> Of course, all this is silly if nested functions carry around their
> lexical scope and can be returned. But I dont know that they do.
A simple test case that would not invoke UB with n1968 lambda functions:
#include <stdio.h>
typedef void (*fn_t)();
void doinvoke(fn_t f)
{
f();
}
fn_t getit(int j)
{
int i=j;
void myfn()
{
printf("Doit. I dare you: %d\n",i);
}
doinvoke(myfn);
return myfn;
// under n1968, we'd
// return <>()->void{printf("Doit. I dare you: %d\n",i);};
}
int main()
{
fn_t five = getit(5);
fn_t six = getit(6);
fn_t seven = getit(7);
five(); six(); seven();
}
Expected output:
Doit. I dare you: 5
Doit. I dare you: 6
Doit. I dare you: 7
Doit. I dare you: 5
Doit. I dare you: 6
Doit. I dare you: 7
Actual output:
Doit. I dare you: 5
Doit. I dare you: 6
Doit. I dare you: 7
Doit. I dare you: 7
Segmentation fault (core dumped)
