Testcase:

#include <stdlib.h>
void f() { exit(0); }
void (*ff)() = f;
void g(int* restrict a) {
    for (int i = 0; i < 1000; ++i) {
        ff();
        *a += 1;
    }
}
void (*gg)(int* restrict) = g;
int main() {
    gg(0);
}

Works with gcc and clang -O0; crashes with clang -O2.

I think LICM is relying too much on "MayThrow" to conclude that function calls will return normally.

Testcase is artificial.