On Wed, Oct 24, 2007 at 03:06:42PM -0700, Joe Buck wrote: > On Wed, Oct 24, 2007 at 01:37:25PM -0700, Andrew Pinski wrote: > > On 10/24/07, Jack Lloyd <[EMAIL PROTECTED]> wrote: > > > Is there a reason it's not just an error, then? (As a user) I don't > > > see the point of something being a warning when the compiled code is > > > intentionally set up to crash. > > > > Because the C++ standard (and the C standard) has mentioned that you > > cannot diagnostic an undefined runtime behavior. So the code is valid > > semantically but undefined at runtime. > > But the way that the object is passed in this case, and the stack layout, > are completely defined on any platform that obeys the cross-platform API > you will find at > > http://www.codesourcery.com/cxx-abi/ > > and this definition specifies that everything will look exactly the same > as if it were a POD with the same members declared in the same order.
I don't think that's true. I believe the non-POD must be passed in memory, but GCC would be permitted to pass the POD in a register if it preferred. The layout is defined by the C++ ABI, but not the argument passing conventions. -- Daniel Jacobowitz CodeSourcery
