[Flang] GENERIC INTERFACE: BINC(C) attribute not propagate to the generic name that is the same as the specific name that has the BIND(C) attribute.

[DanielCChen]

Consider the following code:

  MODULE M
  USE ISO_C_BINDING

  INTERFACE ExtFun
    FUNCTION ExtFun() BIND(C)
    IMPORT
      INTEGER(C_INT) :: ExtFun
    END FUNCTION
  END INTERFACE

  END MODULE

  PROGRAM MAIN
  USE M
  PROCEDURE(ExtFun), BIND(C), POINTER :: PExtFun
  END

Flang currently issues an error as:

: error: An interface name with BIND attribute must be specified if the BIND attribute is specified in a procedure declaration statement
    PROCEDURE(ExtFun), BIND(C), POINTER :: PExtFun
                                           ^^^^^^^

It passes if I remove the generic name. The BIND(C) attribute seems missing from both the generic and specific symbol in the dump.

[llvmbot]

@llvm/issue-subscribers-flang-frontend

Author: Daniel Chen (DanielCChen)

Consider the following code: ``` MODULE M USE ISO_C_BINDING

INTERFACE ExtFun
FUNCTION ExtFun() BIND(C)
IMPORT
INTEGER(C_INT) :: ExtFun
END FUNCTION
END INTERFACE

END MODULE

PROGRAM MAIN
USE M
PROCEDURE(ExtFun), BIND(C), POINTER :: PExtFun
END

Flang currently issues an error as:

: error: An interface name with BIND attribute must be specified if the BIND attribute is specified in a procedure declaration statement
PROCEDURE(ExtFun), BIND(C), POINTER :: PExtFun
^^^^^^^

It passes if I remove the generic name. The `BIND(C)` attribute seems missing from both the generic and specific symbol in the dump.
</details>

[llvmbot]

@llvm/issue-subscribers-bug

Author: Daniel Chen (DanielCChen)

Consider the following code: ``` MODULE M USE ISO_C_BINDING

INTERFACE ExtFun
FUNCTION ExtFun() BIND(C)
IMPORT
INTEGER(C_INT) :: ExtFun
END FUNCTION
END INTERFACE

END MODULE

PROGRAM MAIN
USE M
PROCEDURE(ExtFun), BIND(C), POINTER :: PExtFun
END

Flang currently issues an error as:

: error: An interface name with BIND attribute must be specified if the BIND attribute is specified in a procedure declaration statement
PROCEDURE(ExtFun), BIND(C), POINTER :: PExtFun
^^^^^^^

It passes if I remove the generic name. The `BIND(C)` attribute seems missing from both the generic and specific symbol in the dump.
</details>

[klausler]

#82837

[DanielCChen]

I have verified PR #82837 has fixed the reproducer and the original test case.
Thanks for the quick fix! @klausler