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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

Semantic Commit Messages

See how a minor change to your commit message style can make you a better programmer.

Format: <type>(<scope>): <subject>

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Useful Pandas Snippets

A personal diary of DataFrame munging over the years.

Data Types and Conversion

Convert Series datatype to numeric (will error if column has non-numeric values)
(h/t @makmanalp)

	<#
	.EXAMPLE
	llm "what is the capital of spain" -provider openai

	.EXAMPLE
	llm "what is the capital of spain" -provider anthropic

	.EXAMPLE
	llm "what is the capital of spain" -provider gemini
	#>

	#!/usr/local/plan9/bin/rc

	. 9.rc
	. $PLAN9/lib/acme.rc

	fn convert {
	awk -F'=' '
	$1 == "indent_style" {
	print "Spaces", ($2 == "space") ? "on" : "off"
	}

	// Run GOOGLE CHROME - WORKING AS OF DEC 26 2023
	// Please @ me in the comments if this stops working, I will try to get it working again within the month

	// INSTRUCTIONS
	// 1. Open Instagram in Chrome
	// 2. Click on "FOLLOWING" on your Instagram profile
	// 3. Open developer tools by right clicking on the page and clicking "INSPECT"
	// 4. Copy the code below and paste in the developer tools console and press enter to run
	// 5. Script will not run if tab is navigated away from, minimized of unfocused (It is recommended to open a new chrome window or push tab to the side and let script run in background)

	{
	"estados": [
	{
	"sigla": "AC",
	"nome": "Acre",
	"cidades": [
	"Acrelândia",
	"Assis Brasil",
	"Brasiléia",
	"Bujari",


	--[[
	Email Password Recovery module.
	Using this module, you can request a password reset link from the game using 'recover_email_password' RPC.
	--]]

	local nk = require("nakama")

	local HTTPS_PREFIX = "https://"
	local MAILGUN_API_BASE_URL = "api.mailgun.net/v3"

	#!/bin/sh
	if [ "$(whoami)" != "root" ]; then
	echo "Please run this script as root."
	exit
	fi
	printf "This script will\n\n- Remove Snap\n- Install the deb version of Firefox\n- Install Flatpak\n- Optionally replace Ubuntu Desktop with GNOME\n\n"
	read -p "Continue? (Y/n) " start_prompt
	case $start_prompt in
	[nN] \| [nN][oO] )
	exit

	// quick bit of code to move displays to specific locations in C#

	[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)]
	public struct DEVMODE
	{
	[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)]
	public string dmDeviceName;

	public short dmSpecVersion;
	public short dmDriverVersion;