diff --git a/Library/Homebrew/formula_installer.rb b/Library/Homebrew/formula_installer.rb
index 44e57c7303f6074a431660e8243fe4346bdc7a5c..9557ac33ad12057915d436085b4f31878e159a65 100644
--- a/Library/Homebrew/formula_installer.rb
+++ b/Library/Homebrew/formula_installer.rb
@@ -459,6 +459,7 @@ class FormulaInstaller
       puts "Homebrew requires that man pages live under share."
       puts 'This can often be fixed by passing "--mandir=#{man}" to configure.'
       @show_summary_heading = true
+      Homebrew.failed = true # fatal to Brew Bot
     end
   end