[Analyzer][StreamChecker] Introduction of stream error handling.

Authored by balazske on Apr 7 2020, 11:52 PM.


[Analyzer][StreamChecker] Introduction of stream error handling.

Store the error flags (EOF or error) of a stream.
Support the functions feof, ferror, clearerr.
Added a test checker for setting the error flags.

Reviewers: Szelethus, NoQ, Charusso, baloghadamsoftware, xazax.hun

Reviewed By: Szelethus

Subscribers: steakhal, ASDenysPetrov, rnkovacs, xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, Szelethus, donat.nagy, dkrupp, gamesh411, Charusso, martong, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D75682