[Bug middle-end/59990] [4.7/4.8/4.9 regression] incorrect memcpy optimization

[joseph at codesourcery dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59990

--- Comment #1 from joseph at codesourcery dot com <joseph at codesourcery dot com> ---
Seems rather like bug 58416 to me, if I understand it correctly (SFmode 
and DFmode x87 floating-point loads wrongly used when the result is used 
other than for arithmetic).  Should only affect platforms where loads and 
stores extend signaling NaNs to a wider format and so convert them to 
quiet NaNs with an exception raised.