LI80750: INTERNAL COMPILER ERROR WHEN COMPILING WITH -QSMP=OMP

APAR status

• Closed as program error.

Error description

• An internal compiler error occurs with the following test case
  with device offloading disabled:
  
  ====COMPILE COMMAND:
  xlc_r -qsmp=noopt  test.c  -c
  
  ====TESTCASE:
  $ cat test.c
  # define WIDTH      1000
  # define HEIGHT     1000
  #define SZ ((HEIGHT+2) * (WIDTH+2))
  #define IDX(i,j) (((i)*(WIDTH+2))+(j))
  
  double *Temperature_previous;
  
  void initialize(){
    int i, j;
  
  #pragma omp target map(from:Temperature_previous[0:SZ])
    {
        #pragma omp teams distribute
        for(i = 0; i <= HEIGHT+1; i++)
          for (j = 0; j <= WIDTH+1; j++)
            Temperature_previous[IDX(i,j)] = 0.0;
  
        #pragma omp teams distribute
        for(i = 0; i <= HEIGHT+1; i++)
          Temperature_previous[IDX(i,0)] = 0.0;
    }
  }
  $
  
  =====ACTUAL OUTPUT:
  Compiler produces an internal compiler error
  
  =====EXPECTED OUTPUT:
  Should compile fine
  

Local fix

• N/A
  

Problem summary

• USERS AFFECTED:
  Users compiling with -qsmp=omp may be affected by this issue.
  
  PROBLEM DESCRIPTION:
  The submitted test case exposes a user error when compared to
  the OpenMP 4.5 specification.
  This is a non-conforming program because of the following
  restriction on the teams regions:
  
  
  "If specified, a teams  construct must be contained within a
  target  construct. That target
  19 construct must contain no statements, declarations or
  directives outside of the teams  construct."
  
  
  The target region in the initialize function contains more than
  one teams region in it.
  

Problem conclusion

• The compiler has been modified to catch the above user error and
   emit a diagnostic message.
  

Temporary fix

Comments

APAR Information

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

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

  IJ16752

Fix information

• Fixed component name

  XL C/C++ LINUX

• Fixed component ID

  5725C7310

Applicable component levels