On Saturday, 26 January 2013 at 10:52:59 UTC, Rainer Schuetze
wrote:
On 26.01.2013 11:40, Johannes Pfau wrote:
Yes, I just wanted to point out a common source for such bugs,
it's not
the GC's fault. It's great that the documentation of toStringz
mentions
that issue. What I meant is most of the time we use
toStringz() like
this:
string str;
c_function(str.toStringz());
This is only valid if c_function doesn't store the pointer,
but newbies
might miss that and just copy this nice looking example code
for other
c functions. There's nothing we can do about that though,
interfacing
to C just is a little bit dangerous.
It is even dangerous if it is only used temporarily during that
function call, but copied elsewhere in the C heap and cleared
on the stack:
struct param_struct { const char* name; };
void c_function(const char*p)
{
param_struct* ps = new param_struct;
ps->name = p;
p = 0;
doSomething(ps);
delete ps;
}
Imagine a garbage collection while executing doSomething...
That isn't an issue as the pointer will e found at upper level in
the stack anyway.
