diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6bd77cb1fcc..436e2cec6d8 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -229,6 +229,10 @@ endif ()
 # Using system libs can cause a lot of warnings in includes (on macro expansion).
 if (UNBUNDLED OR NOT (OS_LINUX OR OS_DARWIN) OR ARCH_32)
     option (NO_WERROR "Disable -Werror compiler option" ON)
+
+    if (NOT NO_WERROR)
+        add_warning(error)
+    endif ()
 endif ()
 
 # Make this extra-checks for correct library dependencies.
diff --git a/base/CMakeLists.txt b/base/CMakeLists.txt
index 4cc9cb51670..cca578815e0 100644
--- a/base/CMakeLists.txt
+++ b/base/CMakeLists.txt
@@ -1,8 +1,3 @@
-if (NOT NO_WERROR)
-    set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror")
-    set (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Werror")
-endif ()
-
 if (USE_DEBUG_HELPERS)
     set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -include ${CMAKE_CURRENT_SOURCE_DIR}/common/iostream_debug_helpers.h")
 endif ()
diff --git a/base/common/CMakeLists.txt b/base/common/CMakeLists.txt
index 7990ef74a57..32aa25e40ea 100644
--- a/base/common/CMakeLists.txt
+++ b/base/common/CMakeLists.txt
@@ -1,13 +1,12 @@
-set (CONFIG_COMMON ${CMAKE_CURRENT_BINARY_DIR}/config_common.h)
-configure_file (${CMAKE_CURRENT_SOURCE_DIR}/config_common.h.in ${CONFIG_COMMON})
+configure_file (config_common.h.in config_common.h)
 
 add_library(apple_rt apple_rt.cpp)
-target_include_directories (apple_rt PUBLIC ${COMMON_INCLUDE_DIR})
+target_include_directories(apple_rt PRIVATE ..)  # TODO: replace with proper header-only target.
 if (DEFINED APPLE_HAVE_CLOCK_GETTIME)
     target_compile_definitions(apple_rt PUBLIC -DAPPLE_HAVE_CLOCK_GETTIME=${APPLE_HAVE_CLOCK_GETTIME})
 endif ()
 
-set (COMMON_SRCS
+set (SRCS
     argsToConfig.cpp
     coverage.cpp
     DateLUT.cpp
@@ -26,30 +25,24 @@ set (COMMON_SRCS
 )
 
 if (ENABLE_REPLXX)
-    set (COMMON_SRCS
+    set (SRCS ${SRCS}
         ReplxxLineReader.cpp
         ReplxxLineReader.h
-
-        ${COMMON_SRCS}
     )
 endif ()
 
-add_library (common
-    ${COMMON_SRCS}
-    ${CONFIG_COMMON})
+add_library (common ${SRCS})
+
+target_include_directories(common PUBLIC .. ${CMAKE_CURRENT_BINARY_DIR}/..)
 
 if (USE_INTERNAL_MEMCPY)
     set (MEMCPY_LIBRARIES memcpy)
 endif ()
 
-find_package (Threads)
-
 if(CCTZ_INCLUDE_DIR)
     target_include_directories(common BEFORE PRIVATE ${CCTZ_INCLUDE_DIR})
 endif()
 
-target_include_directories (common PUBLIC ${COMMON_INCLUDE_DIR})
-
 if (NOT USE_INTERNAL_BOOST_LIBRARY)
     target_include_directories (common SYSTEM BEFORE PUBLIC ${Boost_INCLUDE_DIRS})
 endif ()
@@ -62,19 +55,17 @@ if(CCTZ_LIBRARY)
     target_link_libraries(common PRIVATE ${CCTZ_LIBRARY})
 endif()
 
-if (ENABLE_REPLXX)
-    target_link_libraries(common PUBLIC replxx)
-endif ()
+target_link_libraries(common PUBLIC replxx)
 
 target_link_libraries (common
-        PUBLIC
-    ${Poco_Util_LIBRARY}
-    ${Poco_Foundation_LIBRARY}
-    ${CITYHASH_LIBRARIES}
-        PUBLIC
-    ${Boost_SYSTEM_LIBRARY}
-        PRIVATE
-    ${MEMCPY_LIBRARIES})
+    PUBLIC
+        ${Poco_Util_LIBRARY}
+        ${Poco_Foundation_LIBRARY}
+        ${CITYHASH_LIBRARIES}
+        ${Boost_SYSTEM_LIBRARY}
+    PRIVATE
+        ${MEMCPY_LIBRARIES}
+)
 
 if (RT_LIBRARY)
     target_link_libraries (common PRIVATE ${RT_LIBRARY})
diff --git a/cmake/add_warning.cmake b/cmake/add_warning.cmake
index 9bf2b1b5e93..3a776c98ab6 100644
--- a/cmake/add_warning.cmake
+++ b/cmake/add_warning.cmake
@@ -1,15 +1,26 @@
 include (CheckCXXCompilerFlag)
+include (CheckCCompilerFlag)
 
