From c6a5df5a4e1eb13f80ddbcf426531380b8e4fcaf Mon Sep 17 00:00:00 2001
From: jehelset <47066444+jehelset@users.noreply.github.com>
Date: Sun, 9 Feb 2020 15:45:45 +0100
Subject: [PATCH] move abstract-file-target.root to virtual-target. (#537)

seems to only be called from basic-target.create-subvariant, which
seems (looking at the comments and 5.6.4 of docs) to assume that it
exists on virtual-target.

without this fix a user wanting to produce something derived from
virtual-target in the construct-function of something derived from
basic-target will get an error.
---
 src/build/virtual-target.jam | 25 +++++++++++++------------
 1 file changed, 13 insertions(+), 12 deletions(-)

diff --git a/src/build/virtual-target.jam b/src/build/virtual-target.jam
index 5df6bbe7e..d7b84321c 100644
--- a/src/build/virtual-target.jam
+++ b/src/build/virtual-target.jam
@@ -174,6 +174,19 @@ class virtual-target
 
 # private: (overridables)
 
+    # Sets/gets the 'root' flag. Target is root if it directly corresponds to
+    # some variant of a main target.
+    #
+    rule root ( set ? )
+    {
+        if $(set)
+        {
+            self.root = true ;
+        }
+        return $(self.root) ;
+    }
+
+
     # Sets up build actions for 'target'. Should call appropriate rules and set
     # target variables.
     #
@@ -296,18 +309,6 @@ class abstract-file-target : virtual-target
         return $(self.action) ;
     }
 
-    # Sets/gets the 'root' flag. Target is root if it directly corresponds to
-    # some variant of a main target.
-    #
-    rule root ( set ? )
-    {
-        if $(set)
-        {
-            self.root = true ;
-        }
-        return $(self.root) ;
-    }
-
     # Gets or sets the subvariant which created this target. Subvariant is set
     # when target is brought into existence and is never changed after that. In
     # particular, if a target is shared by multiple subvariants, only the first