dup_statement
struct statement *newstmt = dup_statement(stmt);
stmt = dup_statement(stmt);
stmt = dup_statement(stmt);
stmt = dup_statement(stmt);
stmt = dup_statement(stmt);
stmt = dup_statement(stmt);
stmt = dup_statement(stmt);
stmt = dup_statement(stmt);
stmt = dup_statement(stmt);
stmt = dup_statement(stmt);
stmt = dup_statement(stmt);