To accomplish this, this patch creates an optional list of environment
variable default values to be set by the runtime to allow directly using
the existing runtime implementation of FORT_CONVERT for I/O conversions.
Move the closure of the subset of flang/runtime/*.h header files that
are referenced by source files outside flang/runtime (apart from unit tests)
into a new directory (flang/include/flang/Runtime) so that relative
include paths into ../runtime need not be used.
flang/runtime/pgmath.h.inc is moved to flang/include/flang/Evaluate;
it's not used by the runtime.
Differential Revision: https://reviews.llvm.org/D109107
As `external-hello-world` is not really a test, I am moving it from
`flang/unittest/Runtime` to `flang/examples` (it makes a lot of sense as
an example). I've not modified the source code (apart from adjusting the
include paths).
Differential Revision: https://reviews.llvm.org/D104320
Jonathon Penix