I did a bit of netsearching and I think I see the problem, although I don't have a good solution. It is a result of optimization in the call sequence in test_append that calls str.append(value,len) which calls reserve(length() + count). length() is inlined to a reference to n so the argument is treated as "n+count". This yields, in the reserve method at the bad line
if (n+count <= n) which leads to the warning/error you see. I don't see how to disable the error, though. Tuesday, July 10, 2012, 2:48:07 PM, you wrote: > On 10/07/2012, at 11:16 AM, James Peach <jpe...@apache.org> wrote: >> Hi all, >> So it seems that I have still broken the Fedora buildbot, >> http://ci.apache.org/builders/tserver-fedora-trunk/builds/1168: >> CXX test_Vec.o >> cc1plus: warnings being treated as errors >> Vec.h: In function ‘int main(int, char**)’: >> Vec.h:616: error: assuming signed overflow does not occur when assuming that >> (X + c) < X is always false >> Vec.h:616: error: assuming signed overflow does not occur when assuming that >> (X + c) < X is always false >> The error is apparantly here, which is a bit confusing: >> 614 template <class C, class A, int S> inline void >> 615 Vec<C,A,S>::reserve(int x) { >> 616 if (x <= n) >> 617 return; >> I tested that master builds fine on Fedora17 w/ gcc 4.7.0-5 and "make check" >> passes. Does anyone know what version of Fedora this buildbot is running? > And everything's cool with Fedora 13 using gcc 4.4.5-2. Any clues gratefully > accepted ... > J
