diff --git a/ext/filemagic/extconf.rb b/ext/filemagic/extconf.rb
index 158cea4..59f949c 100644
--- a/ext/filemagic/extconf.rb
+++ b/ext/filemagic/extconf.rb
@@ -1,31 +1,20 @@
 require 'mkmf'
 
-HEADER_DIRS = [
-  '/opt/local/include', # MacPorts
-  '/usr/local/include', # compiled from source and Homebrew
-  '/opt/homebrew/include', # compiled from source and Homebrew (ARM based Macs)
-  '/usr/include',       # system
-]
-
-LIB_DIRS = [
-  '/opt/local/lib', # MacPorts
-  '/usr/local/lib', # compiled from source and Homebrew
-  '/opt/homebrew/lib', # compiled from source and Homebrew (ARM based Macs)
-  '/usr/lib',       # system
-]
-
 $CFLAGS << ' -Wall' if ENV['WALL']
 $LDFLAGS << ' -static-libgcc' if RUBY_PLATFORM =~ /cygwin|mingw|mswin/
 
-dir_config('magic', HEADER_DIRS, LIB_DIRS)
-dir_config('gnurx', HEADER_DIRS, LIB_DIRS)
-
-have_library('gnurx')
+dir_config('magic')
+dir_config('gnurx')
 
-if have_library('magic', 'magic_open') && have_header('magic.h')
-  have_func('magic_version')
-  have_header('file/patchlevel.h')
-  create_makefile('filemagic/ruby_filemagic')
+if have_library('magic', 'magic_open')
+  if have_header('magic.h')
+    have_library('gnurx')
+    have_func('magic_version')
+    have_header('file/patchlevel.h')
+    create_makefile('filemagic/ruby_filemagic')
+  else
+    abort '*** ERROR: missing magic.h (required to compile this module)'
+  end
 else
-  abort '*** ERROR: missing required library to compile this module'
+  abort '*** ERROR: missing magic library (required to build this module)'
 end