In file included from class_multiple_trace_bases.cpp:5:
./class_multiple_trace_bases.h:22:1: warning: [blink-gc] Class 'Derived' requires a trace method.
class Derived : public Base, public Mixin {
^
./class_multiple_trace_bases.h:22:17: note: [blink-gc] Untraced base class 'Base' declared here:
class Derived : public Base, public Mixin {
                ^
./class_multiple_trace_bases.h:22:30: note: [blink-gc] Untraced base class 'Mixin' declared here:
class Derived : public Base, public Mixin {
                             ^
./class_multiple_trace_bases.h:22:1: warning: [blink-gc] Class 'Derived' which inherits from GarbageCollectedMixin must locally declare and override trace(Visitor*)
class Derived : public Base, public Mixin {
^
2 warnings generated.