segmentation fault on GiNaC-1.2.0 using MinGW on Win XP

[Johannes Brunen]

Hi,

I'm not subscribed to this list, but I have detected a problem with the new release of GiNaC, which I would like to report.

After properly building GiNaC-1.2.0 on windows XP using the MinGW / MSYS platform I got a segmentation fault on
starting my demo application. This didn't happen with GiNaC-1.1.7.

After looking to the source code I found a problem with the current implementation:

In file uitils.cpp the following constants are defined:
_num0_p
_num0
_ex0

These are initialized on behalf of constructor library_init() which is called by statement
static library_init library_initialize from file ex.h (line 53).

The constructor  function_options::function_options(std::string const & n, std::string const & tn)
in file function.cpp (line 56) calls function initialize() (line 67 )which has a statement 
symtree = 0; in its implementation (line 82).

Symtree is of type ex which is initialized by ex(int) which calls 
basic & ex::construct_from_int(int i) in file ex.cpp (line 329).
The relevant line is case 0: return const_cast<numeric &>(_num0);

Reference counting, now, forces usage of operator-> on the _num0 object.
Now, here is the problem: It may happen that the construtor of function_options() is called before
the call of library_init(). 
function_options() is called during registration of class container by statement
GINAC_DECLARE_REGISTERED_CLASS(container, basic) in file container.h (line 130).

The construction order of static objects in different translation units is undefined in C++. Therefore
the problem may or may not show up.

With kind regards and a lot of respect

Johannes