[clang-tidy] misc-include-cleaner does not handle signal.h properly

[UtkarshVerma]

I have this repo (dwmblocks-async) which generates a few errors when I run clang-tidy.

$ clang-tidy include/signal-handler.h
551 warnings generated.
/home/subaru/.local/src/dwmblocks/include/signal-handler.h:4:1: warning: included header signal.h is not used directly [misc-include-cleaner]
    4 | #include <signal.h>  // IWYU pragma: private; include <bits/types/sigset_t>
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    5 |
/home/subaru/.local/src/dwmblocks/include/signal-handler.h:9:9: warning: no header providing "sigset_t" is directly included [misc-include-cleaner]
    4 | #include <signal.h>  // IWYU pragma: private; include <bits/types/sigset_t>
    5 |
    6 | #include "block.h"
    7 | #include "timer.h"
    8 |
    9 | typedef sigset_t signal_set;
      |         ^
Suppressed 550 warnings (549 in non-user code, 1 NOLINT).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.

I tried doing adding the appropriate IWYU pragmas to signal-handler.h.

https://github.com/UtkarshVerma/dwmblocks-async/blob/main/include/signal-handler.h

#include <signal.h>  // IWYU pragma: private; include <bits/types/sigset_t>

But this doesn't seem to work. Am I doing something wrong?

[llvmbot]

@llvm/issue-subscribers-clang-include-cleaner

Author: Utkarsh Verma (UtkarshVerma)

I have this repo ([dwmblocks-async](https://github.com/UtkarshVerma/dwmblocks-async)) which generates a few errors when I run clang-tidy.

$ clang-tidy include/signal-handler.h
551 warnings generated.
/home/subaru/.local/src/dwmblocks/include/signal-handler.h:4:1: warning: included header signal.h is not used directly [misc-include-cleaner]
    4 | #include <signal.h>  // IWYU pragma: private; include <bits/types/sigset_t>
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    5 |
/home/subaru/.local/src/dwmblocks/include/signal-handler.h:9:9: warning: no header providing "sigset_t" is directly included [misc-include-cleaner]
    4 | #include <signal.h>  // IWYU pragma: private; include <bits/types/sigset_t>
    5 |
    6 | #include "block.h"
    7 | #include "timer.h"
    8 |
    9 | typedef sigset_t signal_set;
      |         ^
Suppressed 550 warnings (549 in non-user code, 1 NOLINT).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.

I tried doing adding the appropriate IWYU pragmas to signal-handler.h.

https://github.com/UtkarshVerma/dwmblocks-async/blob/main/include/signal-handler.h

#include <signal.h>  // IWYU pragma: private; include <bits/types/sigset_t>

But this doesn't seem to work. Am I doing something wrong?

[llvmbot]

@llvm/issue-subscribers-clang-tidy

Author: Utkarsh Verma (UtkarshVerma)

I have this repo ([dwmblocks-async](https://github.com/UtkarshVerma/dwmblocks-async)) which generates a few errors when I run clang-tidy.

$ clang-tidy include/signal-handler.h
551 warnings generated.
/home/subaru/.local/src/dwmblocks/include/signal-handler.h:4:1: warning: included header signal.h is not used directly [misc-include-cleaner]
    4 | #include <signal.h>  // IWYU pragma: private; include <bits/types/sigset_t>
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    5 |
/home/subaru/.local/src/dwmblocks/include/signal-handler.h:9:9: warning: no header providing "sigset_t" is directly included [misc-include-cleaner]
    4 | #include <signal.h>  // IWYU pragma: private; include <bits/types/sigset_t>
    5 |
    6 | #include "block.h"
    7 | #include "timer.h"
    8 |
    9 | typedef sigset_t signal_set;
      |         ^
Suppressed 550 warnings (549 in non-user code, 1 NOLINT).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.

I tried doing adding the appropriate IWYU pragmas to signal-handler.h.

https://github.com/UtkarshVerma/dwmblocks-async/blob/main/include/signal-handler.h

#include <signal.h>  // IWYU pragma: private; include <bits/types/sigset_t>

But this doesn't seem to work. Am I doing something wrong?

[carlosgalvezp]

You shouldn't need any pragma, since sigset_t is defined in signal.h. Certainly it should not be pragma private.

It sounds like a bug in the check. Maybe it does not have the correct mapping registered for this symbol.

[UtkarshVerma]

Please let me know if you want me to check anything. The source code is public so it should be easily reproducible.

[carlosgalvezp]

I rephrased the bug title and created a minimal example here:

https://godbolt.org/z/9hqv1on16