Re: [PATCH] fortran: Fix host association in module procedure interface bodies [PR79330]

Hi Gonzalo,

the patch looks basically fine, but:

1) please sign it off, like the previous time;

2) please attach it to your mail, don't inline it.

Thanks,
Harald

On 3/28/26 12:35, Gonzalosilvalde wrote:
> Named constants from the host scope were not accessible in module
> procedure interface bodies, causing bind(C, name=...) expressions
> referencing such constants to fail.  The compiler treated the constant
> as an implicitly typed REAL(4) variable instead of resolving it from
> the enclosing module scope.
> 
> The fix sets has_import_set on the current namespace when a module
> procedure is detected inside an interface block, before bind(C) is
> parsed, so that symbol lookup can reach the host scope.
> 
> gcc/fortran/ChangeLog:
> 
> 	PR fortran/79330
> 	* decl.cc (gfc_match_subroutine): Set has_import_set when
> 	matching a module procedure inside an interface block.
> 	(gfc_match_function_decl): Likewise.
> 
> gcc/testsuite/ChangeLog:
> 
> 	PR fortran/79330
> 	* gfortran.dg/bind_c_module_proc.f90: New test.
> ---
>   gcc/fortran/decl.cc                            | 12 ++++++++++--
>   .../gfortran.dg/bind_c_module_proc.f90         | 18 ++++++++++++++++++
>   2 files changed, 28 insertions(+), 2 deletions(-)
>   create mode 100644 gcc/testsuite/gfortran.dg/bind_c_module_proc.f90
> 
> diff --git a/gcc/fortran/decl.cc b/gcc/fortran/decl.cc
> index 454b65f2c47..faf404d994a 100644
> --- a/gcc/fortran/decl.cc
> +++ b/gcc/fortran/decl.cc
> @@ -8191,7 +8191,11 @@ gfc_match_function_decl (void)
>       sym = sym->result;
>   
>     if (current_attr.module_procedure)
> -    sym->attr.module_procedure = 1;
> +    {
> +      sym->attr.module_procedure = 1;
> +      if (gfc_current_state () == COMP_INTERFACE)
> +        gfc_current_ns->has_import_set = 1;
> +    }
>   
>     gfc_new_block = sym;
>   
> @@ -8687,7 +8691,11 @@ gfc_match_subroutine (void)
>   					     &gfc_current_locus);
>   
>     if (current_attr.module_procedure)
> -    sym->attr.module_procedure = 1;
> +    {
> +      sym->attr.module_procedure = 1;
> +      if (gfc_current_state () == COMP_INTERFACE)
> +        gfc_current_ns->has_import_set = 1;
> +    }
>   
>     if (add_hidden_procptr_result (sym))
>       sym = sym->result;
> diff --git a/gcc/testsuite/gfortran.dg/bind_c_module_proc.f90 b/gcc/testsuite/gfortran.dg/bind_c_module_proc.f90
> new file mode 100644
> index 00000000000..2df933f3c14
> --- /dev/null
> +++ b/gcc/testsuite/gfortran.dg/bind_c_module_proc.f90
> @@ -0,0 +1,18 @@
> +! { dg-do compile }
> +! PR fortran/79330
> +! Verify that named constants from the host scope are accessible
> +! in module procedure interface bodies for bind(C, name=...).
> +
> +module m
> +  implicit none
> +  character(len=*), parameter :: PREFIX = "_gfortran_"
> +  interface
> +    module subroutine sub() bind(C, name=PREFIX//"caf_sub")
> +      implicit none
> +    end subroutine
> +    module function func() result(r) bind(C, name=PREFIX//"caf_func")
> +      implicit none
> +      integer :: r
> +    end function
> +  end interface
> +end module