llvm-project

8ed6058b - [libc] Add a placeholder for POSIX sys/shm.h header (#237283)

[libc] Add a placeholder for POSIX sys/shm.h header (#237283) `<sys/shm.h>` is a POSIX header providing the functionality to use the XSI shared memory facility. Provide this header in LLVM-libc, and populate a handful of types and macros as required by the latest POSIX spec in https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sys_shm.h.html: * forward-include `<sys/ipc.h>` header * provide type definitions for several types: pid_t, size_t, time_t, intptr_t. Also define shmatt_t. * Define a few `SHM_*` symbolic constants used in `schmat` flags. No functions provided in the header yet - those would be added in subsequent PRs.