src/source_io.f90(159): error #5082: Syntax error, found ',' when expecting one of: =
function integer  calculate(a,b, oper  ) result(res)
-------------------------------^
src/source_io.f90(159): error #5132: Syntax error, found IDENTIFIER 'RESULT' when expecting one of: <END-OF-STATEMENT> ; BIND
function integer  calculate(a,b, oper  ) result(res)
-----------------------------------------^
src/source_io.f90(48): error #6451: A dummy argument name is required in this context.   [STR]
        character(*), intent(inout) :: str
---------------------------------------^
src/source_io.f90(63): error #6463: This is not a derived type name.   [STACK_OP]
         type(stack_op),  pointer,   intent(inout):: stack_o
--------------^
src/source_io.f90(64): error #6463: This is not a derived type name.   [STACK_NUM]
         type(stack_num), pointer, intent(inout):: numbers
--------------^
src/source_io.f90(115): error #6418: This name has already been assigned a data type.   [ELEM]
      type(operators), pointer  :: elem
-----------------------------------^
src/source_io.f90(115): error #6227: This symbol has multiple POINTER statement/attribute declarations which is not allowed.   [ELEM]
      type(operators), pointer  :: elem
-----------------------------------^
src/source_io.f90(159): error #7548: Keyword RESULT expected.   [CALCULATE]
function integer  calculate(a,b, oper  ) result(res)
------------------^
src/source_io.f90(160): error #6451: A dummy argument name is required in this context.   [A]
        integer, intent(in) :: a,b
-------------------------------^
src/source_io.f90(160): error #6451: A dummy argument name is required in this context.   [B]
        integer, intent(in) :: a,b
---------------------------------^
src/source_io.f90(161): error #6451: A dummy argument name is required in this context.   [OPER]
        character(*), intent(in) :: oper
------------------------------------^
src/source_io.f90(35): error #6366: The shapes of the array expressions do not conform.   [OP]
      op =['+','-','*','/', '(',')']
------^
src/source_io.f90(37): error #6361: An array-valued argument is required in this context.   [SIZE]
       do concurrent (i = 1:Size(op))
---------------------------------^
src/source_io.f90(38): error #6410: This name has not been declared as an array or a function.   [OP]
           if(op(i) == ch) then
--------------^
src/source_io.f90(38): error #6303: The assignment operation or the binary expression operation is invalid for the data types of the two operands.   [OP]
           if(op(i) == ch) then
--------------^
src/source_io.f90(40): error #8431: A RETURN statement shall not appear within a DO CONCURRENT construct.
               return
---------------^
src/source_io.f90(32): error #8238: A colon may be used as a type parameter value only in the declaration of an entity or component that has the POINTER or ALLOCATABLE attribute.   [OP]
      character(:) :: op
----------------------^
src/source_io.f90(53): error #6404: This name does not have a type, and must have an explicit type.   [IO]
             read(in, "(a)", iostat=IO) str
------------------------------------^
src/source_io.f90(53): error #7838: A scalar default-integer variable is required in this context.   [IO]
             read(in, "(a)", iostat=IO) str
------------------------------------^
src/source_io.f90(46): error #6288: A CHARACTER function name must not be declared with an asterisk type-param-value (i.e., (LEN=*)) if the function is a module function.   [READ_STR]
  function Read_str(InputFile) result (str)
-----------^
src/source_io.f90(69): error #6404: This name does not have a type, and must have an explicit type.   [STACK_O]
                   call addOperator(str(1:1),stack_o,numbers)
---------------------------------------------^
src/source_io.f90(69): error #6478: A type-name must not be used as a variable.   [NUMBERS]
                   call addOperator(str(1:1),stack_o,numbers)
-----------------------------------------------------^
src/source_io.f90(69): error #6633: The type of the actual argument differs from the type of the dummy argument.   [NUMBERS]
                   call addOperator(str(1:1),stack_o,numbers)
-----------------------------------------------------^
src/source_io.f90(69): error #7496: A non-pointer actual argument shall have a TARGET attribute when associated with a pointer dummy argument.   [STACK_O]
                   call addOperator(str(1:1),stack_o,numbers)
---------------------------------------------^
src/source_io.f90(69): error #7496: A non-pointer actual argument shall have a TARGET attribute when associated with a pointer dummy argument.   [NUMBERS]
                   call addOperator(str(1:1),stack_o,numbers)
-----------------------------------------------------^
src/source_io.f90(71): error #6404: This name does not have a type, and must have an explicit type.   [I]
                   do i=1, size(str)
----------------------^
src/source_io.f90(71): error #6063: An INTEGER or REAL data type is required in this context.   [I]
                   do i=1, size(str)
----------------------^
src/source_io.f90(71): error #6361: An array-valued argument is required in this context.   [SIZE]
                   do i=1, size(str)
--------------------------------^
src/source_io.f90(75): error #6410: This name has not been declared as an array or a function.   [TMP]
                        tmp(i) = str(i:i)
------------------------^
src/source_io.f90(75): error #6303: The assignment operation or the binary expression operation is invalid for the data types of the two operands.   [STR]
                        tmp(i) = str(i:i)
---------------------------------^
src/source_io.f90(239): catastrophic error: Too many errors, exiting
compilation aborted for src/source_io.f90 (code 1)