Build: patch Boost for incompatibility with Xcode and libc++ 15

This is fixed in newer boost versions, but stick to the existing version now
for VFX platform compatibility. This change only affects macOS libraries,
since no other platform uses libc++.

build_files/build_environment/cmake/boost.cmake

@@ -13,7 +13,7 @@ elseif(APPLE)
   set(BOOST_BUILD_COMMAND ./b2)
   set(BOOST_BUILD_OPTIONS toolset=clang-darwin cxxflags=${PLATFORM_CXXFLAGS} linkflags=${PLATFORM_LDFLAGS} visibility=global --disable-icu boost.locale.icu=off)
   set(BOOST_HARVEST_CMD echo .)
-  set(BOOST_PATCH_COMMAND echo .)
+  set(BOOST_PATCH_COMMAND ${PATCH_CMD} -p 1 -d ${BUILD_DIR}/boost/src/external_boost < ${PATCH_DIR}/boost.diff)
 else()
   set(BOOST_HARVEST_CMD echo .)
   set(BOOST_CONFIGURE_COMMAND ./bootstrap.sh)

build_files/build_environment/patches/boost.diff

@@ -0,0 +1,28 @@
+--- a/boost/python//detail/wrap_python.hpp	2022-12-09 19:16:17
++++ b/boost/python//detail/wrap_python.hpp	2022-12-09 19:18:08
+@@ -206,7 +206,8 @@
+ 
+ #ifdef DEBUG_UNDEFINED_FROM_WRAP_PYTHON_H
+ # undef DEBUG_UNDEFINED_FROM_WRAP_PYTHON_H
+-# define _DEBUG
++// BLENDER: TBB expects this to have a value.
++# define _DEBUG 1
+ # ifdef _CRT_NOFORCE_MANIFEST_DEFINED_FROM_WRAP_PYTHON_H
+ #  undef _CRT_NOFORCE_MANIFEST_DEFINED_FROM_WRAP_PYTHON_H
+ #  undef _CRT_NOFORCE_MANIFEST
+--- a/boost/config/stdlib/libcpp.hpp	2022-08-03 22:47:07.000000000 -0400
++++ b/boost/config/stdlib/libcpp.hpp	2022-09-16 22:16:17.044119011 -0400
+@@ -168,4 +168,13 @@
+ #  define BOOST_NO_CXX14_HDR_SHARED_MUTEX
+ #endif
+ 
++#if defined(_LIBCPP_VERSION) && _LIBCPP_VERSION >= 15000
++//
++// Unary function is now deprecated in C++11 and later:
++//
++#if __cplusplus >= 201103L
++#define BOOST_NO_CXX98_FUNCTION_BASE
++#endif
++#endif
++
+ //  --- end ---