tree c2ea107e61d5f74e9369aac743ceddade6207fdc
parent db8ab789ea49c61ecc2e9f5b2d332ff279184a2d
author Andrzej Warzynski <andrzej.warzynski@arm.com> 1612256853 +0000
committer Copybara-Service <copybara-worker@google.com> 1612516966 -0800

[flang][driver] Disallow non-existent input files in the frontend driver

This patch adds a check that verifies that the input file used when
calling the frontend driver (i.e. `flang-new -fc1`) actually exists.
This was not required for the compiler driver, `flang-new`, as that's
already handled in libclangDriver.

Once all input/output file management is moved to the driver, we should
also check that for input from `stdin` the corresponding file descriptor
was successfully acquired.

This patch also makes sure that the default action in the frontend is
`ParseSyntaxOnly`. This is consistent with Clang. Before this change
`flang-new -fc1` would do nothing, which makes testing changes like the
one introduced here a bit tricky.

Reviewed By: SouraVX

Differential Revision: https://reviews.llvm.org/D95127

GitOrigin-RevId: 760e6c4ce58324856d8f105b37bb974564e0f170