Fixes compilation on Power8

This fixes #3000

Closes #3002.

PiperOrigin-RevId: 156046356
diff --git a/tools/cpp/CROSSTOOL b/tools/cpp/CROSSTOOL
index bb22006..d70a6dc 100644
--- a/tools/cpp/CROSSTOOL
+++ b/tools/cpp/CROSSTOOL
@@ -45,6 +45,11 @@
 }
 
 default_toolchain {
+  cpu: "ppc64"
+  toolchain_identifier: "local_linux"
+}
+
+default_toolchain {
   cpu: "ios_x86_64"
   toolchain_identifier: "ios_x86_64"
 }