner is a tool which generates C headers and rigging for Wayland
# protocols, which are specified in XML. wlroots requires you to rig these up
# to your build system yourself and provide them in the include path.
xdg-shell-protocol.h:
wayland-scanner server-header \
$(WAYLAND_PROTOCOLS)/stable/xdg-shell/xdg-shell.xml $@
xdg-shell-protocol.c: xdg-shell-protocol.h