King found that currently there are more than four thousand "FIXME" comments within the Linux 4.4 kernel source code. After becoming curious, he found almost 4,500 "TODO" comments in the kernel source code as well.
Running some analytics on the kernel code-base about FIXME and TODO comments, he found there is certainly an upward trend with the frequency of such comments in the kernel code. However, at the same time, the Linux kernel size continues increasing.
When factoring the size of the Linux kernel source code, he found the number of FIXME comments in the kernel are dropping while TODO comments are increasing. If you are curious about these light Linux kernel FIXME/TODO statistics, visit Colin's blog.