Ticket #13641: 007-fix-build-dir-argument-on-windows.diff

tools/build/src/build-system.jam

@@ -676 +676 @@
         $(first-project-root-location) ] ;
     local first-project-root = [ project.target $(first-project-root-module) ] ;
     local first-build-build-dir = [ $(first-project-root).build-dir ] ;
+
+    # Workaround for https://svn.boost.org/trac10/ticket/13641
+    local first-build-build-dir-workaround = [ MATCH ^/(.*)$ : $(first-build-build-dir) ] ;
+
+    if [ os.name ] = NT && $(first-build-build-dir-workaround)
+    {
+        configure.set-log-file $(first-build-build-dir-workaround)/config.log ;
+    }
+    else
+    {
     configure.set-log-file $(first-build-build-dir)/config.log ;
+    }
+
     config-cache.load $(first-build-build-dir)/project-cache.jam ;
 
     # Expand properties specified on the command line into multiple property