diff --git a/Library/Homebrew/macos.rb b/Library/Homebrew/macos.rb
index 19c33bbc9d..62c7e601cc 100644
--- a/Library/Homebrew/macos.rb
+++ b/Library/Homebrew/macos.rb
@@ -65,7 +65,8 @@ module MacOS extend self
     @dev_tools_path ||= if File.exist? "/usr/bin/cc" and File.exist? "/usr/bin/make"
       # probably a safe enough assumption (the unix way)
       Pathname.new "/usr/bin"
-    elsif not Xcode.bad_xcode_select_path? and system "/usr/bin/xcrun -find make 1>/dev/null 2>&1"
+    # Note that the exit status of system "xcrun foo" isn't always accurate
+    elsif not Xcode.bad_xcode_select_path? and not `/usr/bin/xcrun -find make 2>/dev/null`.empty?
       # Wherever "make" is there are the dev tools.
       Pathname.new(`/usr/bin/xcrun -find make`.chomp).dirname
     elsif File.exist? "#{Xcode.prefix}/usr/bin/make"