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Stack overflow with incorrect mapped type as constraint of type parameter #17847

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@sandersn

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@sandersn
function sum<T extends { [P in T]: number }, K extends keyof T>() {
    n += v[k];
}

This incorrect code puts the compiler in an infinite loop:

     RangeError: Maximum call stack size exceeded
      at Object.contains (src/compiler/core.ts:276:5)
      at getBaseConstraint (src/compiler/checker.ts:5955:21)
      at getResolvedBaseConstraint (src/compiler/checker.ts:5949:36)
      at hasNonCircularBaseConstraint (src/compiler/checker.ts:5936:20)
      at getConstraintOfTypeParameter (src/compiler/checker.ts:5906:20)
      at getConstraintTypeFromMappedType (src/compiler/checker.ts:5761:56)
      at isGenericMappedType (src/compiler/checker.ts:5798:84)
      at computeBaseConstraint (src/compiler/checker.ts:5997:21)
      at getBaseConstraint (src/compiler/checker.ts:5960:32)
      at computeBaseConstraint (src/compiler/checker.ts:5969:38)
      at getBaseConstraint (src/compiler/checker.ts:5960:32)

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