http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46703
--- Comment #6 from Bud Davis <bdavis at gcc dot gnu.org> --- It is a problem with Valgrind. One that is even mentioned in the (valgrind) manual. https://bugs.kde.org/show_bug.cgi?id=197915 It has been open for about 4 years, not fixed yet. Short summary. Don't use valgrind on real's larger than 64 bits. --bud davis