With modern architectures having a thread pointer and language supporting
thread locals, there is no reason to use a function intermediary to access
the thread local errno value.
The entrypoint corresponding to errno has been replaced with an object
library as there is no formal entrypoint for errno anymore.
Reviewed By: jeffbailey, michaelrj
Differential Revision: https://reviews.llvm.org/D120920
Also moved most of the common type definitions from libc/spec/stdc.td
to libc/spec/spec.td so that they can be used to list functions in llvm_libc_ext.td.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D89436
Siva Chandra Reddy