Hackers' Pub

Syntax	Description	Examples
`"` keyword `"`	Finds the string within quotes, including spaces. Case-insensitive. (Escape quotes inside with `\"`)	`"Hackers' Pub"`
`from:` handle	Finds content written by the specified user.	`from:hongminhee` `from:hongminhee@hollo.social`
`lang:` ISO 639-1	Finds content written in the specified language.	`lang:en`
`#` tag	Finds content with the specified tag. Case-insensitive.	`#HackersPub`
condition condition	Finds content that satisfies both conditions on either side of the space (logical AND).	`"Hackers' Pub" lang:en`
condition `OR` condition	Finds content that satisfies at least one of the conditions on either side of the OR operator (logical OR).	`#HackersPub OR "Hackers' Pub" lang:en`
`(` condition `)`	Combines the operators within the parentheses first.	`(#HackersPub OR "Hackers' Pub" OR "Hackers Pub") lang:en`

matt godbolt @mattgodbolt@hachyderm.io

12/24/2025, 1:21:43 PM

Public

Day 24 of Advent of Compiler Optimisations!

A simple loop that sums integers from 0 to n. GCC cleverly unrolls it to process two numbers at once. But clang? The loop completely disappears—replaced by a few multiplies and shifts that compute the answer directly. How does it recognise this pattern and transform O(n) code into O(1)?

#AoCO2025

When compilers surprise you — Matt Godbolt’s blog

Sometimes compilers can surprise and delight even a jaded old engineer like me

xania.org

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