[Bug tree-optimization/54000] [4.6/4.7/4.8 Regression] Performance breakdown for gcc-4.{6,7} vs. gcc-4.5 using std::vector in matrix vector multiplication

[benedict.geihe at ins dot uni-bonn.de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54000

--- Comment #6 from Benedict Geihe <benedict.geihe at ins dot uni-bonn.de> 2012-09-05 09:30:05 UTC ---
I originally reported that using a C array instead of STL's vector solves the
problem. I am afraid that was wrong. I can also not remember what lead me to
this conclusion.

Anyway I attached a new minimal example without STL stuff. Hope it helps.