Changes to allow for -O2 compiles on macos in debug builds.

vm/compiler.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/compiler.h"
 
 #include "vm/assembler.h"
 #include "vm/ast_printer.h"
 #include "vm/code_generator.h"
 #include "vm/code_patcher.h"
@@ skipping 67 matching lines @@
         all_nodes[n]->SetIcDataAtId(node_id, ic_data_obj);
       }
     }
     ASSERT(found_node);
   }
 }
 
 
 RawError* Compiler::Compile(const Library& library, const Script& script) {
   Isolate* isolate = Isolate::Current();
-  Error& error = Error::Handle();
   LongJump* base = isolate->long_jump_base();
   LongJump jump;
   isolate->set_long_jump_base(&jump);
   if (setjmp(*jump.Set()) == 0) {
     if (FLAG_trace_compiler) {
       HANDLESCOPE(isolate);
       const String& script_url = String::Handle(script.url());
       // TODO(iposva): Extract script kind.
       OS::Print("Compiling %s '%s'\n", "", script_url.ToCString());
     }
     const String& library_key = String::Handle(library.private_key());
     script.Tokenize(library_key);
     Parser::ParseCompilationUnit(library, script);
+    isolate->set_long_jump_base(base);
+    return Error::null();
   } else {
+    Error& error = Error::Handle();
     error = isolate->object_store()->sticky_error();
     isolate->object_store()->clear_sticky_error();
+    isolate->set_long_jump_base(base);
+    return error.raw();
   }
-  isolate->set_long_jump_base(base);
-  return error.raw();
+  UNREACHABLE();
+  return Error::null();
 }
 
 
 static void InstallUnoptimizedCode(const Function& function) {
   // Disable optimized code.
   ASSERT(function.HasOptimizedCode());
   // Patch entry of optimized code.
   CodePatcher::PatchEntry(Code::Handle(function.CurrentCode()));
   if (FLAG_trace_compiler) {
     OS::Print("--> patching entry 0x%x\n",
@@ skipping 283 matching lines @@
   } else {
     result = isolate->object_store()->sticky_error();
     isolate->object_store()->clear_sticky_error();
   }
   isolate->set_long_jump_base(base);
   return result.raw();
 }
 
 
 }  // namespace dart