Index: gcc.jam
===================================================================
--- gcc.jam	(revision 44702)
+++ gcc.jam	(working copy)
@@ -72,15 +72,22 @@
 
 import rc ;
 
-# Initializes the gcc toolset for the given version. If necessary, command may
+# Initializes the gcc toolset and gives it an identity. 
+# If necessary, command may
 # be used to specify where the compiler is located. The parameter 'options' is a
 # space-delimited list of options, each one specified as
 # <option-name>option-value. Valid option names are: cxxflags, linkflags and
 # linker-type. Accepted linker-type values are gnu, darwin, osf, hpux or sun
 # and the default value will be selected based on the current OS.
 # Example:
-#   using gcc : 3.4 : : <cxxflags>foo <linkflags>bar <linker-type>sun ;
-rule init ( version ? : command * : options * )
+#   using gcc : myid : : <cxxflags>foo <linkflags>bar <linker-type>sun ;
+# this will define a subfeature value <toolset-gcc:identity>myid which allows
+# to specify the compiler by gcc-myid.
+# Please note that the values for subfeatures <toolset-gcc:version> and 
+# <toolset-gcc:flavor> are automatically probed from the compiler.
+# The version is from gcc -dumpversion, and flavor is from -dumpmachine with
+# all "-" convertet to "_".
+rule init ( identity ? : command * : options * )
 {
     # Information about the gcc command...
     #   The command.
@@ -91,6 +98,9 @@
     local bin ;
     #   The flavor of compiler.
     local flavor = [ feature.get-values <flavor> : $(options) ] ;
+    #   The version of compiler.
+    local version ;
+    identity ?= autoconfig ;
     #   Autodetect the root and bin dir if not given.
     if $(command)
     {
@@ -103,16 +113,19 @@
         # The 'command' variable can have multiple elements. When calling
         # the SHELL builtin we need a single string.
         local command-string = $(command:J=" ") ;
-        local machine = [ MATCH "^([^ ]+)"
+        local nl = "
+" ;
+        local machine = [ MATCH "^([^ $(nl)]+)"
             : [ SHELL "$(command-string) -dumpmachine" ] ] ;
-        version ?= [ MATCH "^([0-9.]+)"
+        version = [ MATCH "^([0-9.]+)"
             : [ SHELL "$(command-string) -dumpversion" ] ] ;
-        switch $(machine:L)
-        {
-            case *mingw* : flavor ?= mingw ;
-        }
+        flavor ?= [ regex.replace $(machine) "-" "_" ] ;
     }
 
+    local requirement =
+        <toolset-gcc:version>$(version)
+        <toolset-gcc:flavor>$(flavor) ;
+
     local condition ;
     if $(flavor)
     {
@@ -120,12 +133,25 @@
             : version $(version)
             : flavor $(flavor)
             ] ;
+
+        # the identity subfeature is optional and must not be part of the
+        # condition, so declare it outside of chek-init-parameters
+        if ! $(.identity-declared) {
+            feature.subfeature toolset gcc : identity : : optional ;
+            .identity-declared = true ;
+        }
+        feature.extend-subfeature toolset gcc : identity : $(identity) ;
+        
+        # the generators are also conditioned on version and flavor
+        gcc_register $(requirement) ;
+        
+        # allow shorthand specification by identity to request correct
+        # compiler.
+        toolset.add-requirements  <toolset-gcc:identity>$(identity):$(requirement) ;
     }
     else
     {
-        condition = [ common.check-init-parameters gcc
-            : version $(version)
-            ] ;
+        errors.user-error "Could not detect gcc variant." ;
     }
 
     common.handle-options gcc : $(condition) : $(command) : $(options) ;
@@ -206,9 +232,14 @@
     JAMSHELL = % ;
 }
 
-generators.register-c-compiler gcc.compile.c++ : CPP : OBJ : <toolset>gcc ;
-generators.register-c-compiler gcc.compile.c   : C   : OBJ : <toolset>gcc ;
-generators.register-c-compiler gcc.compile.asm : ASM : OBJ : <toolset>gcc ;
+rule gcc_register ( requirement * ) {
+    generators.register-c-compiler gcc.compile.c++ : CPP : OBJ 
+        : <toolset>gcc $(requirement) ;
+    generators.register-c-compiler gcc.compile.c   : C   : OBJ 
+        : <toolset>gcc $(requirement) ;
+    generators.register-c-compiler gcc.compile.asm : ASM : OBJ 
+        : <toolset>gcc $(requirement) ;
+}
 
 # pch support