attempted linux build fix

I am so confused

CMakeLists.txt

@@ -68,6 +68,6 @@ set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -O3")
 if (CMAKE_CXX_COMPILER_ID MATCHES ".*Clang")
     set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -stdlib=libc++ -lc++abi")
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")
-    set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -fsanitize=undefined")
+    set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -stdlib=libc++ -fsanitize=undefined")
     set(PROJECT_WARNINGS ${CLANG_WARNINGS})
 endif ()

quicktex/Color.h

@@ -18,9 +18,8 @@
  */
 
 #pragma once
-#include <assert.h>  // for assert
+#include <cassert>  // for assert
-#include <stddef.h>  // for size_t
+#include <cstddef>  // for size_t
-
 #include <cstdint>  // for uint8_t, uint16_t
 
 namespace quicktex {