Testing OpenMP on new poide 8 rc2

[lingo]

Meanwhile i processed some tests with OpenMP.
Note: Never used it before, so maybe i misunderstood things.

But there are some strange results, i didn't expected:

First: It seems not possible to debug an openmp program directly
(only with disabledopenmp option).

Then, there is some odd behaviour:
Take example (using Win7 64-bit). So,
- It shall not necessary to use omp.h, but it crashes without it.
- Otherwise without using omp.h, it crashes not, if i use /Ze.
  M$ extensions shall also not necessary using the code.

Code Select Expand


#define _USE_MATH_DEFINES

#include <stdio.h>
//#include <omp.h>
#include <math.h>

int main(int argc, char *argv[])
{
    const int size = 256;
    double sinTable[size];
   
    #pragma omp parallel for
    for(int n=0; n<size; ++n)
      sinTable[n] = sin(2 * M_PI * n / size);
    return 0;
}


Whats Your experience?

Thx
Lingo

[TimoVJL]

Seems to be a bug in x64.
occasionally trash esi, when when compiled without -Ze and optimization.

EDIT: example project

[Pelle]

Can I get the *exact* compiler options please, since I can't immediately see a problem here...

[lingo]

Can I get the *exact* compiler options please, since I can't immediately see a problem here...

The program above crashes with these compiler options:

-std:C11 -Tx64-coff -Ot -Ob1 -fp:precise -W1 -Gr -openmp

Hint: Further examinations show, that the sharing of the size
variable - exactly the declaration as const - seems the problem.

HTH
Lingo