CI: added more tests

src/merkle.cpp

@@ -26,6 +26,12 @@ namespace p2pool {
 void merkle_hash(const std::vector<hash>& hashes, root_hash& root)
 {
 	const size_t count = hashes.size();
+
+	if (count == 0) {
+		root.clear();
+		return;
+	}
+
 	const uint8_t* h = hashes[0].h;
 
 	if (count == 1) {
@@ -62,10 +68,15 @@ void merkle_hash(const std::vector<hash>& hashes, root_hash& root)
 void merkle_hash_full_tree(const std::vector<hash>& hashes, std::vector<std::vector<hash>>& tree)
 {
 	const size_t count = hashes.size();
-	const uint8_t* h = hashes[0].h;
 
 	tree.clear();
 
+	if (count == 0) {
+		return;
+	}
+
+	const uint8_t* h = hashes[0].h;
+
 	if (count == 1) {
 		tree.push_back(hashes);
 	}

src/util.h

@@ -175,6 +175,8 @@ template<> FORCEINLINE bool out_of_range<uint64_t>(uint64_t) { return false; }
 template<typename T>
 const uint8_t* readVarint(const uint8_t* data, const uint8_t* data_end, T& b)
 {
+	static_assert(std::is_unsigned_v<T>, "readVarint works only with unsigned types");
+
 	uint64_t result = 0;
 	int k = 0;