https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66563
--- Comment #24 from John Paul Adrian Glaubitz <glaubitz at physik dot fu-berlin.de> --- (In reply to John Paul Adrian Glaubitz from comment #23) > It seems that Kaz was right. Downgrading libmpfr fixes the issue for me: In order to test whether this problem is actually a result of a miscompilation bug in gcc, I suggest building mpfr from source with a current gcc-4.9 and then run "make check" and see if the segfaults reproduce on native hardware.