Fun with Serial and Parallel Sum Reductions 121 implied HN points • 22 Feb 24 🔬 Science Mathematics Computer Science Algorithms Floating point arithmetic can be more complex than expected, especially due to limited mantissa bits, affecting the accuracy of calculations. Complaining about OpenMP reductions giving 'the wrong answer' is misguided; the issue likely existed in the serial code and is now being exposed. Changing the type of the accumulator to 'double' can help resolve issues with floating point arithmetic and accuracy during sum reductions.
Is Mixing OpenMP® Runtimes Safe? 0 implied HN points • 31 Oct 23 🕹 Technology Programming Compilers Mixing OpenMP runtimes in the same program can cause fatal issues. For non-offload codes, the LLVM runtime can provide the interfaces needed by GCC compiled OpenMP code. It's safer to link with the LLVM runtime only when dealing with OpenMP.