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• With Passing an Address as an Argument to a Function

1. Products and Versions Concerned
   (1) The C compiler package for the M32C series*1 (M3T-NC308WA)
         V.5.00 Release 1 through V.5.40 Release 00
   (2) The C compiler package for the M16C series*2 (M3T-NC30WA)
         V.5.00 Release 1 through V.5.40 Release 00A

   *1. Generic name of the M32C/90, M32C/80, and M16C/80 series
   *2. Generic name of the M16C/60, /30, /20, /10, /Tiny, and R8C/Tiny 
       series

2. Description
   When the address of a variable is used as an argument to a function,
   an incorrect value may be passed to the function.

3. Conditions
   This problem occurs if the following conditions are all satisfied:
   (1) A call to a function is made, where the address of 
       an automatic variable is used as an argument to the 
       function.
   (2) Immediately after the function called in (1) is performed, execution 
       returns from the function that made the call to the function in (1).
   (3) Optimizing options -OS and -O5 are both selected.

   Example:
   -------------------------------------
   void sub(int *);
   void func(void)
   {
         int i;
         sub(&i);   /* Conditions (1) and (2) */
   } 
   void sub(int *i) 
   {
   . . . . . . . . . . . . . . . . . . . . . .
   }
   -------------------------------------

4. Workaround
   Place a dummy asm function immediately after the line describing the 
   call to a function that takes the address of an automatic
   variable as an argument
   -------------------------------------
   void func(void)
   {
            int i;

            sub(&i);
            asm("");
   }
   -------------------------------------

5. Schedule of Fixing the Problem
   This problem has already been fixed in the following versions:
   (1) The C compiler package for the M32C series V.5.41 Release 00 
       and later
   (2) The C compiler package for the M16C series V.5.42 Release 00 
       and later
   So use the latest version of each package.