diff --git a/src/utils.h b/src/utils.h
index 43927381..60ad46e9 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -130,17 +130,24 @@ safe_isnan(double a) {
 		(uint32_t) __to_tmp;                                                     \
 	})
 
+/* Are two types/vars the same type (ignoring qualifiers)? */
+#define is_same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b))
+
 /**
  * container_of - cast a member of a structure out to the containing structure
  * @ptr:	the pointer to the member.
  * @type:	the type of the container struct this is embedded in.
  * @member:	the name of the member within the struct.
  *
+ * WARNING: any const qualifier of @ptr is lost.
  */
 #define container_of(ptr, type, member)                                                  \
 	({                                                                               \
-		const __typeof__(((type *)0)->member) *__mptr = (ptr);                   \
-		(type *)((char *)__mptr - offsetof(type, member));                       \
+		void *__mptr = (void *)(ptr);                                            \
+		static_assert(is_same_type(*(ptr), ((type *)0)->member) ||               \
+		                  is_same_type(*(ptr), void),                            \
+		              "pointer type mismatch in container_of()");                \
+		((type *)(__mptr - offsetof(type, member)));                             \
 	})
 
 /**