MAINT: Fix old gcc build and force loop unrolling
MAINT: Fix old gcc build and force loop unrolling

e-q/scipy,tylerjereddy/scipy,ilayn/scipy,scipy/scipy,zerothi/scipy,Eric89GXL/scipy,scipy/scipy,e-q/scipy,mdhaber/scipy,endolith/scipy,anntzer/scipy,Eric89GXL/scipy,scipy/scipy,Stefan-Endres/scipy,Eric89GXL/scipy,andyfaff/scipy,rgommers/scipy,vigna/scipy,ilayn/scipy,Stefan-Endres/scipy,andyfaff/scipy,matthew-brett/scipy,rgommers/scipy,mdhaber/scipy,grlee77/scipy,ilayn/scipy,scipy/scipy,rgommers/scipy,endolith/scipy,WarrenWeckesser/scipy,WarrenWeckesser/scipy,grlee77/scipy,tylerjereddy/scipy,mdhaber/scipy,endolith/scipy,anntzer/scipy,ilayn/scipy,Eric89GXL/scipy,WarrenWeckesser/scipy,WarrenWeckesser/scipy,perimosocordiae/scipy,matthew-brett/scipy,endolith/scipy,matthew-brett/scipy,Eric89GXL/scipy,rgommers/scipy,andyfaff/scipy,perimosocordiae/scipy,zerothi/scipy,zerothi/scipy,zerothi/scipy,vigna/scipy,grlee77/scipy,andyfaff/scipy,e-q/scipy,e-q/scipy,WarrenWeckesser/scipy,tylerjereddy/scipy,grlee77/scipy,vigna/scipy,mdhaber/scipy,ilayn/scipy,Stefan-Endres/scipy,Stefan-Endres/scipy,Eric89GXL/scipy,andyfaff/scipy,vigna/scipy,mdhaber/scipy,e-q/scipy,Stefan-Endres/scipy,mdhaber/scipy,tylerjereddy/scipy,scipy/scipy,vigna/scipy,andyfaff/scipy,scipy/scipy,Stefan-Endres/scipy,anntzer/scipy,perimosocordiae/scipy,perimosocordiae/scipy,zerothi/scipy,grlee77/scipy,zerothi/scipy,matthew-brett/scipy,ilayn/scipy,perimosocordiae/scipy,anntzer/scipy,WarrenWeckesser/scipy,anntzer/scipy,matthew-brett/scipy,endolith/scipy,endolith/scipy,anntzer/scipy,perimosocordiae/scipy,tylerjereddy/scipy,rgommers/scipy