APAR status
Closed as program error.
Error description
The exe generated from the resulting test case produces incorrect output when compiled with -qsmp=omp: ===== COMPILE COMMAND: xlC -qsmp=omp test.cpp $ cat test.cpp #include <iostream> using namespace std; int main(int argc, char **argv) { int size = 4; int dim = 3; float in[12], out[12]; float * __restrict__ x = out; float * __restrict__ y = out + 4; float * __restrict__ z = out + 8; for(int i=0; i<size*dim; i++) in[i] = out[i] = 0.0f; in[3] = in[4] = in[5] = 1.6f; #pragma omp simd for(int i=0; i<size; i++) { x[i] = in[i*dim]; y[i] = in[i*dim+1]; z[i] = in[i*dim+2]; } cout << "check out " << out[1] << " " << out [5] << " " << out [9] << std::endl; return 0; } $ ===== ACTUAL OUTPUT: $ ./a.out check out 0 0 1.6 $ ===== EXPECTED OUTPUT: $ ./a.out check out 1.6 1.6 1.6 $
Local fix
N/A
Problem summary
USERS AFFECTED: Clients using -qsmp=omp maybe affected by this issue PROBLEM DESCRIPTION: An internal optimization causing certain variables to be privatized was causing an incorrect output at runtime
Problem conclusion
This optimization has now been fixed to handle this scenario
Temporary fix
Comments
APAR Information
APAR number
LI80905
Reported component name
XL C/C++ FOR LI
Reported component ID
5725C7300
Reported release
G11
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2019-06-11
Closed date
2019-08-20
Last modified date
2019-08-20
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
Fix information
Fixed component name
XL C/C++ LINUX
Fixed component ID
5725C7310
Applicable component levels
[{"Business Unit":{"code":"BU058","label":"IBM Infrastructure w\/TPS"},"Product":{"code":"SSXVZZ","label":"XL C\/C++ for Linux"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"G11","Edition":"","Line of Business":{"code":"LOB57","label":"Power"}}]
Document Information
Modified date:
20 August 2019