[Bug fortran/105594] New: -Wuse-without-only issued for any submodule

[Bug fortran/105594] New: -Wuse-without-only issued for any submodule

[everythingfunctional at protonmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105594

            Bug ID: 105594
           Summary: -Wuse-without-only issued for any submodule
           Product: gcc
           Version: 11.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: everythingfunctional at protonmail dot com
  Target Milestone: ---

The -Wuse-without-only option issues a warning when compiling any submodule.
This is incorrect as a submodule statement is not a use statement, and cannot
contain an only qualifier.

For example the source code

module foo_m
    interface
        module subroutine foo
        end subroutine
    end interface
end module

submodule (foo_m) foo_s
contains
    module procedure foo
    end procedure
end submodule

when compiled like

$ gfortran -c -Wuse-without-only foo_m.f90
foo_m.f90:8:17:

    8 | submodule (foo_m) foo_s
      |                 1
Warning: USE statement at (1) has no ONLY qualifier [-Wuse-without-only]

[Bug fortran/105594] -Wuse-without-only issued for any submodule

[kargl at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105594

kargl at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2022-05-13
                 CC|                            |kargl at gcc dot gnu.org
           Priority|P3                          |P4

--- Comment #1 from kargl at gcc dot gnu.org ---
This patch suppresses the warning and allows the code to compile.

diff --git a/gcc/fortran/module.cc b/gcc/fortran/module.cc
index 85aa153bd77..98c056ac7e5 100644
--- a/gcc/fortran/module.cc
+++ b/gcc/fortran/module.cc
@@ -7261,7 +7261,7 @@ gfc_use_module (gfc_use_list *module)
   only_flag = module->only_flag;
   current_intmod = INTMOD_NONE;

-  if (!only_flag)
+  if (!only_flag && gfc_state_stack->state != COMP_SUBMODULE)
     gfc_warning_now (OPT_Wuse_without_only,
                     "USE statement at %C has no ONLY qualifier");

[Bug fortran/105594] -Wuse-without-only issued for any submodule

[kargl at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105594

--- Comment #2 from kargl at gcc dot gnu.org ---
Created attachment 55194
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=55194&action=edit
patch that fixes bug

Patch from comment #1 still fixes this bug.