diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4080a08143..b475b2ac5b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -70,12 +70,6 @@ function (ADD_CHECK_CXX_COMPILER_FLAG _CXXFLAGS _CACHE_VAR _FLAG)
     endif ()
 endfunction ()
 
-ADD_CHECK_C_COMPILER_FLAG(CMAKE_C_FLAGS C_WARN_MISSING_VARIABLE_DECLARATIONS -Wmissing-variable-declarations)
-ADD_CHECK_C_COMPILER_FLAG(CMAKE_C_FLAGS C_WARN_DUPLICATED_COND -Wduplicated-cond)
-ADD_CHECK_C_COMPILER_FLAG(CMAKE_C_FLAGS C_WARN_DUPLICATED_BRANCHES -Wduplicated-branches)
-ADD_CHECK_C_COMPILER_FLAG(CMAKE_C_FLAGS C_WARN_LOGICAL_OP -Wlogical-op)
-ADD_CHECK_C_COMPILER_FLAG(CMAKE_C_FLAGS C_WARN_RESTRICT -Wrestrict)
-ADD_CHECK_C_COMPILER_FLAG(CMAKE_C_FLAGS C_WARN_UNREACHABLE_CODE_BREAK -Wunreachable-code-break)
 ADD_CHECK_CXX_COMPILER_FLAG(CMAKE_CXX_FLAGS CXX_WARN_NULL_DEREFERENCE -Wnull-dereference)
 ADD_CHECK_CXX_COMPILER_FLAG(CMAKE_CXX_FLAGS CXX_WARN_SUGGEST_FINAL_TYPES -Wsuggest-final-types)
 ADD_CHECK_CXX_COMPILER_FLAG(CMAKE_CXX_FLAGS CXX_WARN_SUGGEST_FINAL_METHODS -Wsuggest-final-methods)
diff --git a/src/openrct2/CMakeLists.txt b/src/openrct2/CMakeLists.txt
index e6a9a187b2..81fc94450f 100644
--- a/src/openrct2/CMakeLists.txt
+++ b/src/openrct2/CMakeLists.txt
@@ -50,8 +50,7 @@ if (NOT DISABLE_TTF)
 endif ()
 
 # Sources
-file(GLOB_RECURSE OPENRCT2_CORE_SOURCES "${CMAKE_CURRENT_LIST_DIR}/*.c"
-                                        "${CMAKE_CURRENT_LIST_DIR}/*.cpp"
+file(GLOB_RECURSE OPENRCT2_CORE_SOURCES "${CMAKE_CURRENT_LIST_DIR}/*.cpp"
                                         "${CMAKE_CURRENT_LIST_DIR}/*.h"
                                         "${CMAKE_CURRENT_LIST_DIR}/*.hpp")
 if (APPLE)