Comment # 2 on bug 1110092 from Michal Srb

I tried to compile the code with clang-6 and gcc-7. In both cases valgrind
gives me multiple errors, including one like the one you posted. In both cases
there is also following warning on top:

  Warning: client switching stacks?  SP change: 0x1ffefff750 --> 0x1ffebff680
  to suppress, use: --max-stackframe=4194512 or greater

When I add the suggested parameter to valgrind, all errors are gone in both
clang-6 and gcc-7.

Do you observe the same thing? If not, have you tried if gcc makes a
difference? Please also attach the full valgrind output.