[Qemu-devel] Re: SIGSEGV on Windows with KQEMU enabled

[Consul]

Johannes Schindelin wrote:

> compiling with --std=c99?

with -std=c99 it does not even compile

> Alternatively, you might want to try to
>
> #define snprintf __mingw_snprintf
> #define vsnprintf __mingw_vsnprintf

These give linker undefined symbol errors.

But really funny think is the change that triggers the bug is precisely this:
-Monitor *cur_mon;
+Monitor *cur_mon = NULL;

Obviously, kqemu is happier having garbage in the cur_mon than NULL


> in a central place.
>
> Explanation: M$' C runtime is not C99 compliant.  It interprets %llu to 
> mean "unsigned long", not "unsigned long long".  As a consequence, the 
> bitwidths of the parameters are interpreted wrong, so that pointers after 
> that parameter point anywhere but the correct address.
>
> As far as I can tell, TDM's GCC works around most of the issue, but forgot 
> snprintf and vsnprintf.
>
> You might also be interested in this:
>
> https://sourceforge.net/tracker/index.php?func=detail&aid=2671742&group_id=200665&atid=974439
>
> Hth,
> Dscho