The function uses _mm_load_pd even though EIGEN_ALIGN16 is not properly defined.
Created attachment 117 [details]
Sample code to reproduce the bug.
"The function" is of course
template<typename MatrixType, typename ResultType>
struct compute_inverse_size4<Architecture::SSE, double, MatrixType, ResultType>
I can reproduce in 32bit mode only, with SSE2:
g++ main.cpp -o main -O2 -I eigen -lrt -m32 -msse2
Created attachment 120 [details]
Created attachment 121 [details]
Created attachment 122 [details]
Fixed by b2a24739db97.
New test added: dontalign.cp, does various stuff on various types with both EIGEN_DONT_ALIGN and EIGEN_DONT_ALIGN_STATICALLY.