Monthly Archives: March 2026

Learn Something Old Every Day, Part XVIII: How Does FPU Detection Work?

Posted on March 28, 2026 by Michal Necasek

This post ended up being much longer than originally intended because halfway into writing it, I found that 286 and later CPUs don’t behave the way I had assumed they would… While investigating a bug related to a program using … Continue reading →

Posted in 286, 8086/8088, x86, x87 | 34 Comments

Bitfield Pitfalls

Posted on March 20, 2026 by Michal Necasek

Some time ago I ran into a bug that had been dormant for some time. The problem involved expressions where one of the operands is a bit-field. To demonstrate the problem, I will present a reduced example: #include <stdio.h> #include … Continue reading →

Posted in C, Development, Standards | 4 Comments