gperftools doesn't work

gperftools (aka Google Profiler) produces no useful output.

E.g., this code:

#include "gperftools/profiler.h"
#include <iostream>
#include <math.h>
using namespace std;
void bar()
{
  int a,b,c,d,j,k;
  a=0;
  int z=0;
  b = 1000;
  while(z < b)
    {
      while (a < b)
        {
          d = sin(a);
          c = cos(a);
          j = tan(a);
          k = tan(a);
          k = d * c + j *k;
          a++;
        }
      a = 0;
      z++;
    }
}

int main()
{
  ProfilerStart("prof.out");

  bar();
  ProfilerFlush();
  ProfilerStop();
}

produces the following output on a real Ubuntu machine:

$ CPUPROFILE=prof.out ./test
PROFILE: interrupts/evictions/bytes = 26/2/1848

but this output on WSL:

$ CPUPROFILE=prof.out ./test
PROFILE: interrupts/evictions/bytes = 0/0/64

Trying to dump prof.out indeed shows it is empty:

$ google-pprof ./test --svg prof.out
Using local file ./test.
Using local file prof.out.
No nodes to print

I tried running with various levels of PERFTOOLS_VERBOSE, but was not able to obtain any leads on where the problem might be.

Start by compiling and running the provided gperftools example on Ubuntu and WSL, comparing the CPUPROFILE output and the generated prof.out file. Then investigate why WSL reports zero interrupts and why google-pprof reports no nodes. Done means identifying the WSL-specific cause and documenting or fixing profiling so the example produces useful output.