BLD: try linking a file if compile long double repr detection fails
BLD: try linking a file if compile long double repr detection fails

When compiler uses link time optimization it will not emit the binary
representation of the long double during linking. This prevents building
numpy with -flto.
To avoid this try linking the object when the compile detection failed.
With this change numpy can be built with link time optimization with 4 worker
processes using following command:

CC='gcc -fno-fat-lto-objects -flto=4 -fuse-linker-plugin -O3' \
LDSHARED='gcc -fno-fat-lto-objects -flto=4 -fuse-linker-plugin -shared
-O3' AR=gcc-ar \
python setup.py build_ext

See also:
https://www.mail-archive.com/numpy-discussion@scipy.org/msg45535.html

Should also work with icc's -ipo switch (probably closes gh-4992)

skymanaditya1/numpy,seberg/numpy,mindw/numpy,dwillmer/numpy,mortada/numpy,Eric89GXL/numpy,dimasad/numpy,MichaelAquilina/numpy,gfyoung/numpy,chatcannon/numpy,GrimDerp/numpy,GaZ3ll3/numpy,ContinuumIO/numpy,mattip/numpy,kirillzhuravlev/numpy,rajathkumarmp/numpy,pyparallel/numpy,rhythmsosad/numpy,kiwifb/numpy,jakirkham/numpy,leifdenby/numpy,yiakwy/numpy,dimasad/numpy,tacaswell/numpy,rherault-insa/numpy,brandon-rhodes/numpy,KaelChen/numpy,stuarteberg/numpy,nbeaver/numpy,WarrenWeckesser/numpy,chatcannon/numpy,chiffa/numpy,bmorris3/numpy,Linkid/numpy,cowlicks/numpy,WarrenWeckesser/numpy,pbrod/numpy,nguyentu1602/numpy,yiakwy/numpy,simongibbons/numpy,Srisai85/numpy,empeeu/numpy,naritta/numpy,dato-code/numpy,ChanderG/numpy,has2k1/numpy,skymanaditya1/numpy,moreati/numpy,ChanderG/numpy,mathdd/numpy,groutr/numpy,njase/numpy,utke1/numpy,ahaldane/numpy,ContinuumIO/numpy,tdsmith/numpy,KaelChen/numpy,jorisvandenbossche/numpy,rhythmsosad/numpy,cowlicks/numpy,ssanderson/numpy,MSeifert04/numpy,tynn/numpy,trankmichael/numpy,WillieMaddox/numpy,abalkin/numpy,sinhrks/numpy,naritta/numpy,rherault-insa/numpy,dwillmer/numpy,pyparallel/numpy,mingwpy/numpy,chiffa/numpy,simongibbons/numpy,utke1/numpy,hainm/numpy,groutr/numpy,skymanaditya1/numpy,sonnyhu/numpy,ContinuumIO/numpy,CMartelLML/numpy,BMJHayward/numpy,ddasilva/numpy,mhvk/numpy,AustereCuriosity/numpy,madphysicist/numpy,MichaelAquilina/numpy,trankmichael/numpy,pdebuyl/numpy,WillieMaddox/numpy,sigma-random/numpy,rudimeier/numpy,jakirkham/numpy,dch312/numpy,ahaldane/numpy,jonathanunderwood/numpy,mwiebe/numpy,bringingheavendown/numpy,leifdenby/numpy,pbrod/numpy,mattip/numpy,nbeaver/numpy,mindw/numpy,mattip/numpy,chatcannon/numpy,jorisvandenbossche/numpy,Anwesh43/numpy,Linkid/numpy,ajdawson/numpy,BMJHayward/numpy,empeeu/numpy,behzadnouri/numpy,ekalosak/numpy,shoyer/numpy,grlee77/numpy,gmcastil/numpy,b-carter/numpy,WarrenWeckesser/numpy,skwbc/numpy,joferkington/numpy,kiwifb/numpy,pizzathief/numpy,seberg/numpy,solarjoe/numpy,utke1/numpy,charris/numpy,nguyentu1602/numpy,sonnyhu/numpy,simongibbons/numpy,SunghanKim/numpy,SiccarPoint/numpy,CMartelLML/numpy,mathdd/numpy,mwiebe/numpy,githubmlai/numpy,sinhrks/numpy,drasmuss/numpy,ahaldane/numpy,ViralLeadership/numpy,b-carter/numpy,rhythmsosad/numpy,Dapid/numpy,musically-ut/numpy,WillieMaddox/numpy,solarjoe/numpy,simongibbons/numpy,rgommers/numpy,bmorris3/numpy,Anwesh43/numpy,ddasilva/numpy,anntzer/numpy,mhvk/numpy,musically-ut/numpy,rudimeier/numpy,argriffing/numpy,groutr/numpy,mattip/numpy,GaZ3ll3/numpy,MSeifert04/numpy,cowlicks/numpy,pbrod/numpy,bertrand-l/numpy,numpy/numpy,SiccarPoint/numpy,abalkin/numpy,jschueller/numpy,dato-code/numpy,cjermain/numpy,tacaswell/numpy,rmcgibbo/numpy,ekalosak/numpy,mwiebe/numpy,numpy/numpy,BabeNovelty/numpy,jankoslavic/numpy,larsmans/numpy,BMJHayward/numpy,moreati/numpy,tacaswell/numpy,Eric89GXL/numpy,MichaelAquilina/numpy,SunghanKim/numpy,hainm/numpy,WarrenWeckesser/numpy,numpy/numpy,tynn/numpy,jankoslavic/numpy,grlee77/numpy,ChristopherHogan/numpy,jonathanunderwood/numpy,dato-code/numpy,ajdawson/numpy,felipebetancur/numpy,yiakwy/numpy,seberg/numpy,shoyer/numpy,jschueller/numpy,jorisvandenbossche/numpy,GrimDerp/numpy,kirillzhuravlev/numpy,githubmlai/numpy,ahaldane/numpy,ddasilva/numpy,ChanderG/numpy,pizzathief/numpy,argriffing/numpy,jschueller/numpy,rmcgibbo/numpy,MaPePeR/numpy,brandon-rhodes/numpy,Srisai85/numpy,anntzer/numpy,CMartelLML/numpy,Srisai85/numpy,rajathkumarmp/numpy,anntzer/numpy,joferkington/numpy,GaZ3ll3/numpy,shoyer/numpy,gmcastil/numpy,Anwesh43/numpy,ekalosak/numpy,WarrenWeckesser/numpy,pdebuyl/numpy,bringingheavendown/numpy,ViralLeadership/numpy,ChristopherHogan/numpy,tdsmith/numpy,jorisvandenbossche/numpy,jankoslavic/numpy,mingwpy/numpy,Yusa95/numpy,mhvk/numpy,bringingheavendown/numpy,pbrod/numpy,BMJHayward/numpy,leifdenby/numpy,nguyentu1602/numpy,ssanderson/numpy,simongibbons/numpy,tdsmith/numpy,ESSS/numpy,Eric89GXL/numpy,ESSS/numpy,larsmans/numpy,cjermain/numpy,has2k1/numpy,sonnyhu/numpy,githubmlai/numpy,pizzathief/numpy,ajdawson/numpy,drasmuss/numpy,jakirkham/numpy,rherault-insa/numpy,MaPePeR/numpy,ChristopherHogan/numpy,brandon-rhodes/numpy,pdebuyl/numpy,sonnyhu/numpy,joferkington/numpy,stuarteberg/numpy,maniteja123/numpy,mortada/numpy,charris/numpy,rmcgibbo/numpy,sinhrks/numpy,grlee77/numpy,bertrand-l/numpy,maniteja123/numpy,MSeifert04/numpy,Yusa95/numpy,Yusa95/numpy,shoyer/numpy,cjermain/numpy,MichaelAquilina/numpy,mhvk/numpy,Dapid/numpy,shoyer/numpy,GaZ3ll3/numpy,pbrod/numpy,endolith/numpy,hainm/numpy,Anwesh43/numpy,dato-code/numpy,sigma-random/numpy,dimasad/numpy,charris/numpy,bertrand-l/numpy,mortada/numpy,behzadnouri/numpy,rgommers/numpy,Dapid/numpy,sinhrks/numpy,b-carter/numpy,trankmichael/numpy,jonathanunderwood/numpy,njase/numpy,rudimeier/numpy,empeeu/numpy,tdsmith/numpy,madphysicist/numpy,sigma-random/numpy,endolith/numpy,BabeNovelty/numpy,rajathkumarmp/numpy,behzadnouri/numpy,skwbc/numpy,cjermain/numpy,Srisai85/numpy,chiffa/numpy,ajdawson/numpy,SiccarPoint/numpy,grlee77/numpy,SiccarPoint/numpy,dch312/numpy,dwillmer/numpy,SunghanKim/numpy,maniteja123/numpy,mindw/numpy,AustereCuriosity/numpy,dch312/numpy,MSeifert04/numpy,Linkid/numpy,endolith/numpy,brandon-rhodes/numpy,AustereCuriosity/numpy,ESSS/numpy,mindw/numpy,larsmans/numpy,CMartelLML/numpy,skwbc/numpy,githubmlai/numpy,ekalosak/numpy,sigma-random/numpy,anntzer/numpy,Eric89GXL/numpy,rgommers/numpy,abalkin/numpy,madphysicist/numpy,Yusa95/numpy,MaPePeR/numpy,dch312/numpy,hainm/numpy,rgommers/numpy,mathdd/numpy,dwillmer/numpy,jorisvandenbossche/numpy,ChristopherHogan/numpy,kirillzhuravlev/numpy,nguyentu1602/numpy,musically-ut/numpy,pdebuyl/numpy,gmcastil/numpy,njase/numpy,rhythmsosad/numpy,argriffing/numpy,has2k1/numpy,madphysicist/numpy,has2k1/numpy,felipebetancur/numpy,pizzathief/numpy,rudimeier/numpy,mathdd/numpy,tynn/numpy,gfyoung/numpy,joferkington/numpy,ssanderson/numpy,kiwifb/numpy,BabeNovelty/numpy,BabeNovelty/numpy,charris/numpy,Linkid/numpy,gfyoung/numpy,moreati/numpy,seberg/numpy,madphysicist/numpy,MaPePeR/numpy,dimasad/numpy,kirillzhuravlev/numpy,felipebetancur/numpy,naritta/numpy,endolith/numpy,bmorris3/numpy,musically-ut/numpy,MSeifert04/numpy,ahaldane/numpy,mhvk/numpy,KaelChen/numpy,ViralLeadership/numpy,felipebetancur/numpy,stuarteberg/numpy,mingwpy/numpy,jakirkham/numpy,GrimDerp/numpy,cowlicks/numpy,pyparallel/numpy,stuarteberg/numpy,KaelChen/numpy,pizzathief/numpy,mingwpy/numpy,grlee77/numpy,ChanderG/numpy,numpy/numpy,GrimDerp/numpy,larsmans/numpy,naritta/numpy,bmorris3/numpy,mortada/numpy,jakirkham/numpy,jankoslavic/numpy,trankmichael/numpy,empeeu/numpy,yiakwy/numpy,drasmuss/numpy,SunghanKim/numpy,rajathkumarmp/numpy,rmcgibbo/numpy,skymanaditya1/numpy,jschueller/numpy,nbeaver/numpy,solarjoe/numpy