cat > /tmp/t.cpp <<'CPP'
#include <bits/stdc++.h>
using namespace std;
int main(){ vector<int> v={1,2,3}; int s=0; for(int x:v) s+=x; cout<<s<<"\n"; }
CPP
cat /tmp/t.cpp; ls -l /tmp/t.cpp; clang++ -O2 -o /tmp/t /tmp/t.cpp; echo compile=$?; /tmp/t; echo run=$?