v8::Script::Compile(v8::String::New(".make.some.syntax.errors"), v8::String::New("main"))->Run() causes segmentation fault

Question

Let say I have this code:

Local<Script> script = Script::Compile(String::New("x1 = 1;"), String::New("main.js"));
printf("before run\n");
script->Run();
printf("after run\n");

Context was created and entered before.
Output of this code is:

before run
after run

Which is as expected. But if put some javascript code into source which contains syntax errors (eg, ".x11 = 1") then output is:

main.js:0: Uncaught SyntaxError: Unexpected token .
before execution.
Segmentation fault (core dumped)

Maybe I should not call Run if compilation has errors but how to check it?

In addition: (code from Getting Starget - Chrome V8 + code with syntax errors = the same thing)

#include <v8.h>

using namespace v8;

int main(int argc, char* argv[]) {  

// Get the default Isolate created at startup.  

Isolate* isolate = Isolate::GetCurrent();  

// Create a stack-allocated handle scope.

HandleScope handle_scope(isolate);  

// Create a new context.  

Handle<Context> context = Context::New(isolate);  

// Here's how you could create a Persistent handle to the context, if needed.  

Persistent<Context> persistent_context(isolate, context); 


// Enter the created context for compiling and  

// running the hello world script.   

Context::Scope context_scope(context);  

// Create a string containing the JavaScript source code.  

Handle<String> source = String::New(".>make.some.syntax.errors<");  

// Compile the source code.  

Handle<Script> script = Script::Compile(source);  

// Run the script to get the result.  

Handle<Value> result = script->Run(); 

// The persistent handle needs to be eventually disposed.  

persistent_context.Dispose();  

// Convert the result to an ASCII string and print it.  

String::AsciiValue ascii(result);  

printf("%s\n", *ascii);  

return 0;

}

Answer 1

Based on v8 source code of samples/process.cc:

  // catch any exceptions the script might throw.
  TryCatch try_catch(GetIsolate());

  // Compile the script and check for errors.
  Local<Script> compiled_script;
  if (!Script::Compile(context, script).ToLocal(&compiled_script)) {
    String::Utf8Value error(GetIsolate(), try_catch.Exception());
    Log(*error);
    // The script failed to compile; bail out.
    return false;
  }

  // Run the script!
  Local<Value> result;
  if (!compiled_script->Run(context).ToLocal(&result)) {
    // The TryCatch above is still in effect and will have caught the error.
    String::Utf8Value error(GetIsolate(), try_catch.Exception());
    Log(*error);
    // Running the script failed; bail out.
    return false;
  }

I hope this is helpfull.

Answer 2

After a some time of headache I found a way around it.

When script compilation is failed it returns nothing to v8::Handle. So, in this case, script.IsEmpty() returns true.

To make this clear I made some modifications in Google's Hello World code:

#include <v8.h>

using namespace v8;

int main(int argc, char* argv[]) {  

// Get the default Isolate created at startup.  

Isolate* isolate = Isolate::GetCurrent();  

// Create a stack-allocated handle scope.

HandleScope handle_scope(isolate);  

// Create a new context.  

Handle<Context> context = Context::New(isolate);  

// Here's how you could create a Persistent handle to the context, if needed.  

Persistent<Context> persistent_context(isolate, context); 


// Enter the created context for compiling and  

// running the hello world script.   

Context::Scope context_scope(context);  

// Create a string containing the JavaScript source code.  

Handle<String> source = String::New(".>no.matter.what.code.is<");  

// Compile the source code.  

Handle<Script> script = Script::Compile(source);  
if(!script.IsEmpty()) // is script compiled ?
{
  // Run the script to get the result.  

  Handle<Value> result = script->Run(); 

  // Convert the result to an ASCII string and print it.  
  String::AsciiValue ascii(result);  

  printf("%s\n", *ascii);  
}

// The persistent handle needs to be eventually disposed.  

persistent_context.Dispose();      

return 0;

}