strange rb_gc_mark error

[Elias Athanasopoulos]

Hello!

I have a pure C function, which may be called arbitrary
sequential times. If I call any rb_* function inside, including
the simple rb_warn(), I get:

BUG] rb_gc_mark(): unknown data type 0x28(0x89965b0) non object
ruby 1.8.0 (2003-08-04) [i586-linux]

The error occures after a lot of calls; it reminds me the
behaviour of a stack overflow, or something.

The C function is quite simpe:

static double foo (double *x, double *y)
{
double f = 5.000000;

rb_warn ("%f\n", f);

return f;
}

If I remove the rb_warn() call, everything works okay.

Any hints?

Regards,

 

[Yukihiro Matsumoto]

Hi,

In message "strange rb_gc_mark error"

|I have a pure C function, which may be called arbitrary
|sequential times. If I call any rb_* function inside, including
|the simple rb_warn(), I get:
|
|BUG] rb_gc_mark(): unknown data type 0x28(0x89965b0) non object
|ruby 1.8.0 (2003-08-04) [i586-linux]
|
|The error occures after a lot of calls; it reminds me the
|behaviour of a stack overflow, or something.

Show us whole program, if possible, to reproduce your error.

matz.

 

[Elias Athanasopoulos]

Hi,

In message "strange rb_gc_mark error"

|I have a pure C function, which may be called arbitrary
|sequential times. If I call any rb_* function inside, including
|the simple rb_warn(), I get:
|
|BUG] rb_gc_mark(): unknown data type 0x28(0x89965b0) non object
|ruby 1.8.0 (2003-08-04) [i586-linux]
|
|The error occures after a lot of calls; it reminds me the
|behaviour of a stack overflow, or something.

Show us whole program, if possible, to reproduce your error.

I will try, but it is a little bit hard because the C func is called
from a C++ method deeply inside a complex inheritance tree.

Things that I can verify now are:

(a) The C func is called with no problem 8000 times.
(b) The C func is called for 3000+ and segfaults if I put a
simple rb_warn() inside. Ruby 1.8.0
(c) The C func is called for 6000+ and segfaults if I put a
simple rb_warn() inside. Ruby 1.8.1 preview 3.

Regards,

 

[Elias Athanasopoulos]

Hi,

In message "strange rb_gc_mark error"

|I have a pure C function, which may be called arbitrary
|sequential times. If I call any rb_* function inside, including
|the simple rb_warn(), I get:
|
|BUG] rb_gc_mark(): unknown data type 0x28(0x89965b0) non object
|ruby 1.8.0 (2003-08-04) [i586-linux]
|
|The error occures after a lot of calls; it reminds me the
|behaviour of a stack overflow, or something.

Show us whole program, if possible, to reproduce your error.

I will try, but it is a little bit hard because the C func is called
from a C++ method deeply inside a complex inheritance tree.

Things that I can verify now are:

(a) The C func is called with no problem 8000 times.
(b) The C func is called for 3000+ and segfaults if I put a
simple rb_warn() inside. Ruby 1.8.0
(c) The C func is called for 6000+ and segfaults if I put a
simple rb_warn() inside. Ruby 1.8.1 preview 3.

Okay, it is my fault. :-(

While writting a C++ extension for Ruby, I do (almost everywhere):

static VALUE foo_init (...)
{
Foo *f = new Foo();
rb_iv_set (self, "__ptr__", (VALUE) f);
return self;
}

static VALUE foo_bar (...)
{
Foo *f = (Foo *) rb_iv_get (self, "__ptr__");
f->Bar();
return self;
}

The error ruby reports is on an address of a Foo created pointer.
If I remove the rb_iv_set() call, ruby executes correctly. But, I
have to keep the pointer somewhere in order to execute methods of
the specific class.

Any ideas?

Regards,

 

[ts]

E> Any ideas?

Use Data_Wrap_Struct


Guy Decoux

 

[Ara.T.Howard]

Date: Sun, 14 Dec 2003 02:33:04 +0900
From: Elias Athanasopoulos <[email protected]>
Newsgroups: comp.lang.ruby
Subject: Re: strange rb_gc_mark error

Hi,

In message "strange rb_gc_mark error"

|I have a pure C function, which may be called arbitrary
|sequential times. If I call any rb_* function inside, including
|the simple rb_warn(), I get:
|
|BUG] rb_gc_mark(): unknown data type 0x28(0x89965b0) non object
|ruby 1.8.0 (2003-08-04) [i586-linux]
|
|The error occures after a lot of calls; it reminds me the
|behaviour of a stack overflow, or something.

Show us whole program, if possible, to reproduce your error.

I will try, but it is a little bit hard because the C func is called
from a C++ method deeply inside a complex inheritance tree.

Things that I can verify now are:

(a) The C func is called with no problem 8000 times.
(b) The C func is called for 3000+ and segfaults if I put a
simple rb_warn() inside. Ruby 1.8.0
(c) The C func is called for 6000+ and segfaults if I put a
simple rb_warn() inside. Ruby 1.8.1 preview 3.

Okay, it is my fault. :-(

While writting a C++ extension for Ruby, I do (almost everywhere):

static VALUE foo_init (...)
{
Foo *f = new Foo();
rb_iv_set (self, "__ptr__", (VALUE) f);
return self;
}

static VALUE foo_bar (...)
{
Foo *f = (Foo *) rb_iv_get (self, "__ptr__");
f->Bar();
return self;
}

The error ruby reports is on an address of a Foo created pointer.
If I remove the rb_iv_set() call, ruby executes correctly. But, I
have to keep the pointer somewhere in order to execute methods of
the specific class.

Any ideas?

create a struct to wrap Foo objects with and let ruby handle the object:

struct FooWrap { Foo *foo; };
...
...
VALUE rb_cFooWrap;
...
...
static VALUE
FooWrap_free (FooWrap)
struct FooWrap *FooWrap;
{
delete FooWrap->foo;
free(FooWrap);
}
...
...
/* defined this as the class 'new' method in Init */
static VALUE
rb_cFooWrap_c_new (klass)
VALUE klass;
{
struct FooWrap *FooWrap;
VALUE obj;
obj = Data_Make_Struct(klass, struct FooWrap, 0, FooWrap_free, FooWrap);
return obj;
}
...
...
static VALUE foo_init (...)
{
rb_iv_set (self, "foowrap", rb_cFooWrap_c_new);
return self;
}

static VALUE foo_bar (...)
{
VALUE foowrap;
struct FooWrap *FooWrap;

foowrap = rb_iv_get (self, "foowrap");
Data_Get_Struct(foowrap, struct FooWrap, FooWrap)
FooWrap->foo->Bar();
return self;
}


i don't know if you can wrap c++ class directly since Data_Make_Struct uses
ALLOC internally...

-a
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