https://github.com/boostorg/context/commit/d039c8e4da79dbc76481236249e22892bfdde047
https://bugs.gentoo.org/904132

From d039c8e4da79dbc76481236249e22892bfdde047 Mon Sep 17 00:00:00 2001
From: Nikita Kniazev <nok.raven@gmail.com>
Date: Thu, 23 Mar 2023 16:23:07 +0300
Subject: [PATCH] Fix arm64 detection broken by recent B2 change

--- a/libs/context/build/Jamfile.v2
+++ b/libs/context/build/Jamfile.v2
@@ -79,7 +79,7 @@ local rule default_abi ( )
     local tmp = sysv ;
     if [ os.name ] = "NT" { tmp = ms ; }
     else if [ os.name ] = "CYGWIN" { tmp = ms ; }
-    else if [ os.platform ] = "ARM" { tmp = aapcs ; }
+    else if [ os.platform ] in ARM ARM64 { tmp = aapcs ; }
     else if [ os.platform ] = "MIPS32" { tmp = o32 ; }
     else if [ os.platform ] = "MIPS64" { tmp = n64 ; }
     return $(tmp) ;