add bool/logical example

Author: scivision

src/c/CMakeLists.txt

@@ -6,6 +6,10 @@ add_library(error_c OBJECT error_lib.c)
 
 
 # -- C calling Fortran
+add_executable(c_fortran_bool bool_main.c)
+target_link_libraries(c_fortran_bool PRIVATE bool_fortran)
+add_test(NAME C_Fortran_bool COMMAND c_fortran_bool)
+
 add_executable(c_fortran_submodule submodule_main.c)
 target_link_libraries(c_fortran_submodule PRIVATE submodule_fortran)
 set_target_properties(c_fortran_submodule PROPERTIES LINKER_LANGUAGE C)

src/c/bool_main.c

@@ -0,0 +1,15 @@
+#include <stdbool.h>
+#include <stdio.h>
+
+extern bool logical_not(bool);
+
+int main(void){
+
+if (!logical_not(false)) {
+  fprintf(stderr, "expected Fortran to not boolean");
+  return 1;
+}
+
+printf("OK: boolean-logical not\n");
+return 0;
+}

src/cxx/CMakeLists.txt

@@ -6,6 +6,10 @@ target_include_directories(struct_cxx PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/../c)
 add_library(error_cxx OBJECT error_lib.cxx)
 
 # -- C++ calling Fortran
+add_executable(cxx_fortran_bool bool_main.cxx)
+target_link_libraries(cxx_fortran_bool PRIVATE bool_fortran)
+add_test(NAME C++_Fortran_bool COMMAND cxx_fortran_bool)
+
 add_executable(cxx_fortran_submodule submodule_main.cxx)
 target_link_libraries(cxx_fortran_submodule PRIVATE submodule_fortran)
 target_compile_definitions(cxx_fortran_submodule PRIVATE _USE_MATH_DEFINES)

src/cxx/bool_main.cxx

@@ -0,0 +1,14 @@
+#include <iostream>
+
+extern "C" bool logical_not(bool);
+
+int main(){
+
+if (!logical_not(false)) {
+  std::cerr << "expected Fortran to not boolean" << std::endl;
+  return EXIT_FAILURE;
+}
+
+std::cout << "OK: boolean-logical not" << std::endl;
+return EXIT_SUCCESS;
+}

src/fortran/CMakeLists.txt

@@ -1,3 +1,5 @@
+add_library(bool_fortran bool_lib.f90)
+
 add_library(vector_fortran OBJECT vector_lib.f90)
 
 add_library(error_fortran OBJECT error_lib.f90)

src/fortran/bool_lib.f90

@@ -0,0 +1,20 @@
+module logbool
+
+use, intrinsic :: iso_c_binding, only : c_bool
+
+implicit none (type, external)
+
+contains
+
+logical(c_bool) function logical_not(L) bind(C)
+
+logical(c_bool), intent(in), value :: L
+logical :: byte_default
+
+logical_not = .not. L
+
+print '(a,i0,1x,i0)', "C, Fortran logical bits: ", storage_size(L), storage_size(byte_default)
+
+end function logical_not
+
+end module logbool