LI73489: DUPLICATE SYMBOL WARNING WITH -G AND -O3

April 2009 Update for XL Fortran Advanced Edition for Blue Gene/L, V11.1
June 2008 Update for XL Fortran Advanced Edition for Blue Gene/L, V11.1
September 2010 Update for XL Fortran Advanced Edition for Blue Gene/L, V11.1

APAR status

• Closed as program error.

Error description

• When using both -g and -O3 together, a subroutine symbol is
  exported twice and the linker gives the following warning
  message:
  
  ld:0711-224 WARNING: Duplicate symbol: .<subroutine_symbol_name>
  
  The nm command on the binary shows the two symbols:
  
  ...
  .sub2                          T   268438256          28
  .sub3                          T   268438288          28
  .<subroutine_symbol_name>      T   268436512
  .<subroutine_symbol_name>      T   268436512        1580
  :t1=-11                        -           0
  :t1=-11                        -           0
  ...
  

Local fix

• The issue seems to go away if certain WRITE statements or
  subroutines are removed.
  

Problem summary

• USER AFFECTED:
  The problem is not always triggered.  A condition necessary to
  trigger the problem is to have multiple compilation units being
  sent to the compiler xlfcode at once.  For example, Fortran code
  and programs compiled with IPA.
  
  PROBLEM DESCRIPTION:
  A variable in the compiler xlfcode does not always get
  initialized between compilation units.  The variable could have
  the value set by a previous compilation unit.  This caused a
  symbol to be added twice to the symbol table of an object file
  and resulted in a duplicate symbol warning from the linker.
  

Problem conclusion

• We initialize the variable.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

  IZ11614

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  XL FORTRAN AE B

• Fixed component ID

  5799HJG00

Applicable component levels

• RB10 PSN IZ11614

     UP06/09/13