diff --git a/CMakeLists.txt b/CMakeLists.txt
index eceb1c2..ea25230 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -92,12 +92,7 @@ if(NOT APPLE AND CMAKE_OBJCOPY)
       $<TARGET_FILE:${PROJECT_NAME}_static>)
 endif()
 
-set(TEST_FLAGS -Wall -Wextra -Wunreachable-code -UNDEBUG)
-
-if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
-  list(APPEND TEST_FLAGS -Wpedantic -Wno-gnu-anonymous-struct
-       -Wno-nested-anon-types)
-endif()
+set(TEST_FLAGS -Wall -Wextra -Wunreachable-code -Wpedantic -UNDEBUG)
 
 include(CTest)
 
diff --git a/ConflictSet.cpp b/ConflictSet.cpp
index 76e8ca6..e7eed08 100644
--- a/ConflictSet.cpp
+++ b/ConflictSet.cpp
@@ -181,6 +181,9 @@ struct Node {
 
   Type type;
 #ifndef NDEBUG
+  // Leaving this uninitialized is intentional and necessary to expect asserts
+  // to pass. Basically it needs to be preserved when going to the free list and
+  // back.
   int32_t partialKeyCapacity;
 #endif
 
@@ -325,6 +328,8 @@ uint8_t *Node::partialKey() {
   case Type::Node256:
     return ((Node256 *)this)->partialKey();
   }
+  __builtin_unreachable();
+  ; // GCOVR_EXCL_LINE
 }
 
 struct NodeAllocators {