Make possible to use clang on Windows (clang-cl)

-DWITH_ASAN can be used as well now, on x64

Fix many clang-cl warnings.

2 files changed, 50 insertions, 4 deletions

diff --git a/cmake/maintainer.cmake b/cmake/maintainer.cmake
index 6993bae3975..4a13edceece 100644
--- a/cmake/maintainer.cmake
+++ b/cmake/maintainer.cmake
@@ -13,6 +13,10 @@
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA
 
+IF(MSVC)
+  RETURN()
+ENDIF()
+
 # Common warning flags for GCC, G++, Clang and Clang++
 SET(MY_WARNING_FLAGS
   -Wall
diff --git a/cmake/os/Windows.cmake b/cmake/os/Windows.cmake
index aa948a7f5b2..3935894781e 100644
--- a/cmake/os/Windows.cmake
+++ b/cmake/os/Windows.cmake
@@ -59,7 +59,41 @@ IF(MINGW AND CMAKE_SIZEOF_VOID_P EQUAL 4)
   ADD_DEFINITIONS(-march=i486)
 ENDIF()
 
+FUNCTION(ENABLE_ASAN)
+  IF(NOT (MSVC AND CMAKE_CXX_COMPILER_ID MATCHES Clang))
+    MESSAGE(FATAL_ERROR "clang-cl is necessary to enable asan")
+  ENDIF()
+  # currently, asan is broken with static CRT.
+  IF(NOT(MSVC_CRT_TYPE STREQUAL "/MD"))
+    MESSAGE(FATAL_ERROR "-DWITH_ASAN cmake parameter also requires -DMSVC_CRT_TYPE=/MD")
+  ENDIF()
+  IF(CMAKE_SIZEOF_VOID_P EQUAL 4)
+    MESSAGE(FATAL_ERROR "-DWITH_ASAN on Windows requires 64bit build")
+  ENDIF()
+  # After installation, clang lib directory should be added to PATH
+  # (e.g C:/Program Files/LLVM/lib/clang/5.0.1/lib/windows)
+  FIND_LIBRARY(CLANG_RT_ASAN_DYNAMIC clang_rt.asan_dynamic-x86_64.lib)
+  IF(NOT CLANG_RT_ASAN_DYNAMIC)
+    MESSAGE(FATAL_ERROR "Can't enable ASAN : missing clang_rt.asan_dynamic-x86_64.lib")
+  ENDIF()
+
+  FIND_LIBRARY(CLANG_RT_ASAN_DYNAMIC_THUNK clang_rt.asan_dynamic_runtime_thunk-x86_64.lib)
+  IF(NOT CLANG_RT_ASAN_DYNAMIC_THUNK)
+     MESSAGE(FATAL_ERROR "Can't enable ASAN : missing clang_rt.asan_dynamic_runtime_thunk-x86_64.lib")
+  ENDIF()
+
+  STRING(APPEND CMAKE_C_FLAGS " -fsanitize=address")
+  STRING(APPEND CMAKE_CXX_FLAGS " -fsanitize=address")
+
+  LINK_LIBRARIES(${CLANG_RT_ASAN_DYNAMIC} ${CLANG_RT_ASAN_DYNAMIC_THUNK})
+ENDFUNCTION()
+
+
 IF(MSVC)
+  IF(WITH_ASAN)
+    ENABLE_ASAN()
+  ENDIF()
+
   # Disable mingw based pkg-config found in Strawberry perl
   SET(PKG_CONFIG_EXECUTABLE 0 CACHE INTERNAL "")
   SET(MSVC_CRT_TYPE /MT CACHE STRING
@@ -119,8 +153,16 @@ IF(MSVC)
     STRING(APPEND ${flag} " /Z7")
    ENDIF()
   ENDFOREACH()
-  
- 
+
+  IF(CMAKE_CXX_COMPILER_ID MATCHES Clang)
+     SET(CLANG_CL_FLAGS
+"-Wno-unused-parameter -Wno-unused-command-line-argument -Wno-pointer-sign -Wno-deprecated-register \
+-Wno-missing-braces -Wno-unused-function -msse4.2 "
+    )
+    SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${CLANG_CL_FLAGS}")
+    SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${CLANG_CL_FLAGS}")
+  ENDIF()
+
   # Fix CMake's predefined huge stack size
   FOREACH(type EXE SHARED MODULE)
    STRING(REGEX REPLACE "/STACK:([^ ]+)" "" CMAKE_${type}_LINKER_FLAGS "${CMAKE_${type}_LINKER_FLAGS}")
@@ -139,7 +181,7 @@ IF(MSVC)
   ENDIF()
   
   # Speed up multiprocessor build
-  IF (MSVC_VERSION GREATER 1400)
+  IF (MSVC_VERSION GREATER 1400 AND (NOT CMAKE_CXX_COMPILER_ID MATCHES Clang))
     SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} /MP")
     SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /MP")
   ENDIF()
@@ -147,7 +189,7 @@ IF(MSVC)
   #TODO: update the code and remove the disabled warnings
   SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} /we4700 /we4311 /we4477 /we4302 /we4090")
   SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /we4099 /we4700 /we4311 /we4477 /we4302 /we4090")
-  IF(MSVC_VERSION GREATER 1910)
+  IF(MSVC_VERSION GREATER 1910  AND (NOT CMAKE_CXX_COMPILER_ID MATCHES Clang))
     SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /permissive-")
   ENDIF()
   ADD_DEFINITIONS(-D_CRT_NONSTDC_NO_WARNINGS)