Crash: infinite recursion to cycle bounds

[DartBot]

This issue was originally filed by [email protected]

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What steps will reproduce the problem?
Dartc compile this code.

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class A<T> {}
class C<T extends T> extends A<T> {}
main() {}

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Compiled results:

java.lang.StackOverflowError
    at com.google.dart.compiler.type.TypeVariableImplementation.getKind(TypeVariableImplementation.java:72)
    at com.google.dart.compiler.type.Types.asInstanceOf(Types.java:249)
    at com.google.dart.compiler.type.Types.asInstanceOf(Types.java:287)
    at com.google.dart.compiler.type.Types.asInstanceOf(Types.java:287)
    at com.google.dart.compiler.type.Types.asInstanceOf(Types.java:287)
    at com.google.dart.compiler.type.Types.asInstanceOf(Types.java:287)
    at com.google.dart.compiler.type.Types.asInstanceOf(Types.java:287)
    at com.google.dart.compiler.type.Types.asInstanceOf(Types.java:287)
    at com.google.dart.compiler.type.Types.asInstanceOf(Types.java:287)
    at com.google.dart.compiler.type.Types.asInstanceOf(Types.java:287)
    at com.google.dart.compiler.type.Types.asInstanceOf(Types.java:287)
        ...

[DartBot]

This comment was originally written by [email protected]

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other case:

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class A<T> {}
class C<T1 extends T2, T2 extends T1> extends A<T1> {}
main() {}

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[DartBot]

This comment was originally written by [email protected]

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Added Area-Compiler, Triaged labels.

[DartBot]

This comment was originally written by [email protected]

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Set owner to [email protected].

[DartBot]

This comment was originally written by [email protected]

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Added Started label.

[DartBot]

This comment was originally written by [email protected]

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class C<T extends T> extends A<T> {} and class C<T1 extends T2, T2 extends T1> extends A<T1> {} have cyclic upper bounds on the type parameters and should probably result in a type error.

I don't recall seeing this restriction on the spec though although I may have missed it.

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cc @gbracha.

[gbracha]

Yes, this is missing and should be a static type warning.

[DartBot]

This comment was originally written by [email protected]

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Removed Priority-Medium label.
Added Priority-High label.

[DartBot]

This comment was originally written by [email protected]

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Set owner to [email protected].

[DartBot]

This comment was originally written by [email protected]

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http://codereview.chromium.org/9186017/

[DartBot]

This comment was originally written by [email protected]

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r3751

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Added Fixed label.