diff --git a/Library/Homebrew/extend/os/mac/extend/ENV/super.rb b/Library/Homebrew/extend/os/mac/extend/ENV/super.rb
index eba6a54c74..82b81a20f9 100644
--- a/Library/Homebrew/extend/os/mac/extend/ENV/super.rb
+++ b/Library/Homebrew/extend/os/mac/extend/ENV/super.rb
@@ -108,7 +108,7 @@ module Superenv
   # @private
   def setup_build_environment(formula = nil)
     sdk = formula ? MacOS.sdk_for_formula(formula) : MacOS.sdk
-    if MacOS.sdk_root_needed?
+    if MacOS.sdk_root_needed? || sdk.source == :xcode
       self["HOMEBREW_SDKROOT"] = sdk.path
       self["HOMEBREW_DEVELOPER_DIR"] = if sdk.source == :xcode
         MacOS::Xcode.prefix