diff --git a/src/sync.cpp b/src/sync.cpp
index c3312b5a0..9abdedbed 100644
--- a/src/sync.cpp
+++ b/src/sync.cpp
@@ -219,12 +219,15 @@ static bool LockHeld(void* mutex)
     return false;
 }
 
-void AssertLockHeldInternal(const char* pszName, const char* pszFile, int nLine, void* cs)
+template <typename MutexType>
+void AssertLockHeldInternal(const char* pszName, const char* pszFile, int nLine, MutexType* cs)
 {
     if (LockHeld(cs)) return;
     tfm::format(std::cerr, "Assertion failed: lock %s not held in %s:%i; locks held:\n%s", pszName, pszFile, nLine, LocksHeld());
     abort();
 }
+template void AssertLockHeldInternal(const char*, const char*, int, Mutex*);
+template void AssertLockHeldInternal(const char*, const char*, int, RecursiveMutex*);
 
 void AssertLockNotHeldInternal(const char* pszName, const char* pszFile, int nLine, void* cs)
 {
diff --git a/src/sync.h b/src/sync.h
index 0c6f0ef0a..60e5a87ae 100644
--- a/src/sync.h
+++ b/src/sync.h
@@ -52,7 +52,8 @@ void EnterCritical(const char* pszName, const char* pszFile, int nLine, void* cs
 void LeaveCritical();
 void CheckLastCritical(void* cs, std::string& lockname, const char* guardname, const char* file, int line);
 std::string LocksHeld();
-void AssertLockHeldInternal(const char* pszName, const char* pszFile, int nLine, void* cs) ASSERT_EXCLUSIVE_LOCK(cs);
+template <typename MutexType>
+void AssertLockHeldInternal(const char* pszName, const char* pszFile, int nLine, MutexType* cs) ASSERT_EXCLUSIVE_LOCK(cs);
 void AssertLockNotHeldInternal(const char* pszName, const char* pszFile, int nLine, void* cs);
 void DeleteLock(void* cs);
 
@@ -66,7 +67,8 @@ extern bool g_debug_lockorder_abort;
 void static inline EnterCritical(const char* pszName, const char* pszFile, int nLine, void* cs, bool fTry = false) {}
 void static inline LeaveCritical() {}
 void static inline CheckLastCritical(void* cs, std::string& lockname, const char* guardname, const char* file, int line) {}
-void static inline AssertLockHeldInternal(const char* pszName, const char* pszFile, int nLine, void* cs) ASSERT_EXCLUSIVE_LOCK(cs) {}
+template <typename MutexType>
+void static inline AssertLockHeldInternal(const char* pszName, const char* pszFile, int nLine, MutexType* cs) ASSERT_EXCLUSIVE_LOCK(cs) {}
 void static inline AssertLockNotHeldInternal(const char* pszName, const char* pszFile, int nLine, void* cs) {}
 void static inline DeleteLock(void* cs) {}
 #endif