Micro Focus Visual COBOL 2.3 Update 2 for Eclipse (UNIX) > Programming > COBOL Programming > Creating 64-bit Native COBOL Programs > Scan64 > Examples of Using Scan64 > Constant and Variable Reference Modification

Constant and Variable Reference Modification

Create the intermediate code file:
```
cobol -a demo5.cbl
```
In this program the record p1 is accessed via a reference modification, both statically and dynamically.

Run Scan64 on this program by entering the command:

cobscan64 -m demo5

This produces the following report:

Processing file 'demo5.int' 
**Unsafe modification of pointer at (file: demo5.cbl, line: 12) 
  Modifier : P1 (file: demo5.cbl, def: 6)
  Pointer : PTR2-1 (file: demo5.cbl, def: 8) 

**Unsafe modification of pointer at (file: demo5.cbl, line: 13) 
  Modifier : P1 (file: demo5.cbl, def: 6) 
  Pointer : PTR2-1 (file: demo5.cbl, def: 8)

**Unsafe modification of pointer at (file: demo5.cbl, line: 13)
  Modifier : P1 (file: demo5.cbl, def: 6) 
  Pointer : PTR2-2 (file: demo5.cbl, def: 9) 

**Unsafe modification of pointer at (file: demo5.cbl, line: 14) 
  Modifier : P1 (file: demo5.cbl, def: 6)
  Pointer : PTR2-1 (file: demo5.cbl, def: 8) 

**Unsafe modification of pointer at (file: demo5.cbl, line: 14)
  Modifier : P1 (file: demo5.cbl, def: 6)
  Pointer : PTR2-2 (file: demo5.cbl, def: 9)

Finished file 'demo5.int' - pointer problems could exist

The first static reference modification at line 11 is correctly not reported; however the second static reference modification at line 12 will overwrite the first byte of ptr2-1, so is reported as a violation.

At line 13 and line 14, at syntax-check the Compiler has no idea what the contents of the variable refm might be, so any pointer within the record p1 could be changed; Scan64 therefore reports possible violations of the two pointers ptr2-1 and ptr2-2.