Re: More pure optimizations

[Ary Borenszweig]

bearophile escribió:

Once that optimization is in place, the reading access to associative arrays too can be marked as 
"pure" so the in the following code h["bar"] is seen as a loop invariant, and 
computed only once before the loop:

import std.c.stdio: printf;

int foo(int[string] h) {
    int x;
    for (int i; i < 100; i++)
        x += h["bar"];
    return x;
}

void main() {
    printf("%d\n", foo(["bar": 42]));
}

What if a different thread modifies h in between the loop?