Merge pull request #13594 from dotty-staging/fix-13532

Ignore StaleSymbol exceptions when testing whether dependencies shoul…

Author: odersky

compiler/src/dotty/tools/dotc/sbt/ExtractDependencies.scala

@@ -14,6 +14,7 @@ import dotty.tools.dotc.core.Names._
 import dotty.tools.dotc.core.Phases._
 import dotty.tools.dotc.core.StdNames._
 import dotty.tools.dotc.core.Symbols._
+import dotty.tools.dotc.core.Denotations.StaleSymbol
 import dotty.tools.dotc.core.Types._
 import dotty.tools.dotc.transform.SymUtils._
 import dotty.tools.dotc.util.{SrcPos, NoSourcePosition}
@@ -340,12 +341,17 @@ private class ExtractDependenciesCollector extends tpd.TreeTraverser { thisTreeT
     else DependencyByInheritance
 
   private def ignoreDependency(sym: Symbol)(using Context) =
-    !sym.exists ||
-    sym.isAbsent(canForce = false) || // ignore dependencies that have a symbol but do not exist.
-                                      // e.g. java.lang.Object companion object
-    sym.isEffectiveRoot ||
-    sym.isAnonymousFunction ||
-    sym.isAnonymousClass
+    try
+      !sym.exists ||
+      sym.isAbsent(canForce = false) || // ignore dependencies that have a symbol but do not exist.
+                                        // e.g. java.lang.Object companion object
+      sym.isEffectiveRoot ||
+      sym.isAnonymousFunction ||
+      sym.isAnonymousClass
+    catch case ex: StaleSymbol =>
+      // can happen for constructor proxies. Test case is pos-macros/i13532.
+      true
+
 
   /** Traverse the tree of a source file and record the dependencies and used names which
    *  can be retrieved using `dependencies` and`usedNames`.

compiler/src/dotty/tools/dotc/semanticdb/ExtractSemanticDB.scala

@@ -13,6 +13,7 @@ import Flags._
 import Names.Name
 import StdNames.nme
 import NameOps._
+import Denotations.StaleSymbol
 import util.Spans.Span
 import util.{SourceFile, SourcePosition}
 import transform.SymUtils._
@@ -241,8 +242,13 @@ class ExtractSemanticDB extends Phase:
               if imported != nme.WILDCARD then
                 for alt <- tree.expr.tpe.member(imported).alternatives do
                   registerUseGuarded(None, alt.symbol, sel.imported.span, tree.source)
-                  if (alt.symbol.companionClass.exists)
-                    registerUseGuarded(None, alt.symbol.companionClass, sel.imported.span, tree.source)
+                  try
+                    if (alt.symbol.companionClass.exists)
+                      registerUseGuarded(None, alt.symbol.companionClass, sel.imported.span, tree.source)
+                  catch case ex: StaleSymbol =>
+                    // can happen for constructor proxies. Test case is pos-macros/i13532.
+                    ()
+
         case tree: Inlined =>
           traverse(tree.call)
         case tree: TypeTree =>

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

@@ -691,7 +691,8 @@ class Namer { typer: Typer =>
               for moduleSym <- companionVals do
                 if moduleSym.is(Module) && !moduleSym.isDefinedInCurrentRun then
                   val companion =
-                    if needsConstructorProxies(classSym) then classConstructorCompanion(classSym.asClass)
+                    if needsConstructorProxies(classSym) then
+                      classConstructorCompanion(classSym.asClass)
                     else newModuleSymbol(
                       ctx.owner, moduleName, EmptyFlags, EmptyFlags, (_, _) => NoType)
                   enterSymbol(companion)

tests/pos/i13532/Bar.scala

@@ -0,0 +1,7 @@
+package testcode
+
+import testcode.Foo
+
+class Bar(f: Foo) {
+	TestMacro.call()
+}

tests/pos/i13532/Foo.scala

@@ -0,0 +1,5 @@
+package testcode
+
+class Foo {
+	TestMacro.call()
+}

tests/pos/i13532/TestMacro.scala

@@ -0,0 +1,8 @@
+package testcode
+
+import scala.quoted.Quotes
+
+object TestMacro {
+    private def impl()(using Quotes) = '{ 123 }
+    inline def call(): Int = ${ impl() }
+}