This is being emitted with [GCC 10.2.1](https://packages.debian.org/bullseye/g++-arm-linux-gnueabihf), in some CI jobs: i.e https://github.com/bitcoin/bitcoin/pull/25972/checks?check_run_id=12423693655, or https://github.com/bitcoin/bitcoin/pull/25972/checks?check_run_id=12423693651 (where we actually turn on all our warning flags with depends builds).
```bash
In file included from test/miniscript_tests.cpp:19:
./script/miniscript.h:1197:71: error: comparison of integers of different signs: 'typename iterator_traits<int *>::difference_type' (aka 'int') and 'const uint32_t' (aka 'const unsigned int') [-Werror,-Wsign-compare]
                    return std::count(subs.begin(), subs.end(), true) >= node.k;
                           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^  ~~~~~~
test/miniscript_tests.cpp:346:34: note: in instantiation of function template specialization 'miniscript::Node<CPubKey>::IsSatisfiable<(lambda at test/miniscript_tests.cpp:346:48)>' requested here
        bool satisfiable = node->IsSatisfiable([](const Node&) { return true; });
                                 ^
1 error generated.
```

cc @darosior 
uint32_t GetOps() const { return ops.count + ops.sat.value; }
    
    uint32_t GetStaticOps() const { return ops.count; }
    
    bool CheckOpsLimit() const { return GetOps() <= MAX_OPS_PER_SCRIPT; }
    /** Return the maximum number of stack elements needed to satisfy this script non-malleably, including
     * the script push. */
    uint32_t GetStackSize() const { return ss.sat.value + 1; }
    
    bool CheckStackSize() const { return GetStackSize() - 1 <= MAX_STANDARD_P2WSH_STACK_ITEMS; }
    
    Type GetType() const { return typ; }
    
    const Node* FindInsaneSub() const {
        return TreeEval<const Node*>([](const Node& node, Span<const Node*> subs) -> const Node* {
            for (auto& sub: subs) if (sub) return sub;
            if (!node.IsSaneSubexpression()) return &node;
            return nullptr;
        });
    }
    
    
    template<typename F>
    bool IsSatisfiable(F fn) const