Issues with interfacing Fortran Logicals with Cython Bint

I'm currently working on wrapping a Fortran module to be called from Python using Cython, the Fortran subroutine currently has an optional logical argument. I've used iso_c_binding to wrap the subroutine, and I have written the cython .pyx file to create the .so file. However, when I run my setup script, I get two warnings:

warning: passing argument 4 of 'c_geo_manipulate' from incompatible pointer type [-Wincompatible-pointer-types]
     c_geo_manipulate(((geo *)(&__pyx_v_v1)), ((geo *)(&__pyx_v_v2)), ((geo *)(&__pyx_v_value)), ((int *)(&__pyx_v_optional_weights_output)));

And

pyginterpolation.h:17:13: note: expected '_Bool *' but argument is of type 'int *'
 extern void c_geo_manipulate(geo *v1, geo *v2, geo *v3, bool *output_weight);

Here are the files I'm using:

interpolation.f90 
module interpolation_module 
use iso_c_binding
implicit none 


type, bind(c) :: geo
    real, dimension(2) :: coordinates 
    real :: weight 
end type geo

contains 


    subroutine geo_manipulate(v1, v2, v3, output_weight)
        type(geo), intent(in) :: v1, v2
        logical, optional, intent(in) :: output_weight
        type(geo), intent(out) :: v3

        if (present(output_weight).and.(output_weight .eqv. .true.)) then 
            v3%coordinates = v1%coordinates * v1%weight + v2%coordinates * v2%weight 
            v3%weight = v1%weight + v2%weight 
        
        else
            print *, 'false'
            v3%coordinates = v1%coordinates * v1%weight + v2%coordinates * v2%weight
            v3%weight = 0
        end if 
        
    end subroutine geo_manipulate

end module interpolation_module

pyginterpolation.f90

module interpolation_interface 
use interpolation_module 
use iso_c_binding 
implicit none 


contains 


    subroutine c_geo_manipulate(v1, v2, v3, output_weight) bind(c)
        type(geo), intent(in) :: v1, v2
        type(geo), intent(out) :: v3
        logical(c_bool), optional, intent(in) :: output_weight

        if ((present(output_weight)).and.(output_weight .eqv. .true.)) then
            call geo_manipulate(v1, v2, v3, output_weight = .true.)
        else
            call geo_manipulate(v1, v2, v3)

        end if 
    end subroutine c_geo_manipulate

end module interpolation_interface

pyginterpolation.h

#include <stdbool.h>

struct _geo {
    float coordinates[2];
    float weight;
};

typedef struct _geo geo;



extern void c_geo_manipulate(geo *v1, geo *v2, geo *v3, bool *output_weight);

pyginterpolation.pyx

import numpy as np

cdef bint boolean_variable = True 

cdef extern from "pyginterpolation.h":
    ctypedef struct geo:
        float coordinates[2]
        float weight

    cdef void c_geo_manipulate(geo *v1, geo *v2, geo *v3, bint *output_weight)


def f(geo v1, geo v2, output_weights = False):
    cdef geo value
    if output_weights is True: 
        optional_weights_output = True 
        c_geo_manipulate(<geo*> &v1,<geo*> &v2,<geo*> &value, <bint*> &optional_weights_output)
        return np.array(value)
    else: 
        optional_weights_output = False
        c_geo_manipulate(<geo*> &v1,<geo*> &v2,<geo*> &value, <bint*> &optional_weights_output)
        return np.array(value.coordinates)

setup.py

from distutils.core import setup
from distutils.extension import Extension
from Cython.Distutils import build_ext
# This line only needed if building with NumPy in Cython file.
from numpy import get_include
from os import system

# compile the fortran modules without linking
fortran_mod_comp = 'gfortran interpolation.f90 -c -o interpolation.o -O3 -fPIC'
print (fortran_mod_comp)
system(fortran_mod_comp)
shared_obj_comp = 'gfortran pyginterpolation.f90 -c -o pyginterpolation.o -O3 -fPIC'
print (shared_obj_comp)
system(shared_obj_comp)

ext_modules = [Extension(# module name:
                         'pyginterpolation',
                         # source file:
                         ['pyginterpolation.pyx'],
                         # other compile args for gcc
                         extra_compile_args=['-fPIC', '-O3'],
                         # other files to link to
                         extra_link_args=['interpolation.o', 'pyginterpolation.o'])]

setup(name = 'pyginterpolation',
      cmdclass = {'build_ext': build_ext},
      # Needed if building with NumPy.
      # This includes the NumPy headers when compiling.
      include_dirs = [get_include()],
      ext_modules = ext_modules)

From what I've understood, cython has bint to be used for booleans with C, but I'm not too comfortable with how they work,and I'm still very new to C/Fortran, so my understanding of how pointers (and the language in general) work is still pretty rudimentary. Does anyone have an idea what might be wrong with my usage of these logicals?

Thanks!