NullFrag 688 third_party/re2/re2/compile.cc return NullFrag(); // not used by caller NullFrag 694 third_party/re2/re2/compile.cc return NullFrag(); NullFrag 1010 third_party/re2/re2/compile.cc Frag f = c.WalkExponential(sre, NullFrag(), 2*c.max_inst_); NullFrag 1101 third_party/re2/re2/compile.cc Frag all = c.WalkExponential(re, NullFrag(), 2*c.max_inst_);