From 49ce46e7fdfc20a18e59c981c7f5d90cedd3cbb2 Mon Sep 17 00:00:00 2001
From: Rene Rivera <grafikrobot@gmail.com>
Date: Mon, 7 Aug 2006 05:27:15 +0000
Subject: [PATCH] Undo addition of generator.can-build. Use generator.run to
 get the same effect.

[SVN r34834]
---
 src/build/generators.jam | 28 ++++++++++------------------
 src/build/targets.jam    |  3 ++-
 src/tools/gcc.jam        | 12 +++++++-----
 3 files changed, 19 insertions(+), 24 deletions(-)

diff --git a/src/build/generators.jam b/src/build/generators.jam
index b46a91c67..b538d210b 100644
--- a/src/build/generators.jam
+++ b/src/build/generators.jam
@@ -222,13 +222,6 @@ class generator
         }
     }
     
-    # Indicates if this generator can handle building the given target
-    # combination.
-    rule can-build ( target-type : property-set : sources * )
-    {
-        return true ;
-    }
-        
     # Returns another generator which differers from $(self) in
     # - id
     # - value to <toolset> feature in properties
@@ -273,6 +266,8 @@ class generator
     
     # Tries to invoke this generator on the given sources. Returns a
     # list of generated targets (instances of 'virtual-target').
+    # Returning nothing from run indicates that the generator was
+    # unable to create the target.
     rule run ( project  # Project for which the targets are generated
                name ?   # Determines the name of 'name' attribute for 
                         # all generated targets. See 'generated-targets' method.
@@ -937,7 +932,7 @@ local rule ensure-type ( targets * )
 #
 # Note: this algorithm explicitly ignores generators for base classes if there's
 # at least one generator for requested target-type.
-local rule find-viable-generators-aux ( target-type : property-set : sources * )
+local rule find-viable-generators-aux ( target-type : property-set )
 {
     # Select generators that can create the required target type.
     local viable-generators = ;
@@ -991,27 +986,24 @@ local rule find-viable-generators-aux ( target-type : property-set : sources * )
     {
         generators.dout [ indent ] "trying generator" [ $(g).id ] "(" [ $(g).source-types ] -> [ $(g).target-types ] ")" ;
         
-        if [ $(g).can-build $(target-type) : $(property-set) : $(sources) ]
+        local m = [ $(g).match-rank $(property-set) ] ;
+        if $(m)
         {
-            local m = [ $(g).match-rank $(property-set) ] ;
-            if $(m)
-            {
-                generators.dout [ indent ] "  is viable" ;
-                viable-generators += $(g) ;
-            }
+            generators.dout [ indent ] "  is viable" ;
+            viable-generators += $(g) ;
         }
     }
                             
     return $(viable-generators) ;
 }
 
-rule find-viable-generators ( target-type : property-set : sources * )
+rule find-viable-generators ( target-type : property-set )
 {
     local key = $(target-type).$(property-set) ;
     local l = $(.fv.$(key)) ;
     if ! $(l)
     {
-        l = [ find-viable-generators-aux $(target-type) : $(property-set) : $(sources) ] ;
+        l = [ find-viable-generators-aux $(target-type) : $(property-set) ] ;
         if ! $(l)
         {
             l = none ;
@@ -1071,7 +1063,7 @@ rule find-viable-generators ( target-type : property-set : sources * )
 local rule construct-really (
    project name ? : target-type : property-set : sources * )
 {
-    viable-generators = [ find-viable-generators $(target-type) : $(property-set) : $(sources) ] ;
+    viable-generators = [ find-viable-generators $(target-type) : $(property-set) ] ;
                         
     generators.dout [ indent ] "*** " [ sequence.length $(viable-generators) ] 
       " viable generators" ;
diff --git a/src/build/targets.jam b/src/build/targets.jam
index b898f815b..c23c87fcc 100644
--- a/src/build/targets.jam
+++ b/src/build/targets.jam
@@ -1350,7 +1350,7 @@ class typed-target : basic-target
             
             # Are there any top-level generators for this type/property set.
             if ! [ generators.find-viable-generators 
-                $(self.type) : $(property-set) : $(source-targets) ]
+                $(self.type) : $(property-set) ]
             {
                 ECHO "error: no generators were found for type '$(self.type)'" ;
                 ECHO "error: and the requested properties" ;
@@ -1358,6 +1358,7 @@ class typed-target : basic-target
                 ECHO "See http://boost.org/boost-build2/doc/html/bbv2/advanced/configuration.html" ;
                 
                 ECHO "To debug this problem, try the --debug-generators option." ;
+                EXIT ;
             }
         }
         
diff --git a/src/tools/gcc.jam b/src/tools/gcc.jam
index 393b7978d..0c5d4edda 100644
--- a/src/tools/gcc.jam
+++ b/src/tools/gcc.jam
@@ -254,8 +254,9 @@ actions compile.asm
 # since it's not supported by gcc/libc.
 class gcc-linking-generator : unix-linking-generator
 {
-    rule can-build ( target-type : property-set : sources * )
+    rule run ( project name ? : property-set : sources + )
     {
+        #~ TODO: Replace this with the use of a target-os property.
         local no-static-link = ;
         if [ modules.peek : UNIX ]
         {
@@ -274,7 +275,7 @@ class gcc-linking-generator : unix-linking-generator
                 reason =
                     "On gcc, DLL can't be build with '<runtime-link>static'." ;
             }
-            else if [ type.is-derived $(target-type) EXE ]
+            else if [ type.is-derived $(self.target-types[1]) EXE ]
             {
                 for local s in $(sources)
                 {
@@ -290,16 +291,17 @@ class gcc-linking-generator : unix-linking-generator
         }
         if $(reason)
         {
-            ECHO warn:
+            ECHO warning:
                 $(reason) ;
-            ECHO warn:
+            ECHO warning:
                 "It's suggested to use '<runtime-link>static' together"
                 "with the '<link>static'." ;
             return ;
         }
         else
         {
-            return true ;
+            return [ unix-linking-generator.run $(project) $(name)
+                : $(property-set) : $(sources) ] ;
         }
     }
 }