Fix erasure of trait info #264
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After erasure, traits always extend object, and no other class. The change flushed out three more problems, one in the handling of Super trees in erasure, another in bridge method generation. and a third that class RepeatedParam had Seq, which is a trait, as first parent.
odersky
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Dec 11, 2014
The previous scheme derived the right bounds, but then failed to use them because a TypeRef already has a set info (its bounds). Changing the bounds in the symbol by a side effect does not affect that. This is good! But it showed that the previous scheme was too fragile because it used a sneaky side effect when updating the symbol info which failed to propgate into the cached info in TypeRef. We now keep GADT computed bounds separate form the symbol info in a map `gadt` in the current context.
odersky
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Dec 16, 2014
The previous scheme derived the right bounds, but then failed to use them because a TypeRef already has a set info (its bounds). Changing the bounds in the symbol by a side effect does not affect that. This is good! But it showed that the previous scheme was too fragile because it used a sneaky side effect when updating the symbol info which failed to propgate into the cached info in TypeRef. We now keep GADT computed bounds separate form the symbol info in a map `gadt` in the current context.
odersky
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Dec 19, 2014
Fixed #264 - failure to typecheck GADTs
tgodzik
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Apr 29, 2025
Backport "Warn universal extensions on opaque types" to 3.3 LTS
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After erasure, traits always extend object, and no other class.
The change flushed out three more problems, one in the handling of
Super trees in erasure, another in bridge method generation. and a
third that class RepeatedParam had Seq, which is a trait, as first parent.
Review by @DarkDimius