C51: Error 200 (Left Side of '.' Requires Struct/Union)

Information in this article applies to:

C51 Version 6 generates the following error message when I compile my old Version 5 code.

*** ERROR 200 IN LINE 10 OF .\MAIN.C: left side of '.' requires struct/union

What's wrong?

C51 V5.x accepted some structure pointer operations without generating syntax errors. For example:

The following code works fine in C51 V5.x.

   1          struct s { char v; };
   2
   3          void func (struct s *sp)  {
   4   1        sp.v = 0;
   5   1      }

However, it generates the above error in C51 V6.x.

To fix this problem, check your structure pointer accesses to be sure that the points-to operator (->) is used instead of the dot operator (.).

In the above example, the syntax sp.v needs to be replace with sp->v.

   1          struct s { char v; };
   2
   3          void func (struct s *sp)  {
   4   1        sp->v = 0;
   5   1      }