From f4663b342ee1c5f2e63f71a5394c9cdf42b8766f Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Tue, 13 Oct 2020 08:06:31 -0400
Subject: [PATCH 01/33] cleanup: no need to check for HAVE_RUBY_UTIL_H in C
 extension

which was introduced in ruby v1_9_0_3
---
 ext/nokogiri/nokogiri.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/ext/nokogiri/nokogiri.c b/ext/nokogiri/nokogiri.c
index 740b30d5a0..292ffee358 100644
--- a/ext/nokogiri/nokogiri.c
+++ b/ext/nokogiri/nokogiri.c
@@ -33,11 +33,7 @@ void vasprintf_free (void *p)
   free(p);
 }
 
-#ifdef HAVE_RUBY_UTIL_H
 #include "ruby/util.h"
-#else
-#include "util.h"
-#endif
 
 void nokogiri_root_node(xmlNodePtr node)
 {

From d2165e6024cd9a9152631a08e04fa2f96b0b2826 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 12 Oct 2020 16:10:56 -0400
Subject: [PATCH 02/33] info: add libxml2 version information to extconf
 have_func calls

this will be useful to do some cleanup when we eventually decide to
bump our libxml2 dependency.
---
 ext/nokogiri/extconf.rb | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index 89c6ec56d8..7c8b447f72 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -675,13 +675,12 @@ def configure
     asplode("lib#{lib}")
 end
 
-have_func('xmlHasFeature') or abort "xmlHasFeature() is missing."
-have_func('xmlFirstElementChild')
-have_func('xmlRelaxNGSetParserStructuredErrors')
-have_func('xmlRelaxNGSetParserStructuredErrors')
-have_func('xmlRelaxNGSetValidStructuredErrors')
-have_func('xmlSchemaSetValidStructuredErrors')
-have_func('xmlSchemaSetParserStructuredErrors')
+have_func('xmlHasFeature') or abort "xmlHasFeature() is missing." # introduced in libxml 2.6.21
+have_func('xmlFirstElementChild') # introduced in libxml 2.7.3
+have_func('xmlRelaxNGSetParserStructuredErrors') # introduced in libxml 2.6.24
+have_func('xmlRelaxNGSetValidStructuredErrors') # introduced in libxml 2.6.21
+have_func('xmlSchemaSetValidStructuredErrors') # introduced in libxml 2.6.23
+have_func('xmlSchemaSetParserStructuredErrors') # introduced in libxml 2.6.23
 
 create_makefile('nokogiri/nokogiri')
 

From 3d9a23a0ee7a2b5854ede170e645a0825306aa84 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 12 Oct 2020 16:30:53 -0400
Subject: [PATCH 03/33] cleanup: use have_func to check for vasprintf

and
- remove platform-specific "-D" flags
- remove `vasprintf_free`
- change calls to `vasprintf_free` to call `free`
- whitespace
---
 ext/nokogiri/extconf.rb          |  7 ++---
 ext/nokogiri/nokogiri.c          | 10 ++-----
 ext/nokogiri/nokogiri.h          | 48 +++++++++++++++-----------------
 ext/nokogiri/xml_sax_parser.c    |  7 ++---
 ext/nokogiri/xml_xpath_context.c |  2 --
 ext/nokogiri/xslt_stylesheet.c   |  5 +---
 6 files changed, 29 insertions(+), 50 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index 7c8b447f72..861dd6545a 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -421,11 +421,7 @@ def using_system_libraries?
 add_cflags(ENV["CFLAGS"])
 
 if windows?
-  $CFLAGS << " -DXP_WIN -DXP_WIN32 -DUSE_INCLUDED_VASPRINTF"
-end
-
-if solaris? || aix?
-  $CFLAGS << " -DUSE_INCLUDED_VASPRINTF"
+  $CFLAGS << " -DXP_WIN -DXP_WIN32"
 end
 
 if darwin?
@@ -675,6 +671,7 @@ def configure
     asplode("lib#{lib}")
 end
 
+have_func('vasprintf')
 have_func('xmlHasFeature') or abort "xmlHasFeature() is missing." # introduced in libxml 2.6.21
 have_func('xmlFirstElementChild') # introduced in libxml 2.7.3
 have_func('xmlRelaxNGSetParserStructuredErrors') # introduced in libxml 2.6.24
diff --git a/ext/nokogiri/nokogiri.c b/ext/nokogiri/nokogiri.c
index 292ffee358..b68cd5866a 100644
--- a/ext/nokogiri/nokogiri.c
+++ b/ext/nokogiri/nokogiri.c
@@ -7,12 +7,11 @@ VALUE mNokogiriXslt ;
 VALUE mNokogiriXmlSax ;
 VALUE mNokogiriHtmlSax ;
 
