Problem Converting Code Using std::vectors to MLIR

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I am trying to compile a simple gather function using vectors for data storage using the compilation flag
```
cgeist $1 -O0 -g -fopenmp -S -o $fileBase.affine.mlir -I/usr/lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11 \
-I/usr/lib/gcc/x86_64-linux-gnu/11/../../../../include/x86_64-linux-gnu/c++/11 \
-I/usr/lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/backward \
-I/home/$USER_NAME/$PROJECT_NAME/build/lib/clang/18/include \
-I/usr/local/include \
-I/usr/include -D$4
```

The function that I'm trying to compile is
```cpp
#include
#include

#pragma scop
void gather_vec(std::vector &a,
std::vector &b,
std::vector &idx) {
for (size_t i = 0; i < idx.size(); ++i) {
a[i] = b[idx[i]];
}
}

int main() {
std::vector a;
std::vector b = {1, 2, 3, 4};
std::vector idx = {3, 2, 1, 0};

gather_vec(a, b, idx);

// verification
for (size_t i = 0; i < a.size(); ++i) {
std::cout << "a[" << i << "] = " << a[i] << "\n";
}

return 0;
}
```
and when I run the cgeist command, I get some cleanup not handled and this error before printing out the intermediate MLIR. I have also attached the whole log.

[cgeist_error.txt](https://github.com/user-attachments/files/20144002/cgeist_error.txt)

Start by reproducing the cgeist command with the shown gather_vec example and inspect cgeist_error.txt alongside the cleanup diagnostic. Trace the vector-related conversion and cleanup handling until the source either emits intermediate MLIR or reports a precise unsupported construct, then add or update coverage if the relevant test location is identified.

Written by the indexing model from the issue text.