ninja: Entering directory `out/gn'
[0/1] Regenerating ninja files
ERROR at //llvm/unittests/Target/X86/BUILD.gn:24:1: Invalid token.
	"X86SelectionDAGTest.cpp",
^
You got a tab character in here. Tabs are evil. Convert to spaces.
FAILED: build.ninja.stamp 
../../llvm/utils/gn/bin/linux-amd64/gn --root=../.. -q --dotfile=../../llvm/utils/gn/.gn --regeneration gen .
ninja: error: rebuilding 'build.ninja': subcommand failed
Command '['ninja', '-C', 'out/gn']' returned non-zero exit status 1.