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Languages & runtimes · #c
Learn how C11’s _Generic keyword lets you write a single, type‑safe macro that expands to the correct abs‑family function for int, long, float, or double, with zero runtime cost.
Stop relying on member order in C structs. Designated initializers (.member = value) let you name fields at compile time, reducing bugs and improving readability.
Learn how to implement a high-throughput circular buffer in C using power-of-two masking and atomic indices to achieve O(1) performance without dynamic memory allocation.
Speed up your C memory copy by using the C99 <code>restrict</code> keyword. Learn how it works, see a concrete example, understand trade‑offs, and validate the performance gains in a few steps.
Identifying performance bottlenecks in C programs often starts with selecting appropriate measurement tools—software timers, profilers like gprof or perf, or hardware counters exposed via PAPI. The goal is to measure execution time, instruction counts, cache misses, and branch mispredictions to pinpoint inefficient code paths. Constraints include the target
When a C program that calculates concrete compressive strength crashes with a segmentation fault, what systematic steps can be taken to locate the source of the fault? Consider techniques such as reproducing the crash under a debugger, examining core dumps, checking pointer usage and array bounds, and validating input data. How can one isolate whether the is
In C (ISO/IEC 9899), pointer arithmetic is permitted within the bounds of an array, including one element past the end. However, dereferencing a pointer that has moved beyond this boundary triggers Undefined Behavior (UB). A specific concern arises when compiler optimizations (such as -O2 or -O3 ) are applied. Because the compiler assumes UB never occurs, it
C leaves the order in which function arguments and operands of most operators are evaluated unspecified, and it leaves sequencing of side effects to sequence points. This documented unspecified behavior means the same source can be legal yet produce different observable results across implementations and optimization levels. The goal is to characterize the p
In C development, calling free() on a pointer that has already been deallocated results in undefined behavior according to ISO/IEC 9899. While modern allocators like glibc attempt to mitigate this by monitoring chunk metadata, the specific response to corruption varies across different standard library implementations. When a double-free is detected, the run