-#ifdef USE_INCLUDED_VASPRINTF
+#ifndef HAVE_VASPRINTF
 /*
- * I srsly hate windows.  it doesn't have vasprintf.
  * Thank you Geoffroy Couprie for this implementation of vasprintf!
  */
-int vasprintf (char **strp, const char *fmt, va_list ap)
+int vasprintf(char **strp, const char *fmt, va_list ap)
 {
   /* Mingw32/64 have a broken vsnprintf implementation that fails when
    * using a zero-byte limit in order to retrieve the required size for malloc.
@@ -28,11 +27,6 @@ int vasprintf (char **strp, const char *fmt, va_list ap)
 }
 #endif
 
-void vasprintf_free (void *p)
-{
-  free(p);
-}
-
 #include "ruby/util.h"
 
 void nokogiri_root_node(xmlNodePtr node)
diff --git a/ext/nokogiri/nokogiri.h b/ext/nokogiri/nokogiri.h
index 2dad57633b..f4e9177b2c 100644
--- a/ext/nokogiri/nokogiri.h
+++ b/ext/nokogiri/nokogiri.h
@@ -2,31 +2,24 @@
 #define NOKOGIRI_NATIVE
 
 #if _MSC_VER
-#ifndef WIN32_LEAN_AND_MEAN
-#define WIN32_LEAN_AND_MEAN
-#endif /* WIN32_LEAN_AND_MEAN */
-#ifndef WIN32
-#define WIN32
-#endif /* WIN32 */
-#include <winsock2.h>
-#include <ws2tcpip.h>
-#include <windows.h>
+#  ifndef WIN32_LEAN_AND_MEAN
+#    define WIN32_LEAN_AND_MEAN
+#  endif /* WIN32_LEAN_AND_MEAN */
+
+#  ifndef WIN32
+#    define WIN32
+#  endif /* WIN32 */
+
+#  include <winsock2.h>
+#  include <ws2tcpip.h>
+#  include <windows.h>
 #endif
 
 #include <stdlib.h>
 #include <string.h>
 #include <assert.h>
 #include <stdarg.h>
-
-#ifdef USE_INCLUDED_VASPRINTF
-int vasprintf (char **strp, const char *fmt, va_list ap);
-#else
-
-#define _GNU_SOURCE
-#  include <stdio.h>
-#undef _GNU_SOURCE
-
-#endif
+#include <stdio.h>
 
 #include <libxml/parser.h>
 #include <libxml/entities.h>
@@ -43,6 +36,7 @@ int vasprintf (char **strp, const char *fmt, va_list ap);
 #include <libxslt/extensions.h>
 #include <libxslt/xsltconfig.h>
 #include <libxml/c14n.h>
+
 #include <ruby.h>
 #include <ruby/st.h>
 #include <ruby/encoding.h>
@@ -106,25 +100,27 @@ extern VALUE mNokogiriHtml ;
 extern VALUE mNokogiriHtmlSax ;
 extern VALUE mNokogiriXslt ;
 
+int vasprintf(char **strp, const char *fmt, va_list ap);
+
 void nokogiri_root_node(xmlNodePtr);
 void nokogiri_root_nsdef(xmlNsPtr, xmlDocPtr);
 
 #ifdef DEBUG
 
-#define NOKOGIRI_DEBUG_START(p) if (getenv("NOKOGIRI_NO_FREE")) return ; if (getenv("NOKOGIRI_DEBUG")) fprintf(stderr,"nokogiri: %s:%d %p start\n", __FILE__, __LINE__, p);
-#define NOKOGIRI_DEBUG_END(p) if (getenv("NOKOGIRI_DEBUG")) fprintf(stderr,"nokogiri: %s:%d %p end\n", __FILE__, __LINE__, p);
+#  define NOKOGIRI_DEBUG_START(p) if (getenv("NOKOGIRI_NO_FREE")) return ; if (getenv("NOKOGIRI_DEBUG")) fprintf(stderr,"nokogiri: %s:%d %p start\n", __FILE__, __LINE__, p);
+#  define NOKOGIRI_DEBUG_END(p) if (getenv("NOKOGIRI_DEBUG")) fprintf(stderr,"nokogiri: %s:%d %p end\n", __FILE__, __LINE__, p);
 
 #else
 
-#define NOKOGIRI_DEBUG_START(p)
-#define NOKOGIRI_DEBUG_END(p)
+#  define NOKOGIRI_DEBUG_START(p)
+#  define NOKOGIRI_DEBUG_END(p)
 
 #endif
 
 #ifndef __builtin_expect
-# if defined(__GNUC__)
-#  define __builtin_expect(expr, c) __builtin_expect((long)(expr), (long)(c))
-# endif
+#  if defined(__GNUC__)
+#    define __builtin_expect(expr, c) __builtin_expect((long)(expr), (long)(c))
+#  endif
 #endif
 
