SQL 'implicitly' qualifying fields

I have this V5R3 SQLRPGLE program.  Somehow the precompiler implicitly 
qualifies the datastructure, (at times).
I have a pmr open, but just want to make sure that I am not doing 
something wrong.
>From the compile listing:
...
     DSYSSTSHSTF     E DS                  EXTNAME(SYSSTSHST)
...
     D                 DS      FETCH
     D  SQL_00006              1      2B 0 INZ(064)      length of header
     D  SQL_00007              3      4B 0 INZ(5)      statement number
     D  SQL_00008              5      8B 0 INZ(0)      invocation mark
     D  SQL_00009              9      9A   INZ('0')      data is okay
     D  SQL_00010             10     63A      end of header
     D  SQL_00011             65     72A      SYSTEMNAME
     D  SQL_00012      S                   LIKE(SYSSTSHSTF.SYSTEMNAME  )
...
     C*EXEC SQL
     C* FETCH S1 INTO :SYSTEMNAME
     C*END-EXEC
     C                   Z-ADD     -4            SQLER6      SQL   5
     C                   CALL      SQLROUTE      SQL
     C                   PARM                    SQLCA      SQL
     C                   PARM                    SQL_00006      SQL
     C     SQL_00009     IFEQ      '1'      SQL
     C                   EVAL      SYSTEMNAME = SQL_00011      SQL
...
     C*EXEC SQL
     C* CONNECT TO :Systemname
     C*END-EXEC
     C                   EVAL      SQL_00012    = SYSSTSHSTF.SYSTEMNAME   
SQL
...

WRKPTFGRP
PTF Group             Level  Status 
SF99530                4153  Installed
SF99529                   4  Installed
SF99503                   1  Installed
SF99275                   1  Installed

Rob Berendt
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