Program received SIGSEGV - invalid memory reference - windows

Question

I wrote a small linker in fortran-cpp to read a file with some numbers.
$cat mainProg.f
program fprogram
real*8 c(30)
do i=1,30
c(i) = i * 1.0
end do
print*,"Before calling cpp function"
c PASS ARRAY "C" TO CPP
call pass_to_cpp(c)
print*,"After calling cpp function"
do i=1,30
print*,' c =',c(i)
end do
print*,"I'm done here ..!!"
c stop
end
and,
$cat cprog.C
#include<iostream>
#include<cmath>
#include<fstream>
using namespace std;
extern "C" {
void pass_to_cpp_(double *c);
}
void pass_to_cpp_(double *c)
{
ifstream myfile ("example.txt");
for(int i=0; i<30; i++)
{
myfile >> c[i];
cout <<"called = " << i << "\n";
}
}
I am building this on ubuntu 16.04 to be run on a windows machine. I am usin mingw for compiling.
Here is the error on windows:
called = 0
Program received a signal SIGSEGV: Segmentation fault - invalid memory reference
Backtrace for this error:
#0 ffffffffffffff
#1 ffffffffffffff
#2 ffffffffffffff
#3 ffffffffffffff
#4 ffffffffffffff
#5 ffffffffffffff
#6 ffffffffffffff
#7 ffffffffffffff
#8 ffffffffffffff
#9 ffffffffffffff
#10 ffffffffffffff
#11 ffffffffffffff
#12 ffffffffffffff
#13 ffffffffffffff
#14 ffffffffffffff
#15 ffffffffffffff
File 'example.txt' is a simple file with 30 numbers.
Any suggestions on what is the cause of the error?
I compiled with this:
$ x86_64-w64-mingw32-gfortran -c main_read.f
$ x86_64-w64-mingw32-g++ -c cread.C
$ x86_64-w64-mingw32-gfortran -o read.exe main_read.o cread.o -lstdc++ -static
If I dont use -static, it complains 'libgfortran3.dll not found'.