Auto merge of #19613 - emilio:slotted-list, r=jdm
Auto merge of #19613 - emilio:slotted-list, r=jdm

style: Workaround a likely valgrind false-positive.

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peterjoel/servo,anthgur/servo,cbrewster/servo,sadmansk/servo,upsuper/servo,mattnenterprise/servo,paulrouget/servo,upsuper/servo,DominoTree/servo,nnethercote/servo,avadacatavra/servo,cbrewster/servo,nnethercote/servo,nnethercote/servo,notriddle/servo,szeged/servo,sadmansk/servo,SimonSapin/servo,cbrewster/servo,fiji-flo/servo,emilio/servo,DominoTree/servo,splav/servo,DominoTree/servo,pyfisch/servo,saneyuki/servo,peterjoel/servo,SimonSapin/servo,larsbergstrom/servo,sadmansk/servo,emilio/servo,saneyuki/servo,jimberlage/servo,szeged/servo,splav/servo,DominoTree/servo,thiagopnts/servo,dati91/servo,cbrewster/servo,jimberlage/servo,peterjoel/servo,mattnenterprise/servo,larsbergstrom/servo,thiagopnts/servo,DominoTree/servo,pyfisch/servo,mbrubeck/servo,szeged/servo,jimberlage/servo,sadmansk/servo,saneyuki/servo,notriddle/servo,pyfisch/servo,notriddle/servo,ConnorGBrewster/servo,KiChjang/servo,dati91/servo,szeged/servo,splav/servo,fiji-flo/servo,upsuper/servo,cbrewster/servo,avadacatavra/servo,notriddle/servo,mbrubeck/servo,anthgur/servo,paulrouget/servo,mattnenterprise/servo,DominoTree/servo,anthgur/servo,paulrouget/servo,KiChjang/servo,splav/servo,thiagopnts/servo,szeged/servo,avadacatavra/servo,cbrewster/servo,pyfisch/servo,fiji-flo/servo,canaltinova/servo,DominoTree/servo,szeged/servo,splav/servo,sadmansk/servo,peterjoel/servo,jimberlage/servo,anthgur/servo,saneyuki/servo,nnethercote/servo,nnethercote/servo,KiChjang/servo,ConnorGBrewster/servo,sadmansk/servo,sadmansk/servo,avadacatavra/servo,nnethercote/servo,splav/servo,splav/servo,SimonSapin/servo,mbrubeck/servo,pyfisch/servo,pyfisch/servo,sadmansk/servo,peterjoel/servo,jimberlage/servo,KiChjang/servo,KiChjang/servo,nnethercote/servo,ConnorGBrewster/servo,DominoTree/servo,larsbergstrom/servo,paulrouget/servo,dati91/servo,jimberlage/servo,mbrubeck/servo,canaltinova/servo,KiChjang/servo,splav/servo,saneyuki/servo,anthgur/servo,jimberlage/servo,thiagopnts/servo,saneyuki/servo,DominoTree/servo,emilio/servo,pyfisch/servo,larsbergstrom/servo,upsuper/servo,canaltinova/servo,emilio/servo,KiChjang/servo,jimberlage/servo,peterjoel/servo,notriddle/servo,emilio/servo,notriddle/servo,larsbergstrom/servo,paulrouget/servo,dati91/servo,ConnorGBrewster/servo,mattnenterprise/servo,ConnorGBrewster/servo,larsbergstrom/servo,cbrewster/servo,SimonSapin/servo,fiji-flo/servo,canaltinova/servo,canaltinova/servo,pyfisch/servo,nnethercote/servo,emilio/servo,szeged/servo,canaltinova/servo,nnethercote/servo,thiagopnts/servo,upsuper/servo,avadacatavra/servo,nnethercote/servo,mattnenterprise/servo,thiagopnts/servo,anthgur/servo,szeged/servo,larsbergstrom/servo,thiagopnts/servo,notriddle/servo,mbrubeck/servo,avadacatavra/servo,larsbergstrom/servo,upsuper/servo,mattnenterprise/servo,canaltinova/servo,paulrouget/servo,fiji-flo/servo,cbrewster/servo,szeged/servo,peterjoel/servo,paulrouget/servo,avadacatavra/servo,peterjoel/servo,emilio/servo,pyfisch/servo,notriddle/servo,pyfisch/servo,ConnorGBrewster/servo,emilio/servo,emilio/servo,upsuper/servo,mbrubeck/servo,ConnorGBrewster/servo,SimonSapin/servo,fiji-flo/servo,canaltinova/servo,peterjoel/servo,KiChjang/servo,paulrouget/servo,ConnorGBrewster/servo,saneyuki/servo,mattnenterprise/servo,saneyuki/servo,saneyuki/servo,upsuper/servo,KiChjang/servo,DominoTree/servo,SimonSapin/servo,emilio/servo,SimonSapin/servo,KiChjang/servo,avadacatavra/servo,saneyuki/servo,thiagopnts/servo,larsbergstrom/servo,dati91/servo,szeged/servo,anthgur/servo,splav/servo,mbrubeck/servo,mattnenterprise/servo,mbrubeck/servo,dati91/servo,paulrouget/servo,fiji-flo/servo,dati91/servo,fiji-flo/servo,notriddle/servo,SimonSapin/servo,notriddle/servo,anthgur/servo,jimberlage/servo,paulrouget/servo,splav/servo,dati91/servo,peterjoel/servo,larsbergstrom/servo