BUG: Fix ticket #1588/gh issue #398, refcount error in clip
BUG: Fix ticket #1588/gh issue #398, refcount error in clip

This patch enforces a strict dichotomy for the variables 'indescr'
and 'newdescr', so they are either NULL, or they own a reference.
Following the consequences of this allowed the reference error
to be tracked down.

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