------- Comment #12 from rguenth at gcc dot gnu dot org 2009-12-14 13:50 ------- We don't fold anything here (because of the volatileness of z4). Thus this can't be a mpc issue but is probably libm issue.
I don't know how PPC implements _Complex float and if the HW has excess precision and thus we get extra rounding/truncating when spilling values. -funroll-loops triggers -frename-registers which again would hint at Bernds change. Assuming that the testcase from comment #6 is what this is all about (i?86-linux is fine w/ and w/o -frename-registers and w/ and w/o volatile). -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42220
