diff --git a/Library/Homebrew/build.rb b/Library/Homebrew/build.rb
index 7827a93609..de47babe8c 100644
--- a/Library/Homebrew/build.rb
+++ b/Library/Homebrew/build.rb
@@ -268,7 +268,7 @@ rescue Exception => e # rubocop:disable Lint/RescueException
     error_hash["output"] = e.output
   end
 
-  error_pipe.puts error_hash.to_json
-  error_pipe.close
+  error_pipe&.puts error_hash.to_json
+  error_pipe&.close
   exit! 1
 end
diff --git a/Library/Homebrew/formulary.rb b/Library/Homebrew/formulary.rb
index a101b4d703..1d30222bd5 100644
--- a/Library/Homebrew/formulary.rb
+++ b/Library/Homebrew/formulary.rb
@@ -622,7 +622,7 @@ module Formulary
         if !path_realpath.start_with?("#{HOMEBREW_CELLAR}/", "#{HOMEBREW_LIBRARY}/Taps/", "#{HOMEBREW_CACHE}/") &&
            (path_string.include?("/") || path_string.end_with?(".rb"))
           raise <<~WARNING
-            Rejecting formula at #{!path_realpath} because it's not in a tap.
+            Rejecting formula at #{path_string} because it's not in a tap.
                    Homebrew requires formulae to be in a tap.
 
             To create a tap, run e.g.