diff --git a/CMakeLists.txt b/CMakeLists.txt
index 47a081e75..ab3976aea 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -24,9 +24,7 @@ if (NOT (EXISTS "${CMAKE_SOURCE_DIR}/src/CMakeLists.txt"))
           "``python contrib/cmake/bootstrap.py create``")
 endif()
 
-# This overrides the default flags for the different CMAKE_BUILD_TYPEs
-set(CMAKE_USER_MAKE_RULES_OVERRIDE "${CMAKE_CURRENT_SOURCE_DIR}/cmake/compiler_flags_override.cmake")
-project(Z3 C CXX)
+project(Z3 CXX)
 
 ################################################################################
 # Project version
diff --git a/contrib/cmake/cmake/compiler_flags_override.cmake b/contrib/cmake/cmake/compiler_flags_override.cmake
deleted file mode 100644
index c6005396b..000000000
--- a/contrib/cmake/cmake/compiler_flags_override.cmake
+++ /dev/null
@@ -1,43 +0,0 @@
-# This file overrides the default compiler flags for CMake's built-in
-# configurations (CMAKE_BUILD_TYPE). Most compiler flags should not be set here.
-# The main purpose is to have very fine grained control of the compiler flags.
-if (CMAKE_C_COMPILER_ID)
-  set(_lang C)
-elseif(CMAKE_CXX_COMPILER_ID)
-  set(_lang CXX)
-else()
-  message(FATAL_ERROR "Unknown language")
-endif()
-
-# TODO: The value of doing this is debatable. The flags set here are pretty
-# much the CMake defaults now (they didn't use to be) and makes extra work for
-# us when supporting different compilers. Perhaps we should move the remaining
-# code that sets non-default flags out into the CMakeLists.txt files and remove
-# any overrides here?
-if (("${CMAKE_${_lang}_COMPILER_ID}" MATCHES "Clang") OR ("${CMAKE_${_lang}_COMPILER_ID}" MATCHES "GNU"))
-  # Taken from Modules/Compiler/GNU.cmake
-  set(CMAKE_${_lang}_FLAGS_INIT "")
-  set(CMAKE_${_lang}_FLAGS_DEBUG_INIT "-g -O0")
-  set(CMAKE_${_lang}_FLAGS_MINSIZEREL_INIT "-Os -DNDEBUG")
-  set(CMAKE_${_lang}_FLAGS_RELEASE_INIT "-O3 -DNDEBUG")
-  set(CMAKE_${_lang}_FLAGS_RELWITHDEBINFO_INIT "-O2 -g -DNDEBUG")
-  # FIXME: Remove "x.." when CMP0054 is set to NEW
-elseif ("x${CMAKE_${_lang}_COMPILER_ID}" STREQUAL "xMSVC")
-  # FIXME: Perhaps we should be using /MD instead?
-  set(CMAKE_${_lang}_FLAGS_DEBUG_INIT "/MTd /Zi /Ob0 /Od /RTC1")
-  set(CMAKE_${_lang}_FLAGS_MINSIZEREL_INIT     "/MT /O1 /Ob1 /D NDEBUG")
-  set(CMAKE_${_lang}_FLAGS_RELEASE_INIT        "/MT /O2 /Ob2 /D NDEBUG")
-  set(CMAKE_${_lang}_FLAGS_RELWITHDEBINFO_INIT "/MT /Zi /O2 /Ob1 /D NDEBUG")
-  # Override linker flags (see Windows-MSVC.cmake for CMake's defaults)
-  # The stack size comes from the Python build system.
-  set(_msvc_stack_size "8388608")
-  set(CMAKE_EXE_LINKER_FLAGS_DEBUG_INIT "/debug /INCREMENTAL:NO /STACK:${_msvc_stack_size}")
-  set(CMAKE_EXE_LINKER_FLAGS_RELWITHDEBINFO_INIT "/debug /INCREMENTAL:NO /STACK:${_msvc_stack_size}")
-  set(CMAKE_EXE_LINKER_FLAGS_MINSIZEREL_INIT "/INCREMENTAL:NO /STACK:${_msvc_stack_size}")
-  set(CMAKE_EXE_LINKER_FLAGS_RELEASE_INIT "/INCREMENTAL:NO /STACK:${_msvc_stack_size}")
-  unset(_msvc_stack_size)
-else()
-  message(FATAL_ERROR "Overrides not set for ${_lang} compiler \"${CMAKE_${_lang}_COMPILER_ID}\"")
-endif()
-
-unset(_lang)