RESULT_DIAGNOSTICS_LEVEL 0

When the diagnostics level is set to 0 using the following define:
#define RESULT_DIAGNOSTICS_LEVEL 0
In a release build (with all optimizations etc), I do expect that Return_Hr is not called in the generated code. However, this is not the case when using the RETURN_IF_FAILED macro:

if ( hr < 0 )
  {
    wil::details::in1diag0::Return_Hr(retaddr, hr);
    return hr;
  }

A possible solution might be do define different helper macros, depending on RESULT_DIAGNOSTICS_LEVEL. E.g.

#if RESULT_DIAGNOSTICS_LEVEL == 0
#undef RETURN_HR_FAIL
#define RETURN_HR_FAIL RETURN_HR_FAIL_EXPECTED
#undef RETURN_IF_WIN32_BOOL_FALSE
#define RETURN_IF_WIN32_BOOL_FALSE RETURN_IF_WIN32_BOOL_FALSE_EXPECTED
#undef RETURN_LAST_ERROR_IF_NULL
#define RETURN_LAST_ERROR_IF_NULL RETURN_LAST_ERROR_IF_NULL_EXPECTED
#undef RETURN_LAST_ERROR_IF
#define RETURN_LAST_ERROR_IF RETURN_LAST_ERROR_IF_EXPECTED
#undef RETURN_IF_WIN32_ERROR
#define RETURN_IF_WIN32_ERROR RETURN_IF_WIN32_ERROR_EXPECTED
#undef RETURN_HR_IF
#define RETURN_HR_IF RETURN_HR_IF_EXPECTED
#endif 

Start by locating the definitions of RESULT_DIAGNOSTICS_LEVEL, RETURN_IF_FAILED, and the related RETURN_* macros. Inspect the optimized release output at level 0 and compare it with the expected macros listed in the issue. Done means RETURN_IF_FAILED and the affected helper macros do not emit a Return_Hr call in that configuration.