Make sure all exceptions are sent back to the parent process

Library/Homebrew/build.rb

@@ -176,6 +176,7 @@ class Build
   end
 end
 
+begin
   error_pipe = IO.new(ENV["HOMEBREW_ERROR_PIPE"].to_i, "w")
   error_pipe.fcntl(Fcntl::F_SETFD, Fcntl::FD_CLOEXEC)
 
@@ -184,7 +185,6 @@ system "/usr/bin/sudo", "-k"
 
   trap("INT", old_trap)
 
-begin
   formula = ARGV.formulae.first
   options = Options.create(ARGV.options_only)
   build   = Build.new(formula, options)