Dump more info before crashing.

runtime/vm/object.cc

Index: runtime/vm/object.cc
diff --git a/runtime/vm/object.cc b/runtime/vm/object.cc
index 145791fdc209d4d1beda8287491bc1fc5c2bff52..33cb344bd4698ea7c22bb47507b844880f86de3f 100644
--- a/runtime/vm/object.cc
+++ b/runtime/vm/object.cc
@@ -6418,23 +6418,6 @@ bool Function::TestParameterType(
     Heap::Space space) const {
   AbstractType& other_param_type =
       AbstractType::Handle(other.ParameterTypeAt(other_parameter_position));
-
-  // TODO(regis): Remove this debugging code.
-  if (other_param_type.IsNull()) {
-    const Class& owner = Class::Handle(Owner());
-    const Class& other_owner = Class::Handle(other.Owner());
-    THR_Print("*** null other_param_type ***\n");
-    THR_Print("parameter_position: %" Pd "\n", parameter_position);
-    THR_Print("other_parameter_position: %" Pd "\n", other_parameter_position);
-    THR_Print("function: %s\n", ToCString());
-    THR_Print("function owner: %s\n", owner.ToCString());
-    THR_Print("other function: %s\n", other.ToCString());
-    THR_Print("other function owner: %s\n", other_owner.ToCString());
-    AbstractType& param_type =
-        AbstractType::Handle(ParameterTypeAt(parameter_position));
-    THR_Print("param_type: %s\n", param_type.ToCString());
-  }
-
   if (!other_param_type.IsInstantiated()) {
     other_param_type =
         other_param_type.InstantiateFrom(other_type_arguments,
@@ -6452,16 +6435,40 @@ bool Function::TestParameterType(
 
   // TODO(regis): Remove this debugging code.
   if (param_type.IsNull()) {
-    const Class& owner = Class::Handle(Owner());
-    const Class& other_owner = Class::Handle(other.Owner());
     THR_Print("*** null param_type ***\n");
     THR_Print("parameter_position: %" Pd "\n", parameter_position);
     THR_Print("other_parameter_position: %" Pd "\n", other_parameter_position);
-    THR_Print("function: %s\n", ToCString());
+    String& str = String::Handle();
+    str = QualifiedScrubbedName();
+    THR_Print("function name: %s\n", str.ToCString());
+    str = other.QualifiedScrubbedName();
+    THR_Print("other function name: %s\n", str.ToCString());
+    Class& owner = Class::Handle();
+    owner = Owner();
     THR_Print("function owner: %s\n", owner.ToCString());
-    THR_Print("other function: %s\n", other.ToCString());
-    THR_Print("other function owner: %s\n", other_owner.ToCString());
+    owner = other.Owner();
+    THR_Print("other function owner: %s\n", owner.ToCString());
     THR_Print("other_param_type: %s\n", other_param_type.ToCString());
+    AbstractType& type = AbstractType::Handle();
+    if (parameter_position > 0) {
+      type = ParameterTypeAt(0);
+      THR_Print("receiver type: %s\n",
+                type.IsNull()? "null" : type.ToCString());
+    }
+    THR_Print("has code: %s\n", HasCode() ? "yes" : "no");
+    str = Report::PrependSnippet(Report::kWarning,
+                                 Script::Handle(script()),
+                                 token_pos(),
+                                 Report::AtLocation,
+                                 Symbols::Empty());
+    THR_Print("function source: %s\n", str.ToCString());
+    for (intptr_t i = 0; i < NumParameters(); i++) {
+      THR_Print("function param %" Pd "\n", i);
+      str = ParameterNameAt(i);
+      THR_Print("  name: %s\n", str.IsNull() ? "null" : str.ToCString());
+      type = ParameterTypeAt(i);
+      THR_Print("  type: %s\n", type.IsNull() ? "null" : type.ToCString());
+    }
   }
 
   if (!param_type.IsInstantiated()) {