Make erased export forwarders inline methods

Author: odersky

compiler/src/dotty/tools/dotc/core/Flags.scala

@@ -540,7 +540,7 @@ object Flags {
   val RetainedModuleClassFlags: FlagSet = RetainedModuleValAndClassFlags | Enum
 
   /** Flags retained in term export forwarders */
-  val RetainedExportTermFlags = Infix | Given | Implicit | Inline | Transparent | Erased | HasDefaultParams | NoDefaultParams | ExtensionMethod
+  val RetainedExportTermFlags = Infix | Given | Implicit | Inline | Transparent | HasDefaultParams | NoDefaultParams | ExtensionMethod
 
   /** Flags retained in parameters of term export forwarders */
   val RetainedExportTermParamFlags = Given | Implicit | Erased | HasDefault | Inline

compiler/src/dotty/tools/dotc/typer/Namer.scala

@@ -1326,6 +1326,7 @@ class Namer { typer: Typer =>
                     else mbr.info.ensureMethodic
                   (EmptyFlags, mbrInfo)
               var mbrFlags = MandatoryExportTermFlags | maybeStable | (sym.flags & RetainedExportTermFlags)
+              if sym.is(Erased) then mbrFlags |= Inline
               if pathMethod.exists then mbrFlags |= ExtensionMethod
               val forwarderName = checkNoConflict(alias, span)
               newSymbol(cls, forwarderName, mbrFlags, mbrInfo, coord = span)

tests/pos/erased-export.scala

@@ -0,0 +1,9 @@
+import language.experimental.erasedDefinitions
+
+class C(x: Int):
+  erased val e = x
+
+class D:
+  val c = C(22)
+  export c.*
+  erased val x = e