(In reply to Puneet Goel from comment #0)
> Created attachment 1571 [details]
> D and C code files along with makefile
> 
> Trying to call D code from C is resulting in segfault.

Kindly see the attachment to look at the code that segfaults.

Reduced the test case a little:

main.c:
----
extern void initialize();

int main(int argc, char*argv[]) {
  initialize();
  return 0;
}
----

foo.d:
----
extern(C) void initialize() {
  import core.runtime;  
  Runtime.initialize;
  int x;
  auto dg = {x = 2;};
  Runtime.terminate();
}
----

Compiling and running:
----
$ gcc -c main.c
$ dmd foo.d main.o
$ ./foo
Segmentation fault (core dumped)
----

I think the problem is that the memory for the closure is allocated as soon as the initialize function is entered, i.e. before the call to Runtime.initialize.

I cannot reproduce this example. Compiling the reduced test case and running it now leads to graceful program exit.