Hi Felix,

I have a report internally on a similar internal error which is instigated by optimizations. That should get resolved in a 12.1 update (i.e. C++ Composer XE 2011 future update). However, that's just speculation on my part unless you can send us a preprocessed version of your source file (using -P) along with the compiler options you used. Our Premer Support web site which you should have an account on for free if you have registered your software provides a convenient way for attaching files securely, so please do so if you're interested in following up. Thanks!

I've got an example that triggers it, in a nutshell perform the same assignment twice but differently:

[c]
#include <stdio.h>
#include <string.h>

struct test_s {
int foo;
};

static void
copy_using_memcpy(struct test_s *pto, struct test_s *pfrom)
{
memcpy(pto, pfrom, sizeof(struct test_s));
return;
}

static void
copy_using_deref(struct test_s *pto, struct test_s *pfrom)
{
*pto = *pfrom;
return;
}

int
main(int argc, char *argv[])
{
struct test_s a = {1};
struct test_s b = {0};

/* do the same assignment twice */
copy_using_deref(&b, &a);
copy_using_memcpy(&b, &a);

/* prevent being optimised away */
return b.foo == a.foo;
}
[/c]