 # Try to add -Wflag if compiler supports it
 macro (add_warning flag)
     string (REPLACE "-" "_" underscored_flag ${flag})
     string (REPLACE "+" "x" underscored_flag ${underscored_flag})
-    check_cxx_compiler_flag("-W${flag}" SUPPORTS_FLAG_${underscored_flag})
-    if (SUPPORTS_FLAG_${underscored_flag})
+
+    check_cxx_compiler_flag("-W${flag}" SUPPORTS_CXXFLAG_${underscored_flag})
+    check_c_compiler_flag("-W${flag}" SUPPORTS_CFLAG_${underscored_flag})
+
+    if (SUPPORTS_CXXFLAG_${underscored_flag})
         set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -W${flag}")
     else ()
         message (WARNING "Flag -W${flag} is unsupported")
     endif ()
+
+    if (SUPPORTS_CFLAG_${underscored_flag})
+        set (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -W${flag}")
+    else ()
+        message (WARNING "Flag -W${flag} is unsupported")
+    endif ()
+
 endmacro ()
 
 # Try to add -Wno flag if compiler supports it
diff --git a/cmake/lib_name.cmake b/cmake/lib_name.cmake
index a793e8a1163..51a424cb4e2 100644
--- a/cmake/lib_name.cmake
+++ b/cmake/lib_name.cmake
@@ -1,5 +1,4 @@
 set(DIVIDE_INCLUDE_DIR ${ClickHouse_SOURCE_DIR}/contrib/libdivide)
-set(COMMON_INCLUDE_DIR ${ClickHouse_SOURCE_DIR}/base ${ClickHouse_BINARY_DIR}/base)
 set(DBMS_INCLUDE_DIR ${ClickHouse_SOURCE_DIR}/dbms/src ${ClickHouse_BINARY_DIR}/dbms/src)
 set(DOUBLE_CONVERSION_CONTRIB_INCLUDE_DIR ${ClickHouse_SOURCE_DIR}/contrib/double-conversion)
 set(METROHASH_CONTRIB_INCLUDE_DIR ${ClickHouse_SOURCE_DIR}/contrib/libmetrohash/src)
diff --git a/dbms/CMakeLists.txt b/dbms/CMakeLists.txt
index eeda7aa6a1f..30c5f5fddb4 100644
--- a/dbms/CMakeLists.txt
+++ b/dbms/CMakeLists.txt
@@ -36,11 +36,6 @@ if (NOT MSVC)
     set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wextra")
 endif ()
 
-if (NOT NO_WERROR)
-    set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror")
-    set (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Werror")
-endif ()
-
 # Add some warnings that are not available even with -Wall -Wextra -Wpedantic.
 
 option (WEVERYTHING "Enables -Weverything option with some exceptions. This is intended for exploration of new compiler warnings that may be found to be useful. Only makes sense for clang." ON)
@@ -577,9 +572,6 @@ target_include_directories (clickhouse_common_io PUBLIC ${DBMS_INCLUDE_DIR})
 
 target_include_directories (clickhouse_common_io SYSTEM BEFORE PUBLIC ${DOUBLE_CONVERSION_INCLUDE_DIR})
 
-# also for copy_headers.sh:
-target_include_directories (clickhouse_common_io BEFORE PRIVATE ${COMMON_INCLUDE_DIR})
-
 add_subdirectory (programs)
 add_subdirectory (tests)
 
diff --git a/dbms/programs/CMakeLists.txt b/dbms/programs/CMakeLists.txt
index 48fb30a8058..eea7a5f4fbe 100644
--- a/dbms/programs/CMakeLists.txt
+++ b/dbms/programs/CMakeLists.txt
@@ -112,7 +112,6 @@ if (CLICKHOUSE_SPLIT_BINARY)
 else ()
     add_executable (clickhouse main.cpp)
     target_link_libraries (clickhouse PRIVATE clickhouse_common_io string_utils)
-    target_include_directories (clickhouse BEFORE PRIVATE ${COMMON_INCLUDE_DIR})
     target_include_directories (clickhouse PRIVATE ${CMAKE_CURRENT_BINARY_DIR})
 
     if (ENABLE_CLICKHOUSE_SERVER)
diff --git a/dbms/src/AggregateFunctions/CMakeLists.txt b/dbms/src/AggregateFunctions/CMakeLists.txt
index dbbccc3bc7a..f0abc99811e 100644
--- a/dbms/src/AggregateFunctions/CMakeLists.txt
+++ b/dbms/src/AggregateFunctions/CMakeLists.txt
@@ -21,7 +21,6 @@ list(REMOVE_ITEM clickhouse_aggregate_functions_headers
 
 add_library(clickhouse_aggregate_functions ${clickhouse_aggregate_functions_sources})
 target_link_libraries(clickhouse_aggregate_functions PRIVATE dbms PUBLIC ${CITYHASH_LIBRARIES})
-target_include_directories(clickhouse_aggregate_functions PRIVATE ${COMMON_INCLUDE_DIR})
 
 if(ENABLE_TESTS)
     add_subdirectory(tests)
diff --git a/utils/CMakeLists.txt b/utils/CMakeLists.txt
index fcf56e82b52..44ff7d6e828 100644
--- a/utils/CMakeLists.txt
+++ b/utils/CMakeLists.txt
@@ -1,8 +1,3 @@
-if (NOT NO_WERROR)
-    set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror")
-    set (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Werror")
-endif ()
-
 if(MAKE_STATIC_LIBRARIES)
     set(MAX_LINKER_MEMORY 3500)
 else()