The article "Into the depths of C: Elaborating the de facto standards" (2016) explores the practical, widely adopted conventions and behaviors in C programming that are not formally standardized but are universally relied upon by developers and compilers. It examines how these de facto standards emerge from real-world usage, toolchain behavior, and historical precedent, often filling gaps left by the official C standard. The piece highlights the tension between formal specification and practical implementation, noting that many critical aspects of C programming—such as memory layout, calling conventions, and undefined behavior handling—are governed by community consensus rather than ISO/IEC 9899.

By analyzing compiler behavior, popular libraries, and legacy codebases, the author illustrates how these unwritten rules shape portability, performance, and reliability in C systems. The discussion underscores the importance of understanding these norms for writing robust, maintainable low-level code, especially in embedded systems, operating systems, and performance-critical applications where adherence to de facto practices often outweighs strict standard compliance.