LI74354: COMPILE-TIME PERFORMANCE ISSUE

March 2009 Update for XL C/C++ for Linux, V10.1
October 2009 Update for XL C/C++ for Linux, V10.1
June 2011 Update for XL C/C++ for Linux, V10.1
XL C/C++ for Linux Fix Pack 8 (January 2014 Update) for 10.1
August 2010 Update for XL C/C++ for Linux, V10.1
January 2011 Update for XL C/C++ for Linux, V10.1
January 2012 Update for XL C/C++ for Linux, V10.1
July 2012 Update for XL C/C++ for Linux, V10.1

APAR status

• Closed as program error.

Error description

• In some situations, when optimization is used, compile-time
  becomes much longer.
  

Local fix

• Using -qalias=noansi may help to improve the compile-time
  performance.
  

Problem summary

• Users may experience long compile-time when compiling a
  testcase at -O and higher optimization level.
  
  The old algorithm for walking the aliasing graph in some
  template testcases becomes exponentially larger when the number
  of nested template testcase is instantiated is increased by 1.
  

Problem conclusion

• We will allow the compiler to search for the applicable
  behaviour pattern and find the fix of the algorithm to avoid the
  exponentially walking of the aliasing graph.
  

Temporary fix

Comments

APAR Information

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

  IZ15784

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

  LI74426

Fix information

• Fixed component name

  XL C/C++ SLES10

• Fixed component ID

  5724U8300

Applicable component levels

• RA10 PSN IZ15784

     UP06/09/13