Retrieved 2023-03-05 from
https://sources.debian.org/data/main/r/ruby-hiredis/0.6.3-2/debian/patches/use_system_libhiredis.patch.

From: Apollon Oikonomopoulos <apoikos@gmail.com>
Date: Mon, 20 Jan 2020 09:28:45 -0300
Subject: Use system libhiredis

Last-Update: 2013-04-10
Forwarded: no

Use Debian's libhiredis version instead of downloading one and statically
linking against it.
---
 ext/hiredis_ext/extconf.rb | 18 +++---------------
 1 file changed, 3 insertions(+), 15 deletions(-)

diff --git a/ext/hiredis_ext/extconf.rb b/ext/hiredis_ext/extconf.rb
index da39eb5..ffa3abf 100644
--- a/ext/hiredis_ext/extconf.rb
+++ b/ext/hiredis_ext/extconf.rb
@@ -9,12 +9,6 @@ end
 
 RbConfig::MAKEFILE_CONFIG['CC'] = ENV['CC'] if ENV['CC']
 
-hiredis_dir = File.join(File.dirname(__FILE__), %w{.. .. vendor hiredis})
-unless File.directory?(hiredis_dir)
-  STDERR.puts "vendor/hiredis missing, please checkout its submodule..."
-  exit 1
-end
-
 RbConfig::CONFIG['configure_args'] =~ /with-make-prog\=(\w+)/
 make_program = $1 || ENV['make']
 make_program ||= case RUBY_PLATFORM
@@ -27,15 +21,9 @@ else
 end
 
 if build_hiredis
-  # Make sure hiredis is built...
-  Dir.chdir(hiredis_dir) do
-    success = system("#{make_program} static")
-    raise "Building hiredis failed" if !success
-  end
-
-  # Statically link to hiredis (mkmf can't do this for us)
-  $CFLAGS << " -I#{hiredis_dir}"
-  $LDFLAGS << " #{hiredis_dir}/libhiredis.a"
+  # Debian: use system hiredis
+  $CFLAGS << " -I/usr/include/hiredis"
+  $LDFLAGS << " -lhiredis"
 
   have_func("rb_thread_fd_select")
   create_makefile('hiredis/ext/hiredis_ext')