http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60843
--- Comment #1 from joseph at codesourcery dot com <joseph at codesourcery dot com> --- On Tue, 15 Apr 2014, kdevel at vogtner dot de wrote: > For conversion to a type of width N, the value is reduced modulo 2^N to be > within range of the type; no signal is raised." > > Reduce A modulo M usually means find the least integer R in the range [0, M - > 1] such that A is congruent R modulo M. But this is not what gcc compiled I don't see the problem. It explicitly says "reduced modulo 2^N to be within range of the type", and that unambiguously defines the result value, as there is exactly one result within the range of the type that is equal to the input, modulo 2^N. The qualifier "to be within range of the type" says that [0, M - 1] is irrelevant, because that isn't the range of the type in question. This is the normal form of modulo arithmetic for signed types, as used for example by -fwrapv (and defined in detail in the first (1994) edition of LIA-1; the second (2012) edition removes the modulo operations, but the underlying wrap_I operation is in LIA-2).
