CWD is queried in clang driver and passed to clang cc1 via flags when
needed. Respect the cc1 flags and do not repeated checking current
working directory in CodeGen.
A significant number of our tests in C accidentally use functions
without prototypes. This patch converts the function signatures to have
a prototype for the situations where the test is not specific to K&R C
declarations. e.g.,
void func();
becomes
void func(void);
This is the eighth batch of tests being updated (there are a
significant number of other tests left to be updated).
These flags affect coverage mapping (-fcoverage-mapping), not
-fprofile-[instr-]generate so it makes more sense to use the
-fcoverage-* prefix.
Differential Revision: https://reviews.llvm.org/D97434
