Segfault

[lmangani]

We have two version of this extension:

Working Example

main: the main branch contains a version based on a table function.

It invokes wvlet functions correctly, converts input to SQL and returns results:

D select * from wvlet('from [[1]] as numbers(a)');
-- wvlet version=0.0.0+1-d1d99f7b, src=01JEVTWDECV00NJH6Z93KYQE8J.wv:1
select * from (values (1)) as numbers(a)
┌───────┐
│   a   │
│ int32 │
├───────┤
│     1 │
└───────┘

string query = input[i].GetString();
        std::string json = "[\"-q\", \"" + query + "\"]";
        
        const char* sql_result = wvlet_compile_query(json.c_str());

Failing Example

query-planner: this branch contains a query planner version.

Same library, same functions. In this version, invoking wvlet causes a segfault when trying to convert to SQL, before even attempting to return data into DuckDB:

D from [[1]] as numbers(a);
segfault

The code is essentially the same, and the passed types are correct.

  std::string json = "[\"-q\", \"" + query + "\"]";
  wvlet_compile_main(json.c_str());
  const char* sql_result = wvlet_compile_query(json.c_str());
  if (!sql_result || strlen(sql_result) == 0) {
    throw std::runtime_error("Failed to compile wvlet script");
  }

⚠️ Tracing shows the library segfaults while trying to dereference a null pointer.