http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53366
--- Comment #5 from Uros Bizjak <ubizjak at gmail dot com> 2012-05-16 17:25:50 UTC --- This testcase fails with -O3 with plain SSE vectorization: --cut here-- struct S { float v[3]; }; struct T { struct S r, i; }; struct U { struct T j[2]; }; void __attribute__((noinline)) foo (struct U *__restrict p1, const float _Complex * __restrict x) { int i, j; for (j = 0; j < 2; ++j) { float a = __builtin_crealf (x[j]); float b = __builtin_cimagf (x[j]); float c = __builtin_crealf (x[j+2]); float d = __builtin_cimagf (x[j+2]); for (i = 0; i < 3; ++i) { p1->j[j].r.v[i] += a; p1->j[j].r.v[i] += c; p1->j[j].i.v[i] += b; p1->j[j].i.v[i] += d; } } } _Complex float x[4]; struct U p1; int main () { int i, j; for (i = 0; i < 4; ++i) x[i] = i + 1.0iF * (2 * i); foo (&p1, x); for (j = 0; j < 2; ++j) for (i = 0; i < 3; ++i) if (p1.j[j].r.v[i] != __builtin_crealf (x[j] + x[j+2]) || p1.j[j].i.v[i] != __builtin_cimagf (x[j] + x[j+2])) __builtin_abort (); return 0; } --cut here--