https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64074
--- Comment #1 from joseph at codesourcery dot com <joseph at codesourcery dot com> --- Yes, you need -mabi=spe for this to work. Any form of e500 operation without -mabi=spe (except maybe e500v1 single-precision-only non-vector floating point) will not follow any well-defined ABI. r187581 (2012-05-16, so 4.8 and later) made -mcpu= for e500 processors enable -mabi=spe by default.
