#include <llvm/ADT/SmallVectorExtras.h>

int main()
{
    int data[] = {1,2,3,4,5};
    bool changed = false;
    auto fn = [&](int val) { changed = true; return val; };
    auto out = llvm::map_to_vector(data, fn);
    return changed;
}

Program should print 1.  However, on GCC 12.* and 13.* for -O1 & -O2, the output is 0.

// Summary of Results
//           -O0    -O1/2  -O3
// 11.*      pass   pass   pass
// 12.*      pass   FAIL   pass 
// 13.*      pass   FAIL   pass
// 14.*      pass   pass   pass