libcxx: fix build error.

Signed-off-by: zhanghongyu <zhanghongyu@xiaomi.com>

arch/sim/src/cmake/Toolchain.cmake

@@ -94,6 +94,10 @@ else()
   endif()
 endif()
 
+if(CONFIG_CXX_STANDARD)
+  add_compile_options($<$<COMPILE_LANGUAGE:CXX>:-std=${CONFIG_CXX_STANDARD}>)
+endif()
+
 set(ARCHCFLAGS "-Wstrict-prototypes")
 set(ARCHCXXFLAGS "-nostdinc++")
 

libs/libxx/0001_fix_stdatomic_h_miss_typedef.patch

@@ -0,0 +1,11 @@
+--- libcxx/include/stdatomic.h.old	2023-12-06 21:01:46.168049453 +0800
++++ libcxx/include/stdatomic.h	2023-12-06 21:01:55.056057032 +0800
+@@ -220,7 +220,7 @@
+ using std::atomic_signal_fence _LIBCPP_USING_IF_EXISTS;
+ using std::atomic_thread_fence _LIBCPP_USING_IF_EXISTS;
+ 
+-#elif defined(_LIBCPP_COMPILER_CLANG_BASED)
++#else
+ 
+ // Before C++23, we include the next <stdatomic.h> on the path to avoid hijacking
+ // the header. We do this because Clang has historically shipped a <stdatomic.h>

libs/libxx/libcxx.cmake

@@ -24,22 +24,7 @@ if(NOT EXISTS ${CMAKE_CURRENT_LIST_DIR}/libcxx)
 
   # cmake-format: off
   set(LIBCXX_PATCH_COMMAND
-      patch -p0 -d ${CMAKE_CURRENT_LIST_DIR} <
+  patch -p1 -d ${CMAKE_CURRENT_LIST_DIR}/libcxx < ${CMAKE_CURRENT_LIST_DIR}/0001_fix_stdatomic_h_miss_typedef.patch)
-      ${CMAKE_CURRENT_LIST_DIR}/0001-Remove-the-locale-fallback-for-NuttX.patch
-      && patch -p0 -d ${CMAKE_CURRENT_LIST_DIR} <
-      ${CMAKE_CURRENT_LIST_DIR}/0001-libc-avoid-the-waring-__EXCEPTIONS-is-not-defined-ev.patch
-      && patch -p1 -d ${CMAKE_CURRENT_LIST_DIR} <
-      ${CMAKE_CURRENT_LIST_DIR}/0001-libcxx-Rename-PS-macro-to-avoid-clashing-with-Xtensa.patch
-  )
-
-  if(CONFIG_LIBC_ARCH_ATOMIC)
-    list(
-      APPEND
-      LIBCXX_PATCH_COMMAND
-      && patch -p1 -d ${CMAKE_CURRENT_LIST_DIR} <
-      ${CMAKE_CURRENT_LIST_DIR}/0002-Omit-atomic_-un-signed_lock_free-if-unsupported.patch
-    )
-  endif()
   # cmake-format: on
   FetchContent_Declare(
     libcxx
@@ -68,13 +53,31 @@ if(NOT EXISTS ${CMAKE_CURRENT_LIST_DIR}/libcxx)
     FetchContent_Populate(libcxx)
   endif()
 
+  execute_process(
+    COMMAND
+      sh -c
+      "ln -s ${CMAKE_CURRENT_LIST_DIR}/libcxx/include ${NUTTX_DIR}/include/libcxx"
+    WORKING_DIRECTORY ${CMAKE_CURRENT_LIST_DIR})
+  execute_process(
+    COMMAND
+      sh -c
+      "cp ${CMAKE_CURRENT_LIST_DIR}/__config_site ${NUTTX_DIR}/include/libcxx/__config_site"
+    WORKING_DIRECTORY ${CMAKE_CURRENT_LIST_DIR})
 endif()
 
+find_program(GN_EXECUTABLEXX gn REQUIRED)
+message("GN_EXECUTABLEXX ${GN_EXECUTABLEXX}")
+
 set_property(
   TARGET nuttx
   APPEND
   PROPERTY NUTTX_INCLUDE_DIRECTORIES ${CMAKE_CURRENT_LIST_DIR}/libcxx/include)
 
+set_property(
+  TARGET nuttx
+  APPEND
+  PROPERTY NUTTX_INCLUDE_DIRECTORIES ${CMAKE_CURRENT_LIST_DIR}/libcxx/src)
+
 add_compile_definitions(_LIBCPP_BUILDING_LIBRARY)
 if(CONFIG_LIBSUPCXX)
   add_compile_definitions(__GLIBCXX__)