diff -aur ./boost_1_85_0/boost/config/stdlib/libstdcpp3.hpp ../build/extbld/third_party/boost/libs/boost_1_85_0/boost/config/stdlib/libstdcpp3.hpp
--- ./boost_1_85_0/boost/config/stdlib/libstdcpp3.hpp	2024-04-11 21:48:00.000000000 +0300
+++ ../build/extbld/third_party/boost/libs/boost_1_85_0/boost/config/stdlib/libstdcpp3.hpp	2024-07-04 19:05:00.802145810 +0300
@@ -37,7 +37,8 @@
         || defined(_GLIBCXX_HAS_GTHREADS) \
         || defined(_WIN32) \
         || defined(_AIX) \
-        || defined(__HAIKU__)
+        || defined(__HAIKU__) \
+        || defined(__EMBOX__)        
       //
       // If the std lib has thread support turned on, then turn it on in Boost
       // as well.  We do this because some gcc-3.4 std lib headers define _REENTANT
diff -aur ./boost_1_85_0/tools/build/src/tools/gcc.jam ../build/extbld/third_party/boost/libs/boost_1_85_0/tools/build/src/tools/gcc.jam
--- ./boost_1_85_0/tools/build/src/tools/gcc.jam	2024-04-11 21:48:06.000000000 +0300
+++ ../build/extbld/third_party/boost/libs/boost_1_85_0/tools/build/src/tools/gcc.jam	2024-07-05 02:57:19.031652525 +0300
@@ -395,7 +395,7 @@
 
     # iOS doesn't need pthread flag according to the https://developer.apple.com/library/archive/documentation/System/Conceptual/ManPages_iPhoneOS/man3/pthread.3.html
     # The default system libraries include pthread functions.  No additional libraries or CFLAGS are necessary to use this API.
-    local no-threading = android beos haiku sgi darwin vxworks iphone appletv ;
+    local no-threading = android beos haiku sgi darwin vxworks iphone appletv unix ;
     local threading-generic-os = [ set.difference $(all-os) : $(no-threading) $(bsd) windows cygwin solaris qnx ] ;
     threading-flags <target-os>$(threading-generic-os) : -pthread : rt ;
 }
