Hello, > Hmm, I'm pretty sure that the type of "signed int" << "unsigned long" is > "signed int". (Yes it is, see 6.5.7.) "signed int" is 32 bits long and > the largest value is 2^31-1. 2^31 overflows and the overflow behaviour > of signed integers is undefined. Oops, that explains a lot. Sorry for the noise, then, you probably can close that bug. Thanks ! Vincent Fourmond