diff --git a/Library/Homebrew/extend/os/mac/extend/ENV/std.rb b/Library/Homebrew/extend/os/mac/extend/ENV/std.rb
index 1bd5899bfd..ae04e62a8d 100644
--- a/Library/Homebrew/extend/os/mac/extend/ENV/std.rb
+++ b/Library/Homebrew/extend/os/mac/extend/ENV/std.rb
@@ -81,7 +81,7 @@ module Stdenv
     prepend "LDFLAGS", "-L#{HOMEBREW_PREFIX}/lib"
 
     sdk = formula ? MacOS.sdk_for_formula(formula, version) : MacOS.sdk(version)
-    return if !MacOS.sdk_root_needed? && sdk.source != :xcode
+    return if !MacOS.sdk_root_needed? && sdk&.source != :xcode
 
     sdk = sdk.path
 
diff --git a/Library/Homebrew/extend/os/mac/extend/ENV/super.rb b/Library/Homebrew/extend/os/mac/extend/ENV/super.rb
index 82b81a20f9..f1b92e5ce2 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? || sdk.source == :xcode
+    if MacOS.sdk_root_needed? || sdk&.source == :xcode
       self["HOMEBREW_SDKROOT"] = sdk.path
       self["HOMEBREW_DEVELOPER_DIR"] = if sdk.source == :xcode
         MacOS::Xcode.prefix