One of the common defenses of the abuse of “undefined behavior” by C compilers, and the stupid aliasing rules in the standard is that those things are necessary for optimizations, like using vector operations. Here’s an example of where gcc
Torvalds on aliasing
See also PLOS article, pointer alias in C and remarks on the purpose of C. From: LKML From Linus Torvalds <> Date Tue, 5 Jun 2018 10:30:21 -0700 Subject Re: [GIT PULL] Device properties framework update for v4.18-rc1 On Mon, Jun
Pointer alias analysis in C
Perhaps there is some reason to provide a mechanism for asserting, in a particular patch of code, that the compiler is free to make optimistic assumptions about the kinds of aliasing that can occur. I don’t know any acceptable way of
Judea Pearl’s mysterious claim
Pearl: Of course, but you cannot see this noble aspiration in scientific equations. The language of algebra is symmetric: If x tells us about y, then y tells us about x. I’m talking about deterministic relationships. There’s no way to write in mathematics a simple fact—for example,
Depressing and faintly terrifying days for the C standard
C STANDARD UNDEFINED BEHAVIOR VERSUS WITTGENSTEIN 1. DEPRESSING AND FAINTLY TERRIFYING Chris Lattner, the architect of the Clang/LLVM C compiler explained the effects of the C standard’s “undefined behavior (UB): UB is an inseperable part of C programming, […] this
victor.yodaiken@gmail.com
See also: Damore’s Defenders. Scott Aaronson is a distinguished professor of computer science at the University of Texas. I ran into his blog a while back, when someone sent me to his muddled defense of Damore and the Google Memo
Clock Sync in Finance and Beyond.
A FSMLabs whitepaper. [gview file=”https://www.yodaiken.com/wp-content/uploads/2018/05/financeandbeyond.pdf”]
Trees in informal methods
What’s a tree? First define a sequence or length n> 0 as a total map s: {1,.. n}→ X. Let Nil be the empty sequence. If s is a sequence of length n, and x is an element, then u
Linked lists
What’s a linked list? Let V be a set of values and A be a set of “addresses”. Say a map f is a “linked list element” compatible with values V and addresses A if and only if f(value)∈ V
New and or notable.
My new favorite line: “My good sir, I worry that your groundbreaking treatise will go overlooked here on Twitter” This is a great essay on programming: Operant Conditioning by Software Bugs. This is a good point on mathematics versus the