On 23/11/2012, LAMOME Julien CS-SI <julien.lamome-cs-si@xxxxxxx> wrote:
> a minimum code to show the problem :
> toto.F :
> subroutine toto()
> implicit none
> real*8 variable
> common /demof/variable
>
> print*,'Fortran variable=',variable
> end
>
> toto.cc:
> #include <iostream>
> struct {double variable;}demof;
> extern "C" void toto();
> int main()
> {
> demof.variable=3.14159;
> std::cout<<"C++ variable = "<<demof.variable<<std::endl;
> toto();
> return 0;
> }
>
> * Gcc 4.1 give me :
> C++ variable = 3.14159
> Fortran variable= 3.14159000000000
> * Gcc 4.6 give me:
> C++ variable = 3.14159
> Fortran variable= 0.00000000000000
>
> Yours differents solutions work, but I would prefer to use an option to have
> the old behavior. Because, I have 163 files with anonymous strut to modify.
> And, each file require special attention because struct are linked, or not,
> with a COMMON, and COMMON are not necessary include in source, etc.
> So, if it isn't possible to use an option, I will have a lot of work now.
> Else I could modify progressively.
The old behaviour does not conform to the C++ standard.
I don't think there is any option to restore the old non-conforming behaviour.
