do not use use_custom_libcxx=true for windows

Author: mpromonet

CMakeLists.txt

@@ -41,7 +41,8 @@ MESSAGE("PATH = $ENV{PATH}")
 find_package(Git)
 
 # webrtc build
-set (WEBRTCOBJS ${WEBRTCROOT}/src/out/${CMAKE_BUILD_TYPE}/obj)
+set (WEBRTCBUILD ${WEBRTCROOT}/src/out/${CMAKE_BUILD_TYPE})
+set (WEBRTCOBJS ${WEBRTCBUILD}/obj)
 
 if (NOT EXISTS ${WEBRTCOBJS}/${CMAKE_STATIC_LIBRARY_PREFIX}webrtc${CMAKE_STATIC_LIBRARY_SUFFIX})
   if(GIT_FOUND)
@@ -85,7 +86,7 @@ if (NOT EXISTS ${WEBRTCOBJS}/${CMAKE_STATIC_LIBRARY_PREFIX}webrtc${CMAKE_STATIC_
 
   set (WEBRTCARGS rtc_include_tests=false\nrtc_enable_protobuf=false\nrtc_build_examples=false\nrtc_build_tools=false\ntreat_warnings_as_errors=false\nenable_js_protobuf=false\nuse_glib=false\n)
   set (WEBRTCARGS libyuv_use_sme=false\n${WEBRTCARGS})
-  if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
+  if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang" AND NOT WIN32)
     set (WEBRTCARGS use_custom_libcxx=true\n${WEBRTCARGS})
   else()
     set (WEBRTCARGS use_custom_libcxx=false\n${WEBRTCARGS})
@@ -219,24 +220,26 @@ add_executable (${CMAKE_PROJECT_NAME} ${SOURCE} ${WEBRTCEXTRAOBJS})
 target_include_directories(${CMAKE_PROJECT_NAME} PRIVATE inc)
 
 # webrtc
-if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
+if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang" AND NOT WIN32)
   message(STATUS "Using Clang: enabling libc++")
 
-  if (WIN32)
-    set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -I${WEBRTCROOT}/src/buildtools/third_party/libc++ -D_LIBCPP_HARDENING_MODE=_LIBCPP_HARDENING_MODE_EXTENSIVE")
+  if (EXISTS ${WEBRTCBUILD}/gen/third_party/libc++/src/include)
+    set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -isystem${WEBRTCBUILD}/gen/third_party/libc++/src/include")
   else()
-    set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -I${WEBRTCROOT}/src/buildtools/third_party/libc++ -nostdinc++ -isystem${WEBRTCROOT}/src/third_party/libc++/src/include -isystem${WEBRTCROOT}/src/third_party/libc++abi/src/include -D_LIBCPP_HARDENING_MODE=_LIBCPP_HARDENING_MODE_EXTENSIVE")
-    find_library(LIBC++ NAMES c++ HINTS "${WEBRTCOBJS}/buildtools/third_party" NO_DEFAULT_PATH)
-    if (LIBC++)
-      message(STATUS "Found libc++ library at ${LIBC++}")
-      target_link_libraries(${CMAKE_PROJECT_NAME} "${LIBC++}")
-    endif()
-    find_library(LIBC++ABI NAMES c++abi HINTS "${WEBRTCOBJS}/buildtools/third_party" NO_DEFAULT_PATH)
-    if (LIBC++ABI)
-      message(STATUS "Found libc++abi library at ${LIBC++ABI}")
-      target_link_libraries(${CMAKE_PROJECT_NAME} "${LIBC++ABI}")
-    endif()
+    set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -isystem${WEBRTCROOT}/src/third_party/libc++/src/include")
+  endif()
+  set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -I${WEBRTCROOT}/src/buildtools/third_party/libc++ -nostdinc++ -isystem${WEBRTCROOT}/src/third_party/libc++abi/src/include -D_LIBCPP_HARDENING_MODE=_LIBCPP_HARDENING_MODE_EXTENSIVE")
+  find_library(LIBC++ NAMES c++ HINTS "${WEBRTCOBJS}/buildtools/third_party" NO_DEFAULT_PATH)
+  if (LIBC++)
+    message(STATUS "Found libc++ library at ${LIBC++}")
+    target_link_libraries(${CMAKE_PROJECT_NAME} "${LIBC++}")
+  endif()
+  find_library(LIBC++ABI NAMES c++abi HINTS "${WEBRTCOBJS}/buildtools/third_party" NO_DEFAULT_PATH)
+  if (LIBC++ABI)
+    message(STATUS "Found libc++abi library at ${LIBC++ABI}")
+    target_link_libraries(${CMAKE_PROJECT_NAME} "${LIBC++ABI}")
   endif()
+  target_compile_options(${CMAKE_PROJECT_NAME} PRIVATE -Wno-nullability-completeness)
 endif()
 
 target_include_directories(${CMAKE_PROJECT_NAME} PRIVATE ${WEBRTCROOT}/src ${WEBRTCROOT}/src/third_party/abseil-cpp ${WEBRTCROOT}/src/third_party/jsoncpp/source/include  ${WEBRTCROOT}/src/third_party/jsoncpp/generated ${WEBRTCROOT}/src/third_party/libyuv/include)