PH33348: VECTOR OPTION CAUSES SOME UNIT TESTS TO FAIL, USING ZOS V2.4 XL C/C++

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• VECTOR OPTION CAUSES SOME UNIT TESTS TO FAIL, USING XL C/C++ FOR
  LINUX, V16.1
  
  ----------------------------------------------------------------
  
  
  =====COMPILE COMMAND:
  
  xlc t.c -qarch=12 -qvector -qfloat=ieee -q64 -qphaseid -qlist=./
   -O2
  
  
  
  ====TESTCASE:
  
  #include <stdlib.h>
  #include <time.h>
  
  #define ARRAY_SIZE 50
  
  void bar(double aa[ARRAY_SIZE][ARRAY_SIZE]) {
    printf("%f\n", aa[0][0]);
    return;
  }
  
  double foo(double a, double b, double c, double d, double e,
  double f, double g, double h, double i, double j, double k,
  double l, double m, double n, double o, double p, double q,
  double r, double s, double t, double u, double v, double w,
  double x, double y) {
    double z = a*b*c*d*e*f*g*h*i*j*k*l*m*n*o*p*q*r*s*t*u*v*w*x*y;
    double z2 = a+b+c+d+e+f+g+h+i+j+k+l+m+n+o+p+q+r+s+t+u+v+w+x+y;
    double aa[ARRAY_SIZE][ARRAY_SIZE];
  
    for (int ii = 0; ii < ARRAY_SIZE; ii++) {
      for (int jj = 0; jj < ARRAY_SIZE; jj++) {
        aa[ii][jj] = rand()/RAND_MAX * 10.0;
      }
    }
    bar(aa);
    return z-z2;
  }
  
  int main() {
    srand(time(NULL));
    double a = (double)rand()/RAND_MAX * 10.0;
    double b = (double)rand()/RAND_MAX * 10.0;
    double c = (double)rand()/RAND_MAX * 10.0;
    double d = (double)rand()/RAND_MAX * 10.0;
    double e = (double)rand()/RAND_MAX * 10.0;
    double f = (double)rand()/RAND_MAX * 10.0;
    double g = (double)rand()/RAND_MAX * 10.0;
    double h = (double)rand()/RAND_MAX * 10.0;
    double i = (double)rand()/RAND_MAX * 10.0;
    double j = (double)rand()/RAND_MAX * 10.0;
    double k = (double)rand()/RAND_MAX * 10.0;
    double l = (double)rand()/RAND_MAX * 10.0;
    double m = (double)rand()/RAND_MAX * 10.0;
    double n = (double)rand()/RAND_MAX * 10.0;
    double o = (double)rand()/RAND_MAX * 10.0;
    double p = (double)rand()/RAND_MAX * 10.0;
    double q = (double)rand()/RAND_MAX * 10.0;
    double r = (double)rand()/RAND_MAX * 10.0;
    double s = (double)rand()/RAND_MAX * 10.0;
    double t = (double)rand()/RAND_MAX * 10.0;
    double u = (double)rand()/RAND_MAX * 10.0;
    double v = (double)rand()/RAND_MAX * 10.0;
    double w = (double)rand()/RAND_MAX * 10.0;
    double x = (double)rand()/RAND_MAX * 10.0;
    double y = (double)rand()/RAND_MAX * 10.0;
    double z =
  foo(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y);
  
    if (z == (a*b*c*d*e*f*g*h*i*j*k*l*m*n*o*p*q*r*s*t*u*v*w*x*y -
  (a+b+c+d+e+f+g+h+i+j+k+l+m+n+o+p+q+r+s+t+u+v+w+x+y)))
      return 55;
    else
      return 66;
  }
  

Local fix

• N/A
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: Users compiling with the VECTOR, ARCH>=11,   *
  *                 FLOAT(IEEE) options and with stack frames    *
  *                 larger than 4095 bytes                       *
  ****************************************************************
  * PROBLEM DESCRIPTION: Compiled program could have undefined   *
  *                      behaviour related to passed float,      *
  *                      double or long double parameters        *
  ****************************************************************
  * RECOMMENDATION: Compile with NOVECTOR                        *
  ****************************************************************
  N/A
  

Problem conclusion

• Use workaround or apply patch
  

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:

Modules/Macros

• CCNECICS CCNECWI  CCNED240 CCNEDSCT CCNEDWRT CCNEFILT CCNEHIFC
  CCNEIPA3 CCNEIPAO CCNEMDEP CCNEOPTP CCNEP    CCNEPP   CCNETBY
  CCNMSGE  CCNMSGT  CCNQIPA
  

Fix information

• Fixed component name

  C/C++ FOR MVS

• Fixed component ID

  56551210A

Applicable component levels

• R7C0 PSY UI73821

     UP21/03/26 P F103

Fix is available

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