[Bug fortran/100972] New: Missing error with "implicit none (external)"

[Bug fortran/100972] New: Missing error with "implicit none (external)"

[gscfq@t-online.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100972

            Bug ID: 100972
           Summary: Missing error with "implicit none (external)"
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gscfq@t-online.de
  Target Milestone: ---

In the following example function g has no known interface and is
not declared external. implicit none (external) does not catch it.
Affects versions down to at least r5.


$ cat z1.f90
program p
   implicit none (external)
   real, external :: f
   real :: a, b
   a = f()
   b = g()
end


$ gfortran-12-20210606 -c z1.f90
$

BTW, ifort/ifx 2021.2 gets it right with
error #8889: Explicit declaration of the EXTERNAL attribute is required. [G]

[Bug fortran/100972] Missing error with "implicit none (external)"

[gscfq@t-online.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100972

--- Comment #1 from G. Steinmetz <gscfq@t-online.de> ---

Similarly, the helpful option -Wimplicit-procedure does not warn :
(-Wimplicit-procedure : Warn if a procedure is called that has neither
an explicit interface nor has been declared as EXTERNAL.)

$ gfortran-12-20210606 -c z1.f90 -Wimplicit-procedure
$

And the following error message refers to "IMPORT" :

$ _g2_v12test -c z1.f90 -std=f2008
z1.f90:2:19:

    2 |    implicit none (external)
      |                   1
Error: Fortran 2018: IMPORT NONE with spec list at (1)

[Bug fortran/100972] Missing error with "implicit none (external)"

[aldot at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100972

Bernhard Reutner-Fischer <aldot at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1
           Keywords|                            |patch
   Last reconfirmed|                            |2021-10-31
                 CC|                            |aldot at gcc dot gnu.org
                URL|                            |https://gcc.gnu.org/piperma
                   |                            |il/gcc-patches/2021-October
                   |                            |/582979.html

--- Comment #2 from Bernhard Reutner-Fischer <aldot at gcc dot gnu.org> ---
Confirmed

[Bug fortran/100972] Missing error with "implicit none (external)"

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100972

--- Comment #3 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Bernhard Reutner-Fischer
<aldot@gcc.gnu.org>:

https://gcc.gnu.org/g:1727bb533ede295a3ef2dd494225d27b6d1746aa

commit r12-4961-g1727bb533ede295a3ef2dd494225d27b6d1746aa
Author: Bernhard Reutner-Fischer <aldot@gcc.gnu.org>
Date:   Sun Oct 31 17:44:45 2021 +0100

    Fortran: Missing error with IMPLICIT none (external) [PR100972]

    gcc/fortran/ChangeLog:

            PR fortran/100972
            * decl.c (gfc_match_implicit_none): Fix typo in warning.
            * resolve.c (resolve_unknown_f): Reject external procedures
            without explicit EXTERNAL attribute whe IMPLICIT none (external)
            is in effect.

    gcc/testsuite/ChangeLog:

            PR fortran/100972
            * gfortran.dg/implicit_14.f90: Adjust error.
            * gfortran.dg/external_implicit_none_3.f08: New test.

[Bug fortran/100972] Missing error with "implicit none (external)"

[aldot at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100972

Bernhard Reutner-Fischer <aldot at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |FIXED
      Known to work|                            |12.1.0

--- Comment #4 from Bernhard Reutner-Fischer <aldot at gcc dot gnu.org> ---
Fixed for 12.1.0 onwards.

[Bug fortran/100972] Missing error with "implicit none (external)"

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100972

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |12.0