Good day I have been doing a little kernel following some repositories of GitHub, videos and wikis, and I have found a topic that leaves me with doubts, the theme is the global constructors. Suppose I write a program in c, for the user space, for my code to run I must have the main function int main() { /*Code*/} The gcc compiler searches for this function to run my program, but before that happens, I can use the global constructors and write a code that runs before the main function, but in the case of writing a kernel, why do I need to run lines of code before the kernel is executed ?, I understand that when writing a kernel there is no main function and that it is disabled to indicate it to the compiler. In the Linux kernel are there global constructors? If so, what things are executed before starting the kernel? att: cristian vargas.