Corrects a problem in the handling of <conditional>@rule in

the lib rule, e.g.:

lib foo : : <conditional>@sources ;

Prior to the patch, this was treating the library as a prebuilt
library because of the absence of any source arguments.  Thus
nothing would get built.

 * tools/builtin.jam
   (lib-generator.run): Added additional constraint when setting
   library type to SEARCHED_LIB.

Patch from Mark Evans.


[SVN r32880]

v2/tools/builtin.jam

@@ -404,7 +404,10 @@ class lib-generator : generator
             local properties = [ $(property-set).raw ] ;
             # Determine the needed target type
             local actual-type ;
-            if <search> in $(properties:G) || <name> in $(properties:G)
+	        # <source>files can be generated by <conditional>@rule feature
+	        # in which case we don't consider it a SEARCHED_LIB type.
+            if ! <source> in $(properties:G) &&
+               ( <search> in $(properties:G) || <name> in $(properties:G) )
             {
                 actual-type = SEARCHED_LIB ;
             }