diff --git a/src/macros.rs b/src/macros.rs
index 1408384..929e2d7 100644
--- a/src/macros.rs
+++ b/src/macros.rs
@@ -6,48 +6,54 @@ macro_rules! cstr {
 
 // A panic that clears the given lua stack before panicking
 macro_rules! lua_panic {
-    ($state:expr) => {
-        {
-            $crate::ffi::lua_settor($state, 0);
-            panic!("rlua internal error");
-        }
-    };
-
     ($state:expr, $msg:expr) => {
         {
             $crate::ffi::lua_settop($state, 0);
-            panic!(concat!("rlua internal error: ", $msg));
+            panic!($msg);
         }
     };
 
-    ($state:expr, $fmt:expr, $($arg:tt)+) => {
+    ($state:expr, $msg:expr, $($arg:tt)+) => {
         {
             $crate::ffi::lua_settop($state, 0);
-            panic!(concat!("rlua internal error: ", $fmt), $($arg)+);
+            panic!($msg, $($arg)+);
         }
     };
 }
 
 // An assert that clears the given lua stack before panicking
 macro_rules! lua_assert {
-    ($state:expr, $cond:expr) => {
-        if !$cond {
-            $crate::ffi::lua_settop($state, 0);
-            panic!("rlua internal error");
-        }
-    };
-
     ($state:expr, $cond:expr, $msg:expr) => {
         if !$cond {
             $crate::ffi::lua_settop($state, 0);
-            panic!(concat!("rlua internal error: ", $msg));
+            panic!($msg);
         }
     };
 
-    ($state:expr, $cond:expr, $fmt:expr, $($arg:tt)+) => {
+    ($state:expr, $cond:expr, $msg:expr, $($arg:tt)+) => {
         if !$cond {
             $crate::ffi::lua_settop($state, 0);
-            panic!(concat!("rlua internal error: ", $fmt), $($arg)+);
+            panic!($msg, $($arg)+);
         }
     };
 }
+
+macro_rules! lua_internal_panic {
+    ($state:expr, $msg:expr) => {
+        lua_panic!($state, concat!("rlua internal error: ", $msg));
+    };
+
+    ($state:expr, $msg:expr, $($arg:tt)+) => {
+        lua_panic!($state, concat!("rlua internal error: ", $msg), $($arg)+);
+    };
+}
+
+macro_rules! lua_internal_assert {
+    ($state:expr, $cond:expr, $msg:expr) => {
+        lua_assert!($state, $cond, concat!("rlua internal error: ", $msg));
+    };
+
+    ($state:expr, $cond:expr, $msg:expr, $($arg:tt)+) => {
+        lua_assert!($state, $cond, concat!("rlua internal error: ", $msg), $($arg)+);
+    };
+}
diff --git a/src/userdata.rs b/src/userdata.rs
index 536c853..8c7a92f 100644
--- a/src/userdata.rs
+++ b/src/userdata.rs
@@ -370,7 +370,7 @@ impl<'lua> AnyUserData<'lua> {
 
                 lua.push_ref(lua.state, &self.0);
 
-                lua_assert!(
+                lua_internal_assert!(
                     lua.state,
                     ffi::lua_getmetatable(lua.state, -1) != 0,
                     "AnyUserData missing metatable"
diff --git a/src/util.rs b/src/util.rs
index aba6ba6..9789d02 100644
--- a/src/util.rs
+++ b/src/util.rs
@@ -11,7 +11,7 @@ use error::{Error, Result};
 // Checks that Lua has enough free stack space for future stack operations.
 // On failure, this will clear the stack and panic.
 pub unsafe fn check_stack(state: *mut ffi::lua_State, amount: c_int) {
-    lua_assert!(
+    lua_internal_assert!(
         state,
         ffi::lua_checkstack(state, amount) != 0,
         "out of stack space"
@@ -25,7 +25,7 @@ where
     F: FnOnce() -> R,
 {
     let expected = ffi::lua_gettop(state) + change;
-    lua_assert!(
+    lua_internal_assert!(
         state,
         expected >= 0,
         "too many stack values would be popped"
@@ -34,7 +34,7 @@ where
     let res = op();
 
     let top = ffi::lua_gettop(state);
-    lua_assert!(
+    lua_internal_assert!(
         state,
         ffi::lua_gettop(state) == expected,
         "expected stack to be {}, got {}",
@@ -59,7 +59,7 @@ where
     F: FnOnce() -> Result<R>,
 {
     let expected = ffi::lua_gettop(state) + change;
-    lua_assert!(
+    lua_internal_assert!(
         state,
         expected >= 0,
         "too many stack values would be popped"
@@ -69,7 +69,7 @@ where
 
     let top = ffi::lua_gettop(state);
     if res.is_ok() {
-        lua_assert!(
+        lua_internal_assert!(
             state,
             ffi::lua_gettop(state) == expected,
             "expected stack to be {}, got {}",
@@ -77,7 +77,7 @@ where
             top
         );
     } else {
-        lua_assert!(
+        lua_internal_assert!(
             state,
             top >= expected,
             "{} too many stack values popped",
@@ -171,7 +171,7 @@ where
 // the current lua stack and continues the panic.  If the error on the top of the stack is actually
 // a WrappedError, just returns it.  Otherwise, interprets the error as the appropriate lua error.
 pub unsafe fn pop_error(state: *mut ffi::lua_State, err_code: c_int) -> Error {
-    lua_assert!(
+    lua_internal_assert!(
         state,
         err_code != ffi::LUA_OK && err_code != ffi::LUA_YIELD,
         "pop_error called with non-error return code"
@@ -185,7 +185,7 @@ pub unsafe fn pop_error(state: *mut ffi::lua_State, err_code: c_int) -> Error {
             ffi::lua_settop(state, 0);
             resume_unwind(p);
         } else {
-            lua_panic!(state, "panic was resumed twice")
+            lua_internal_panic!(state, "panic was resumed twice")
         }
     } else {
         let err_string = gc_guard(state, || {
@@ -221,7 +221,7 @@ pub unsafe fn pop_error(state: *mut ffi::lua_State, err_code: c_int) -> Error {
                 process::abort()
             }
             ffi::LUA_ERRGCMM => Error::GarbageCollectorError(err_string),
-            _ => lua_panic!(state, "unrecognized lua error code"),
+            _ => lua_internal_panic!(state, "unrecognized lua error code"),
         }
     }
 }
@@ -244,7 +244,7 @@ pub unsafe fn push_userdata<T>(state: *mut ffi::lua_State, t: T) -> Result<()> {
 // Returns None in the case that the userdata has already been garbage collected.
 pub unsafe fn get_userdata<T>(state: *mut ffi::lua_State, index: c_int) -> *mut T {
     let ud = ffi::lua_touserdata(state, index) as *mut T;
-    lua_assert!(state, !ud.is_null(), "userdata pointer is null");
+    lua_internal_assert!(state, !ud.is_null(), "userdata pointer is null");
     ud
 }