tree 5e7134145c9f3ae45dbd598ee855662fff50ef17
parent 0852fa8df2cf1ef97fb50885dbcb43f2a7fc9b31
author Andrzej Warzynski <andrzej.warzynski@arm.com> 1612455822 +0000
committer Copybara-Service <copybara-worker@google.com> 1612517018 -0800

[flang][driver] Fix reading from stdin when using `-test-io`

This patch adds logic in the InputOutputTestAction frontend action for
reading input from stdin. Without this patch the following fails:
```
    flang-new -fc1 -test-io -
```

The implementation of `InputOutputTestAction` is cleaned-up and a test
for reading from stdin is added.

Note that there's a difference between `-test-io` and e.g. `-E` in terms
of file I/O. The frontend action for the former handles all file I/O on
it's own. Conversely, the action corresponding to -E relies on the
prescanner API to handle this.

Currently we can't test reading from stdin for `flang-new -`. In this
case `libclangDriver` assumes `-x -c`. This in turn leads to `flang-new
-cc1`, which is not supported.

GitOrigin-RevId: ba000628bdbddfe1ec37da9aa7aa2d19f03cb3a4