<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/150035>150035</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [flang] I/O Runtime failure with `BLANK=zero` in READ
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          DanielCChen
      </td>
    </tr>
</table>

<pre>
    Consider the following code:
```
      implicit none

      integer, parameter :: in = 11

      real(4)    :: rl4
      real(8)    :: rl8
      complex(4) :: cx4
      complex(8) :: cx8

      open(in, file='modeBlankNaNInfIO002.dat', blank='zero')

      ! read the values in using BLANK mode of ZERO
      read(in, *, blank='zero')  rl4, rl8, cx4, cx8

      ! read the values in using BLANK mode of NULL
      read(in, *, blank='null')  rl4, rl8, cx4, cx8

      ! read the values in using BLANK mode of ZERO
      read(in, *, blank='zero')  rl4, rl8, cx4, cx8

 close(in)

      end
```

The `modeBlankNaNInfIO002.dat` is:
```
 -NaN(Q)   -NaN(S)   (  +Inf  ,+3.14  ) (Infinity   ,  NaN(_abcd123)   )
 -NaN(Q)   -NaN(S)   (  +Inf  ,+3.14  ) (Infinity   ,  NaN(_abcd123)   )
 +NaN(S)   +NaN(Q)   (  -3.14  ,  -NaN()  ) (  -Infinity , nan )
  +NaN(S) +NaN(Q)   (  -3.14  ,  -NaN()  ) (  -Infinity , nan )
```

Flang failed at execution as:
```
> a.out

fatal Fortran runtime error(t.f:19): Bad real input data at column 44 of record 3
IOT/Abort trap(coredump)
```

Both gfortran and XLF executes the code successfully.

If I remove all of the `blank=` specifier from the `open` and `read` statements, it works fine.
</pre>
<img width="1" height="1" alt="" src="http://email.email.llvm.org/o/eJy8VV2L4zYU_TXKy2WMLNuJ8-AHJxlD6JCh0y2UvhTZuk7UlSUjyfPRX1-kOOlMmIVSujsMURSde8790hV3Th41YkWKDSl2Cz75k7HVjmuJars9oV60RrxVW6OdFGjBnxB6o5R5kfoInRFIsprQmizp_E9riH9yGJXspAdtNAbE9UB7PKIlbAsjt3xAjxYCS1aD1ECyHaTpewOLXBFW5oStw3aGWpXfIspbRHlFdGYYFb5eaGZE95p_gig_IMr3rpgRNWGl1MH7Xiok2Y6w1WAEbhTXXw_8sNf9_pFSlgjuCVsFYBuOzsi_0Jr46_o9LWFpiEHE9D5zNaELqZhcSPLmoT78BEECTA-_3z89vo9bXN0hrP6mGMR0sW3MCdvGwONS_kc3Dr8-PPxbN_Sk1Hdy4ztlo1PG4Uz1oVCoxU2zE1p_OSGQJf1mEywpSPfJNbk78ANh5c_nrp13v5x3hJXhY7PXfVi3hG2yJM3D93U43OteaunfInQLcDb-g7edSFl24Vj_QBnCNjfUmw_CUeruwr69ehJPZzmAu6tiwGiuL_Q3_P8v-01BG8X1EXouFQrgHvAVu8lLo4F_UkeS3QNPzOTPxj33XEFjrLdcg520lwMCWmssYaVPepLV6TroZjVsuIjDC6QeJw-Cex4EO6OmQUOehx632BkrICO03j9-IaypW2M9eMtHwsrOWBTTMH4ayMb4Exz72ReuBfz20MzhoIv3K4xwcFPXoXP9pNRbcjbd97AHi4N5RuBKBUf8uc-vV2pJwY3YyV6ihd6a4YKIU3JJoyBZ0ngvA9hzjwNq70L2pYcXY7866KXGZCGqTKyzNV9gla6KLF0XZcoWp2q9LOhKUMFXYpW2RVuUoi1L2okiTXGZ4UJWjLKCrhhL84KmadJ3bJUjdqJkS0bbjOQUBy5VotTzkBh7XEjnJqzSgtKsWCjeonLxAWSsD5UnWT2XjTAWXkVbBdO7djo6klMlnXf_kHnpVXw_z7bFDvaENY_wNFc-tNFkEV6kP4VsxAFGsl0cR2E0aHi6r3eLyarq5P0YO4w1hDVH6U9Tm3RmIKwJevNyN1rzJ3aesCZG4ghr5mCeK_Z3AAAA__8uwCyv">