Suppose I am writing a fixed-size array class of runtime size, somewhat equivalent to Rust's Box<[T]> in order to save the space of tracking cap ...

Let's say I have this code: All I want is to interpret the bits from the bits variable as a float. I came to understand that this is called "type p ...

I saw this cast: But when casting, the wrong number gets into the float. Moreover, if I use a static cast, then it is cast correctly. Why is th ...

I've recently read about type punning and strict aliasing in C. I believe the following attempt at type-punning violates the strict aliasing rule: ...

I have the following sample code: Under x86-64 clang 13.0.1, the code compiles as expected. Under x86-64 clang 14.0.0 or 15, the output is merely ...

I know. I know. This question has been answered before, but I have a slightly different and a bit more specific question. My goal is, as the title su ...

A relative question, but I want a solution without any run-time overhead. (So constructing a new pair or using std::variant are not the answers) Du ...

Consider this code: Is this code valid? Invocations: Which compiler is correct? ...

Some languages (like Rust, Zig, GLSL, HLSL) have built-in methods to build a floating type from bits supplied as an unsigned integer. However C and C+ ...

Which way in below tests is the most preferred in terms of dealing with undefined behavior, auto-vectorization (for struct of arrays) and portability ...

Is bit_casting arrays of one type to another needed to avoid UB? For example, I have a function Do I need to use bit_cast instead? Or a use memc ...

Upon decompiling various programs (which I do not have the source for), I have found some interesting sequences of code. A program has a c-string (str ...

I am maintaining an old code base, that is using a union of an integer type with a bit-field struct for type-punning. My compiler is VS2017. As an exa ...

Type-punning through unions has defined behaviour in C: Given via a footnote in the C Standard: If the member used to read the contents of a un ...

For example, can this cause unpredictable results on a platform where, unsigned and float are both 32-bit a pointer has a fixed size for all ...

Say I'm working on a library called libModern. This library uses a legacy C library, called libLegacy, as an implementation strategy. libLegacy's inte ...

Is it possible to implement something similar to C++20's std::bit_cast in C? It would be a lot more convenient than using union or casting pointers to ...

I need to process data that is given to me as a char buffer where the actual structure of the data depends on the values of some of its fields. More ...

I have to following issue: I'm using this king of structures to access the same variable but with different size. In this way I can access to a 8bi ...

This code to read a uint64_t as two uint32_t is UB due to the strict aliasing rule: Likewise, this code to write the upper and lower part of an uin ...