Modified: trunk/dports/lang/libcxx/Portfile (130423 => 130424)

--- trunk/dports/lang/libcxx/Portfile	2014-12-30 06:50:58 UTC (rev 130423)
+++ trunk/dports/lang/libcxx/Portfile	2014-12-30 06:53:56 UTC (rev 130424)
@@ -30,19 +30,24 @@
 
 set root_path ${prefix}/var/host/${name}-${version}-${revision}
 
-if {${os.major} >= 11} {
-    fetch {}
-    build {}
-    destroot {
-        xinstall -d ${destroot}${prefix}/share/doc/${name}
-        system "echo ${name} is an empty port on this OS version because the functionality is already provided by the OS. > ${destroot}${prefix}/share/doc/${name}/README.txt"
+platform darwin {
+    if {${os.major} < 10} {
+        pre-fetch {
+            ui_error "${name} is not supported on Leopard or earlier."
+            error "unsupported platform"
+        }
     }
-} elseif {${os.major} < 10} {
-    pre-fetch {
-        ui_error "${name} is not supported on Leopard or earlier."
-        error "unsupported platform"
+
+    if {${os.major} < 11} {
+        post-activate {
+            system "ditto ${root_path} /"
+        }
     }
-} else {
+}
+
+variant replacemnt_libcxx description {EXPERTS ONLY: Build a replacement libcxxabi and libcxx even if it is already part of the base OS.} {}
+
+if {${os.major} < 11 || [variant_isset replacemnt_libcxx]} {
     # 3.5 and 3.6 are blacklisted to prevent dependency cycles
     compiler.blacklist *gcc* {clang < 100} macports-clang-3.5 macports-clang-3.6
 
@@ -61,18 +66,24 @@
 
     # We want to use the host's libc++ everywhere because we want to ensure
     # that only *ONE* copy of this library is in any process's address space.
-    # On newer OS versions (Lion+), this port does not install anything.  On
-    # Snow Leopard, this port provides this library in /usr for binary
+    # On Snow Leopard, this port provides this library in /usr for binary
     # compatibility with Lion and later.
+    #
+    # On newer OS version, this port does not install the content to /usr and
+    # just leaves it to expert users who may want to replace their system
+    # runtime.
 
     destroot {
         xinstall -m 755 -d ${destroot}${root_path}/usr/lib
         xinstall -m 755 ${worksrcpath}/lib/libc++.1.dylib ${destroot}${root_path}/usr/lib
         ln -s libc++.1.dylib ${destroot}${root_path}/usr/lib/libc++.dylib
     }
-
-    post-activate {
-        system "ditto ${root_path} /"
+} else {
+    fetch {}
+    build {}
+    destroot {
+        xinstall -d ${destroot}${prefix}/share/doc/${name}
+        system "echo ${name} is an empty port on this OS version because the functionality is already provided by the OS. > ${destroot}${prefix}/share/doc/${name}/README.txt"
     }
 }