Be more careful setting the Stable flag

odersky · odersky · commit 483a595e25c4 · 2018-12-06T13:25:14.000+01:00
diff --git a/compiler/src/dotty/tools/dotc/core/CheckRealizable.scala b/compiler/src/dotty/tools/dotc/core/CheckRealizable.scala
@@ -82,7 +82,7 @@ class CheckRealizable(implicit ctx: Context) {
             // roughly: it's realizable if the info does not have bad bounds
             realizability(tp.info).mapError(r => new ProblemInUnderlying(tp, r))
         r andAlso {
-          sym.setFlag(Stable)
+          if (sym.isStable) sym.setFlag(Stable) // it's known to be stable and realizable
           realizability(tp.prefix)
         }
       }

Original file line number	Diff line number	Diff line change
`@@ -82,7 +82,7 @@ class CheckRealizable(implicit ctx: Context) {`
`82`	`82`	`// roughly: it's realizable if the info does not have bad bounds`
`83`	`83`	`realizability(tp.info).mapError(r => new ProblemInUnderlying(tp, r))`
`84`	`84`	`r andAlso {`
`85`		`- sym.setFlag(Stable)`
	`85`	`+ if (sym.isStable) sym.setFlag(Stable) // it's known to be stable and realizable`
`86`	`86`	`realizability(tp.prefix)`
`87`	`87`	`}`
`88`	`88`	`}`