8342090: Infer::IncorporationBinaryOp::equals can produce side-effects

[vicente-romero-oracle]

Type inference uses a cache to store incorporation operations already done. This way we can avoid redoing operations that once done won't produce any change. This can reduce the compilation time when the number of inference variables involved is not trivial. The elements in the cache are implemented with class com.sun.tools.javac.comp.Infer::IncorporationBinaryOp the problem here is that the equals method of this class can produce side effects, implying that after a comparison the compared objects can mutate. This patch is fixing this issue,

TIA

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Progress

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Warning

 ⚠️ Found leading lowercase letter in issue title for 8288590: javac failure: incompatible types: cannot infer type arguments due to Object.hashCode collision

Issues

• JDK-8342090: Infer::IncorporationBinaryOp::equals can produce side-effects (Bug - P4)
• JDK-8288590: javac failure: incompatible types: cannot infer type arguments due to Object.hashCode collision (Bug - P3)

Contributors

• Maurizio Cimadamore <[email protected]>

Reviewing

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