diff --git a/cc/config/clang.go b/cc/config/clang.go
index 64bb96e..6f08fa9 100644
--- a/cc/config/clang.go
+++ b/cc/config/clang.go
@@ -97,6 +97,12 @@
 		// http://b/29823425 Disable -Wexpansion-to-defined for Clang update to r271374
 		"-Wno-expansion-to-defined",
 
+		// http://b/68236239 Allow 0/NULL instead of using nullptr everywhere.
+		"-Wno-zero-as-null-pointer-constant",
+
+		// http://b/68236396 Allow unknown warning options.
+		"-Wno-unknown-warning-option",
+
 		// http://b/36463318 Clang executes with an absolute path, so clang-provided
 		// headers are now absolute.
 		"-fdebug-prefix-map=$$PWD/=",