commit f9c8f3c920ecad0f982715966bc230630c500069
author Alexander Markov <alexmarkov@google.com> Wed Aug 04 22:59:09 2021 +0000
committer commit-bot@chromium.org <commit-bot@chromium.org> Wed Aug 04 22:59:09 2021 +0000
tree 9fc52b28801d8de1b9d466cc2ea7ecd78a2eb685
parent 32914654bd3a2a927347ab5019f3c7f20f49b337

[vm] Fix equality of implicit static closures

There could be multiple instances of implicit static closures due to
instantiations at run time:

void foo<T>(T x) {}

void bar<T>() {
  void Function(T) myfoo1 = foo;
  void Function(T) myfoo2 = foo;
  print(myfoo1 == myfoo2);
}

This change fixes equality to handle this case.

TEST=language/generic_methods/explicit_instantiated_tearoff_test
TEST=language/constructor/tear_off_test

Issue https://github.com/dart-lang/sdk/issues/46231
Issue https://github.com/dart-lang/sdk/issues/46487

Change-Id: I485acc5444d19860ef4d8ebeec2e540fe57776d6
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/208981
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>

runtime/lib/function.cc

diff --git a/runtime/lib/function.cc b/runtime/lib/function.cc
index 53ff1e6..eebce6d 100644
--- a/runtime/lib/function.cc
+++ b/runtime/lib/function.cc
@@ -50,24 +50,28 @@
   }
   // Closures that are not implicit instance closures are unique.
   const auto& func_a = Function::Handle(zone, receiver.function());
-  if (!func_a.IsImplicitInstanceClosureFunction()) {
+  if (!func_a.IsImplicitClosureFunction()) {
     return false;
   }
   const auto& func_b = Function::Handle(zone, other_closure.function());
-  if (!func_b.IsImplicitInstanceClosureFunction()) {
+  if (!func_b.IsImplicitClosureFunction()) {
     return false;
   }
   // If the closure functions are not the same, check the function's name and
   // owner, as multiple function objects could exist for the same function due
   // to hot reload.
   if (func_a.ptr() != func_b.ptr() &&
-      (func_a.name() != func_b.name() || func_a.Owner() != func_b.Owner())) {
+      (func_a.name() != func_b.name() || func_a.Owner() != func_b.Owner() ||
+       func_a.is_static() != func_b.is_static())) {
     return false;
   }
-  // Check that the both receiver instances are the same.
-  const Context& context_a = Context::Handle(zone, receiver.context());
-  const Context& context_b = Context::Handle(zone, other_closure.context());
-  return context_a.At(0) == context_b.At(0);
+  if (!func_a.is_static()) {
+    // Check that the both receiver instances are the same.
+    const Context& context_a = Context::Handle(zone, receiver.context());
+    const Context& context_b = Context::Handle(zone, other_closure.context());
+    return context_a.At(0) == context_b.At(0);
+  }
+  return true;
 }
 
 DEFINE_NATIVE_ENTRY(Closure_equals, 0, 2) {