missing boost/config.hpp includes

[urnathan]

Some of the exception headers examine boost control macros without first including config.hpp. Thus, they are not self-contained, and that creates difficulty building them as clang modules or c++ header units (specifically they think the macros are undefined, which might mismatch the rest of the build, leading to conflicts). Here are the ones I found problematic (I think there are others, particularly WRT BOOST_EXCEPTION_ENABLE_WARNINGS, but that doesn't bite in this case.

diff --git a/third-party/tp2/boost/1.77.0/boost_1_77_0/boost/exception/current_exception_cast.hpp b/third-party/tp2/boost/1.77.0/boost_1_77_0/boost/exception/current_exception_cast.hpp
--- a/third-party/tp2/boost/1.77.0/boost_1_77_0/boost/exception/current_exception_cast.hpp
+++ b/third-party/tp2/boost/1.77.0/boost_1_77_0/boost/exception/current_exception_cast.hpp
@@ -6,6 +6,8 @@
 #ifndef BOOST_EXCEPTION_7E83C166200811DE885E826156D89593
 #define BOOST_EXCEPTION_7E83C166200811DE885E826156D89593

+#include <boost/config.hpp>
+
 #ifndef BOOST_EXCEPTION_ENABLE_WARNINGS
 #if __GNUC__*100+__GNUC_MINOR__>301
 #pragma GCC system_header
diff --git a/third-party/tp2/boost/1.77.0/boost_1_77_0/boost/exception/detail/is_output_streamable.hpp b/third-party/tp2/boost/1.77.0/boost_1_77_0/boost/exception/detail/is_output_streamable.hpp
--- a/third-party/tp2/boost/1.77.0/boost_1_77_0/boost/exception/detail/is_output_streamable.hpp
+++ b/third-party/tp2/boost/1.77.0/boost_1_77_0/boost/exception/detail/is_output_streamable.hpp
@@ -6,6 +6,7 @@
 #ifndef BOOST_EXCEPTION_898984B4076411DD973EDFA055D89593
 #define BOOST_EXCEPTION_898984B4076411DD973EDFA055D89593

+#include <boost/config.hpp>
 #include <ostream>

 #ifndef BOOST_EXCEPTION_ENABLE_WARNINGS
diff --git a/third-party/tp2/boost/1.77.0/boost_1_77_0/boost/exception/detail/shared_ptr.hpp b/third-party/tp2/boost/1.77.0/boost_1_77_0/boost/exception/detail/shared_ptr.hpp
--- a/third-party/tp2/boost/1.77.0/boost_1_77_0/boost/exception/detail/shared_ptr.hpp
+++ b/third-party/tp2/boost/1.77.0/boost_1_77_0/boost/exception/detail/shared_ptr.hpp
@@ -6,6 +6,8 @@
 #ifndef BOOST_EXCEPTION_837060E885AF11E68DA91D15E31AC075
 #define BOOST_EXCEPTION_837060E885AF11E68DA91D15E31AC075

+#include <boost/config.hpp>
+
 #ifdef BOOST_EXCEPTION_MINI_BOOST
 #include  <memory>
 namespace boost { namespace exception_detail { using std::shared_ptr; } }

[zajo]

I see that clone_current_exception.hpp uses BOOST_NO_EXCEPTIONS without #include <boost/config.hpp>, which is a bug, but I think there aren't any others. I'll fix this one, but if there is another case where such macro is used without the include, please let me know.