new Functiontemplates ends in Segfault

[t...@ainfach.de]

Hi,

i try to extend v8 and everytime i end up in a segmentation fault.

here is the code:

https://gist.github.com/anonymous/54334744f14864c9b242#file-gistfile1-cpp-L69

Line 69 ends up in a segmentation fault (debugged using GCC) but i have no idea why.

here is my gdb output:

Breakpoint 1 at 0x56afee: file /home/dev/proj/cpp/v8example/modul_point.cc, line 61.

(gdb) c

Continuing.

[New Thread 0x7f61b7c3e700 (LWP 16397)]

[New Thread 0x7f61b7c23700 (LWP 16398)]

[New Thread 0x7f61b7c12700 (LWP 16399)]

[New Thread 0x7f61b7c01700 (LWP 16400)]

Breakpoint 1, modul_point::addToV8Scope (scope=0x7fffd1594d30) at /home/dev/proj/cpp/v8example/modul_point.cc:61

61 tpl->InstanceTemplate()->SetInternalFieldCount(1);

(gdb) n

67 Local<String> s = String::NewSymbol("getPosX");

(gdb) 

68 Local<FunctionTemplate> f = FunctionTemplate::New(&getPosX);

(gdb) s

Handle (this=<optimized out>) at /home/dev/Downloads/v8/include/v8.h:242

242  V8_INLINE(Handle()) : val_(0) {}

(gdb) 

modul_point::addToV8Scope (scope=0x7fffd1594d30) at /home/dev/proj/cpp/v8example/modul_point.cc:68

68 Local<FunctionTemplate> f = FunctionTemplate::New(&getPosX);

(gdb) 

69 Local<Function> fi = f->GetFunction();

(gdb) p *f

Could not find operator*.

(gdb) p f

$1 = {<v8::Handle<v8::FunctionTemplate>> = {val_ = 0x16178f0}, <No data fields>}

(gdb) p f

$2 = {<v8::Handle<v8::FunctionTemplate>> = {val_ = 0x16178f0}, <No data fields>}

(gdb) p Handle

No symbol "Handle" in current context.

(gdb) p f

$3 = {<v8::Handle<v8::FunctionTemplate>> = {val_ = 0x16178f0}, <No data fields>}

(gdb) p f.val_

$4 = (v8::FunctionTemplate *) 0x16178f0

(gdb) p *f.val_

$5 = {<v8::Template> = {<v8::Data> = {<No data fields>}, <No data fields>}, <No data fields>}

(gdb) p f.val_

$6 = (v8::FunctionTemplate *) 0x16178f0

(gdb) n

Program received signal SIGSEGV, Segmentation fault.

0x00000000006a6db5 in v8::internal::Isolate::native_context() ()

is it up to: V8_INLINE(Handle()) : val_(0) {} ?

[t...@ainfach.de]

here is the complete project https://github.com/timglabisch/jsfastcgi/blob/master/modul_point.cc#L95

at line 95 i get the segfault.

hope somebody could help me.

[Stephan Beal]

On Thu, May 23, 2013 at 9:11 PM, t...@ainfach.de <t...@ainfach.de> wrote:

here is the complete project https://github.com/timglabisch/jsfastcgi/blob/master/modul_point.cc#L95

at line 95 i get the segfault.

hope somebody could help me.

This is just a wild guess, but what happens if you remove the HandleScope?

Also, you shouldn't generally be passing around (Handle<T>*), but should pass around (Handle<T> const &) instead (but that's not the cause of your problem).

--
----- stephan beal
http://wanderinghorse.net/home/stephan/

http://gplus.to/sgbeal

[t...@ainfach.de]

Thanks for your reply!

if i remove the handleScope i stll have the same issue, i rewrote some lines, but it didnt help. getFunction() still cause a segfault.

https://github.com/timglabisch/jsfastcgi/blob/master/modul_point.cc#L93