f18's module files are Fortran with a leading header comment containing
the module file format version and a hash of the following contents.
This hash is currently used only to protect module files against
corruption and truncation.
Extend the use of these hashes to catch or avoid some error cases. When
one module file depends upon another, note its hash in additional module
file header comments. This allows the compiler to detect when the module
dependency is on a module file that has been updated. Further, it allows
the compiler to find the right module file dependency when the same
module file name appears in multiple directories on the module search
path.
The order in which module files are written, when multiple modules
appear in a source file, is such that every dependency is written before
the module(s) that depend upon it, so that their hashes are known.
A warning is emitted when a module file is not the first hit on the
module file search path.
Further work is needed to add a compiler option that emits (larger)
stand-alone module files that incorporate copies of their dependencies
rather than relying on search paths. This will be desirable for
application libraries that want to ship only "top-level" module files
without needing to include their dependencies.
Another future work item would be to admit multiple modules in the same
compilation with the same name if they have distinct hashes.
This is an ongoing series of commits that are reformatting our
Python code. This catches the last of the python files to
reformat. Since they where so few I bunched them together.
Reformatting is done with `black`.
If you end up having problems merging this commit because you
have made changes to a python file, the best way to handle that
is to run git checkout --ours <yourfile> and then reformat it
with black.
If you run into any problems, post to discourse about it and
we will try to help.
RFC Thread below:
https://discourse.llvm.org/t/rfc-document-and-standardize-python-code-style
Reviewed By: jhenderson, #libc, Mordante, sivachandra
Differential Revision: https://reviews.llvm.org/D150784
To enable Flang testing on Windows, shell scripts have
to be ported to Python. The following changes have been made:
"test_modfile.sh" has been ported to Python, and
the relevant tests relying on it.
Reviewed By: Meinersbur
Differential Revision: https://reviews.llvm.org/D107956
