diff options
Diffstat (limited to 'src/dotty/tools/dotc/core/ConstraintHandling.scala')
| -rw-r--r-- | src/dotty/tools/dotc/core/ConstraintHandling.scala | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/src/dotty/tools/dotc/core/ConstraintHandling.scala b/src/dotty/tools/dotc/core/ConstraintHandling.scala index 3835d553c..95fa40704 100644 --- a/src/dotty/tools/dotc/core/ConstraintHandling.scala +++ b/src/dotty/tools/dotc/core/ConstraintHandling.scala @@ -162,7 +162,8 @@ trait ConstraintHandling { /** Solve constraint set for given type parameter `param`. * If `fromBelow` is true the parameter is approximated by its lower bound, * otherwise it is approximated by its upper bound. However, any occurrences - * of the parameter in a refinement somewhere in the bound are removed. + * of the parameter in a refinement somewhere in the bound are removed. Also + * wildcard types in bounds are approximated by their upper or lower bounds. * (Such occurrences can arise for F-bounded types). * The constraint is left unchanged. * @return the instantiating type @@ -174,6 +175,9 @@ trait ConstraintHandling { def apply(tp: Type) = mapOver { tp match { case tp: RefinedType if param occursIn tp.refinedInfo => tp.parent + case tp: WildcardType => + val bounds = tp.optBounds.orElse(TypeBounds.empty).bounds + if (fromBelow == (variance >= 0)) bounds.lo else bounds.hi case _ => tp } } |