error: use Fortran 2018 std

Author: scivision

CMakeLists.txt

@@ -2,7 +2,7 @@ cmake_minimum_required(VERSION 3.14...3.21)
 
 project(Fortran_C_CXX_interface
 LANGUAGES C CXX Fortran
-VERSION 1.2.0)
+VERSION 1.2.1)
 
 include(CTest)
 

README.md

@@ -49,7 +49,6 @@ export CFLAGS=$CXXFLAGS
 Using Fortran statement "stop" or "error stop" with a C/C++ main program works like with a Fortran main program.
 The "error*" examples show this.
 
-
 ## References
 
 * [StackOverflow](

src/fortran/error.f90

@@ -5,7 +5,7 @@ module utils
 
 contains
 
-subroutine error_fortran(value) bind(C)
+pure subroutine error_fortran(value) bind(C)
 
   integer(c_int), intent(in) :: value