Syscalls required by glibc calls

Are there any lists compiled that provide a list of linux system calls used per function in a standard glibc build? For example, free() requires mmap, munmap, mprotect, prlimit64, and brk. If necessary I can figure this out by grepping the source code or some strace wizardry, but I don't want to reinvent the wheel. I've been searching the web for about a week with no avail, mostly just turning up info on system call wrappers. I am aware that officially there is no such certainty, but I know from practical experience that this info changes for most functions very rarely. I asked this on Stack Overflow, but this forum seems more appropriate, since I am looking for documentation (which may or may not exist). Thanks