<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/156267>156267</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [Flang] No error checking for unseparated statement number and keyword in free form
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            flang:frontend
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          ohno-fj
      </td>
    </tr>
</table>

<pre>
    ```
Version of flang : 22.0.0(a5cf82c645245c4f6ed3dcc2178b8abfeed0f7d5)/AArch64
```

The attached program (`snf_inline_2904_4_2.f90`) is incorrect.
This program is `free form`, with no separation between `statement number` and `keyword`.

According to `Fortran Standard 2023: 6.3.2.2 Blank characters in free form`, a blank shall be used to separate names, constants, or labels from adjacent keywords, names, constants, or labels.

Thus, `10print` in this program requires a space between `10` and `print`.
Flang probably needs to detect programming errors during compilation.

The following are the test program, Flang, Gfortran and ifx compilation/execution result.

snf_inline_2904_4_2.f90:
```fortran
program minimal_example
 10print *, 'pass'

end program minimal_example
```

```
$ flang snf_inline_2904_4_2.f90; ./a.out
 pass
$
```

```
$ gfortran snf_inline_2904_4_2.f90
snf_inline_2904_4_2.f90:2:6:

    2 |   10print *, 'pass'
      |      1
Error: Non-numeric character in statement label at (1)
$
```

```
$ ifx snf_inline_2904_4_2.f90; ./a.out
 pass
$
```


</pre>
<img width="1" height="1" alt="" src="http://email.email.llvm.org/o/eJysVU2T2zYM_TX0BbMaGvqyDjooSd1bLu30ugORkMVdiXRJKrv77zuU5djZziY91OMZmxbwADy-B1MI5mSZW1F-EuWXHS1xdL51o3UPw9Oud_qtFZXc3rL7i30wzoIbYJjInkDkHSBmMpMCD1Sq4YCqKkosSlUMFetcK4X7-tAfqB-YtRxqXQpsBB67zquxKoTs7isI2f05MlCMpEbWcPbu5GkGgQdRyWCHR2MnY_kRG1k8Fo-YDc2aig2YAMYq5z2rmK1AJnwHMAFEJQfPDIPz85ryGV5MHME6CHwmTzHN1nN8YbYpOkSKPLONYJe5Zy8qCWR1evTMby_Oa1HJ7NJ1p5Tz2tgTRJcCjs5HTxb-iGQ1eQ0oMU90VVmeYYbwaSL7DGokTyqyT73D-_YI-jUqjDRN0DMsgXUqsPXLYGnmkEKVsyGSjevBeZio5ynA4N0MpJ9IpTG2rteYX2Rm18tY1t9FJffy7I2NiQRjId6T6_nvxXgOQBDOpPiexL28o-2KkNCPq4LO3vXUT29gmXVIs2mOrOIVe06UsvfOB9CLTyfl5rOZ1tvKbpIZ3DS5l_ScPEMcGSKH7zBphrVg-vL7sF1O6soMr_eIAo_8ympZteA5LFPcinwkvry71_AGLWR3JWc21sw0PfIrzeeJhexgoxIEdiu5WJ8pBIH1pRLbm_D_nf3OLj8csdiM-WGznyATeKTMLTF1stZdE3-NfLrS9hH4zzhCkXfVxpXsAAAQRP0Z4KdkwPq6xKVQIbvfkhaSkb46-2CXmb1RNxslad5su0oZKGEf9mnt_MdJkyb-DwZ3us11kze043Zfl1XV7BHr3diWxYDcS1kwamoQcSBS1aHRB5X3dYE706LEUjZyL_dFLatMyn1eVw0dqCxV3qMoJM9kpmyavs2Z86edCWHhdl9WWNW7i4nXvY64SkLk3eCdjWy1QEzb3rcp96FfTkEUcjIhhhtaNHFa_xcurim_wFd38SGokdVzMtrgPCz2uos0vN-Xq7-2nfPDetstfmrHGM8hKQKPAo8nE8elz5SbBR5TF9vHw9m7J1ZR4HEdMAg8bjN-a_GfAAAA__9k3RVe">