Torquil Macdonald Sørensen <torquil@xxxxxxxxx> writes: > It seems a bit strange to me that it would be a Blitz++ problem, since > everything has worked fine using the same version of blitz++ (0.9) for > a long time, with compiler versions all the way from after 4.1.3 up to > and including 4.5.3. But not 4.6.1... Right now I don't remember if > the strict-alising issue I had with 4.1.3 broke compilation or > generated incorrect numerical results, though. Every new version of the compiler improves optimizations. And code with invalid aliasing is often be compiled to behave as the programmer expects, entirely by accident. So there is nothing particularly surprising in having invalid code which only acts surprisingly with certain compiler versions. It could certainly also be a bug in gcc. My experience is that aliasing issues are due to invalid code, but compiler bugs are possible too. I would have to see a complete example to be sure. Ian
