bazel: Include checking fails on windows for generated C header files (undeclared inclusion(s))

Description of the problem / feature request:

Include checking fails on windows for generated C/CPP header files. (the compilation is OK, but when Bazel checks the files afterwards, the header file is not recognized.)

Feature requests: what underlying problem are you trying to solve with this feature?

The include checking fails in CppCompileAction.java, in validateInclusions.

The line which is supposed to say the header file is ok is (around line 807):

if (allowedIncludes.contains(input)) {
  continue;
}

The problem is that the artifact execroot differs on Windows and Linux for all generated files: Edit: There seem to be a more intricate problem then just “all generated files”. It might have something to do with circular dependencies? I am trying to get a minimal example rolling.

Linux:

• my/generated/header/path/myheader.h

Windows:

• bazel-out/x64_windows-fastbuild/bin/my/generated/header/path/myheader.h

which causes the include check to fail.

A quick fix would be to add yet another check:

// Problem on windows with generated headers.
for (Artifact artifact : allowedIncludes) {
  if (artifact.getRootRelativePath().toString().equals(input.getExecPath().toString()))
  {
     continue checking;
  }
}

But it is not the clean way forward.

Bugs: what’s the simplest, easiest way to reproduce this bug? Please provide a minimal example if possible.

• Create a header-file with a Skylark rule (if gen-rule, set output_to_bindir =True).
• Include the file in a C file.
• Try to compile on windows.

Edit: The problem is more intricate than this, i am trying to create a minimal example.

What operating system are you running Bazel on?

Windows

What’s the output of bazel info release?

release 0.21.0

Have you found anything relevant by searching the web?

Might be the same cause as to #3828 and #6337

Any other information, logs, or outputs that you want to share?

No