[test] Be more verbose about errors in test Interpreter/SDK/libc.swift.
[test] Be more verbose about errors in test Interpreter/SDK/libc.swift.

We're trying to track down an intermittent failure.

rdar://26960623

OscarSwanros/swift,CodaFi/swift,aschwaighofer/swift,deyton/swift,shajrawi/swift,tkremenek/swift,calebd/swift,return/swift,tinysun212/swift-windows,hooman/swift,return/swift,swiftix/swift,nathawes/swift,devincoughlin/swift,OscarSwanros/swift,gregomni/swift,tjw/swift,calebd/swift,gribozavr/swift,danielmartin/swift,gribozavr/swift,jckarter/swift,airspeedswift/swift,CodaFi/swift,jmgc/swift,tkremenek/swift,parkera/swift,JGiola/swift,karwa/swift,frootloops/swift,roambotics/swift,zisko/swift,roambotics/swift,zisko/swift,devincoughlin/swift,zisko/swift,devincoughlin/swift,airspeedswift/swift,felix91gr/swift,tjw/swift,frootloops/swift,Jnosh/swift,manavgabhawala/swift,CodaFi/swift,practicalswift/swift,nathawes/swift,shahmishal/swift,atrick/swift,parkera/swift,codestergit/swift,uasys/swift,austinzheng/swift,jckarter/swift,airspeedswift/swift,djwbrown/swift,jmgc/swift,swiftix/swift,gregomni/swift,felix91gr/swift,aschwaighofer/swift,natecook1000/swift,benlangmuir/swift,rudkx/swift,Jnosh/swift,felix91gr/swift,aschwaighofer/swift,practicalswift/swift,shahmishal/swift,sschiau/swift,deyton/swift,rudkx/swift,practicalswift/swift,bitjammer/swift,shahmishal/swift,sschiau/swift,shahmishal/swift,gribozavr/swift,apple/swift,nathawes/swift,felix91gr/swift,nathawes/swift,arvedviehweger/swift,codestergit/swift,atrick/swift,return/swift,codestergit/swift,xwu/swift,jckarter/swift,Jnosh/swift,xedin/swift,karwa/swift,lorentey/swift,milseman/swift,parkera/swift,jckarter/swift,hughbe/swift,tkremenek/swift,Jnosh/swift,brentdax/swift,CodaFi/swift,huonw/swift,brentdax/swift,milseman/swift,allevato/swift,xedin/swift,karwa/swift,amraboelela/swift,lorentey/swift,jopamer/swift,manavgabhawala/swift,glessard/swift,xwu/swift,arvedviehweger/swift,allevato/swift,ahoppen/swift,hooman/swift,alblue/swift,airspeedswift/swift,austinzheng/swift,jopamer/swift,tkremenek/swift,shajrawi/swift,gribozavr/swift,sschiau/swift,austinzheng/swift,zisko/swift,jmgc/swift,hughbe/swift,lorentey/swift,tjw/swift,danielmartin/swift,calebd/swift,hooman/swift,gribozavr/swift,jmgc/swift,frootloops/swift,harlanhaskins/swift,OscarSwanros/swift,felix91gr/swift,OscarSwanros/swift,CodaFi/swift,arvedviehweger/swift,xwu/swift,swiftix/swift,glessard/swift,austinzheng/swift,shahmishal/swift,gregomni/swift,apple/swift,brentdax/swift,nathawes/swift,calebd/swift,tjw/swift,JGiola/swift,benlangmuir/swift,bitjammer/swift,shajrawi/swift,atrick/swift,tjw/swift,apple/swift,danielmartin/swift,amraboelela/swift,airspeedswift/swift,rudkx/swift,return/swift,atrick/swift,rudkx/swift,natecook1000/swift,alblue/swift,deyton/swift,parkera/swift,calebd/swift,tinysun212/swift-windows,karwa/swift,arvedviehweger/swift,stephentyrone/swift,swiftix/swift,amraboelela/swift,jopamer/swift,austinzheng/swift,djwbrown/swift,harlanhaskins/swift,huonw/swift,karwa/swift,parkera/swift,amraboelela/swift,sschiau/swift,jmgc/swift,uasys/swift,shahmishal/swift,tjw/swift,deyton/swift,hughbe/swift,uasys/swift,glessard/swift,brentdax/swift,alblue/swift,OscarSwanros/swift,jtbandes/swift,stephentyrone/swift,Jnosh/swift,sschiau/swift,manavgabhawala/swift,stephentyrone/swift,CodaFi/swift,tinysun212/swift-windows,xedin/swift,hooman/swift,xedin/swift,jtbandes/swift,jtbandes/swift,hughbe/swift,apple/swift,jopamer/swift,alblue/swift,JGiola/swift,manavgabhawala/swift,uasys/swift,frootloops/swift,harlanhaskins/swift,karwa/swift,OscarSwanros/swift,karwa/swift,glessard/swift,benlangmuir/swift,apple/swift,airspeedswift/swift,lorentey/swift,milseman/swift,huonw/swift,sschiau/swift,airspeedswift/swift,brentdax/swift,felix91gr/swift,manavgabhawala/swift,xwu/swift,deyton/swift,aschwaighofer/swift,natecook1000/swift,benlangmuir/swift,allevato/swift,tkremenek/swift,brentdax/swift,tinysun212/swift-windows,devincoughlin/swift,allevato/swift,nathawes/swift,xedin/swift,manavgabhawala/swift,tkremenek/swift,djwbrown/swift,codestergit/swift,harlanhaskins/swift,alblue/swift,xedin/swift,JGiola/swift,shajrawi/swift,stephentyrone/swift,rudkx/swift,parkera/swift,sschiau/swift,hughbe/swift,manavgabhawala/swift,atrick/swift,bitjammer/swift,parkera/swift,natecook1000/swift,return/swift,shajrawi/swift,arvedviehweger/swift,codestergit/swift,deyton/swift,jtbandes/swift,frootloops/swift,jckarter/swift,gregomni/swift,lorentey/swift,xwu/swift,brentdax/swift,shajrawi/swift,jopamer/swift,gregomni/swift,uasys/swift,rudkx/swift,djwbrown/swift,stephentyrone/swift,amraboelela/swift,tinysun212/swift-windows,devincoughlin/swift,bitjammer/swift,allevato/swift,practicalswift/swift,jtbandes/swift,bitjammer/swift,practicalswift/swift,sschiau/swift,jmgc/swift,alblue/swift,xwu/swift,tinysun212/swift-windows,xwu/swift,austinzheng/swift,alblue/swift,harlanhaskins/swift,djwbrown/swift,deyton/swift,danielmartin/swift,karwa/swift,amraboelela/swift,tkremenek/swift,atrick/swift,uasys/swift,benlangmuir/swift,allevato/swift,ahoppen/swift,parkera/swift,allevato/swift,return/swift,Jnosh/swift,uasys/swift,frootloops/swift,arvedviehweger/swift,gregomni/swift,glessard/swift,jtbandes/swift,devincoughlin/swift,shahmishal/swift,milseman/swift,zisko/swift,natecook1000/swift,calebd/swift,roambotics/swift,harlanhaskins/swift,hughbe/swift,glessard/swift,jckarter/swift,frootloops/swift,nathawes/swift,aschwaighofer/swift,practicalswift/swift,shajrawi/swift,huonw/swift,milseman/swift,xedin/swift,stephentyrone/swift,hughbe/swift,calebd/swift,swiftix/swift,tinysun212/swift-windows,huonw/swift,roambotics/swift,amraboelela/swift,apple/swift,natecook1000/swift,ahoppen/swift,Jnosh/swift,natecook1000/swift,CodaFi/swift,danielmartin/swift,OscarSwanros/swift,bitjammer/swift,roambotics/swift,zisko/swift,lorentey/swift,stephentyrone/swift,swiftix/swift,milseman/swift,ahoppen/swift,lorentey/swift,aschwaighofer/swift,JGiola/swift,huonw/swift,gribozavr/swift,practicalswift/swift,milseman/swift,danielmartin/swift,hooman/swift,hooman/swift,return/swift,ahoppen/swift,swiftix/swift,xedin/swift,tjw/swift,ahoppen/swift,zisko/swift,gribozavr/swift,djwbrown/swift,devincoughlin/swift,benlangmuir/swift,roambotics/swift,shajrawi/swift,codestergit/swift,shahmishal/swift,harlanhaskins/swift,huonw/swift,lorentey/swift,felix91gr/swift,practicalswift/swift,aschwaighofer/swift,codestergit/swift,danielmartin/swift,djwbrown/swift,bitjammer/swift,arvedviehweger/swift,jckarter/swift,JGiola/swift,hooman/swift,devincoughlin/swift,austinzheng/swift,jtbandes/swift,gribozavr/swift,jmgc/swift,jopamer/swift,jopamer/swift