 #define XMLNS_PREFIX "xmlns"
diff --git a/ext/nokogiri/xml_sax_parser.c b/ext/nokogiri/xml_sax_parser.c
index 1a5f6c5f51..0c7d45ec30 100644
--- a/ext/nokogiri/xml_sax_parser.c
+++ b/ext/nokogiri/xml_sax_parser.c
@@ -1,8 +1,5 @@
 #include <xml_sax_parser.h>
 
-int vasprintf (char **strp, const char *fmt, va_list ap);
-void vasprintf_free (void *p);
-
 static ID id_start_document, id_end_document, id_start_element, id_end_element;
 static ID id_start_element_namespace, id_end_element_namespace;
 static ID id_comment, id_characters, id_xmldecl, id_error, id_warning;
@@ -206,7 +203,7 @@ static void warning_func(void * ctx, const char *msg, ...)
   va_end(args);
 
   ruby_message = NOKOGIRI_STR_NEW2(message);
-  vasprintf_free(message);
+  free(message);
   rb_funcall(doc, id_warning, 1, ruby_message);
 }
 
@@ -223,7 +220,7 @@ static void error_func(void * ctx, const char *msg, ...)
   va_end(args);
 
   ruby_message = NOKOGIRI_STR_NEW2(message);
-  vasprintf_free(message);
+  free(message);
   rb_funcall(doc, id_error, 1, ruby_message);
 }
 
diff --git a/ext/nokogiri/xml_xpath_context.c b/ext/nokogiri/xml_xpath_context.c
index cb1be24b72..94f47f640b 100644
--- a/ext/nokogiri/xml_xpath_context.c
+++ b/ext/nokogiri/xml_xpath_context.c
@@ -1,7 +1,5 @@
 #include <xml_xpath_context.h>
 
-int vasprintf (char **strp, const char *fmt, va_list ap);
-
 static void deallocate(xmlXPathContextPtr ctx)
 {
   NOKOGIRI_DEBUG_START(ctx);
diff --git a/ext/nokogiri/xslt_stylesheet.c b/ext/nokogiri/xslt_stylesheet.c
index 779294badd..73b975044e 100644
--- a/ext/nokogiri/xslt_stylesheet.c
+++ b/ext/nokogiri/xslt_stylesheet.c
@@ -7,9 +7,6 @@
 
 VALUE xslt;
 
-int vasprintf (char **strp, const char *fmt, va_list ap);
-void vasprintf_free (void *p);
-
 static void mark(nokogiriXsltStylesheetTuple *wrapper)
 {
   rb_gc_mark(wrapper->func_instances);
@@ -37,7 +34,7 @@ static void xslt_generic_error_handler(void * ctx, const char *msg, ...)
 
   rb_str_cat2((VALUE)ctx, message);
 
-  vasprintf_free(message);
+  free(message);
 }
 
 VALUE Nokogiri_wrap_xslt_stylesheet(xsltStylesheetPtr ss)

From 0655f76400a174bf8241d0b77e64f1cb0434d83c Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 12 Oct 2020 16:41:02 -0400
Subject: [PATCH 04/33] cleanup: fix xml_node.c type cast warning

---
 ext/nokogiri/xml_node.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ext/nokogiri/xml_node.c b/ext/nokogiri/xml_node.c
index 3cde12ad67..e0beb8b36e 100644
--- a/ext/nokogiri/xml_node.c
+++ b/ext/nokogiri/xml_node.c
@@ -301,7 +301,7 @@ static VALUE reparent_node_with(VALUE pivot_obj, VALUE reparentee_obj, pivot_rep
        *  issue #391, where new node's prefix may become the string "default"
        *  see libxml2 tree.c xmlNewReconciliedNs which implements this behavior.
        */
-      xmlFree(reparentee->ns->prefix);
+      xmlFree((xmlChar*)reparentee->ns->prefix);
       reparentee->ns->prefix = NULL;
     }
   }

From a76b93effa4b9754e0705b1e1c6f7f0d53eb5383 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 19 Oct 2020 14:47:18 -0400
Subject: [PATCH 05/33] cleanup(extconf): document sdk cppflag on macos

and clean up the logic to only do this when using system libraries and
the directory exists.
---
 ext/nokogiri/extconf.rb | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index 861dd6545a..c2451c0b07 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -397,8 +397,10 @@ def using_system_libraries?
   do_clean
 end
 
-if darwin?
-  ENV['CFLAGS'] = "#{ENV['CFLAGS']} -I /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/libxml2"
+# Add SDK-specific include path for macOS and brew versions before v2.2.12 (2020-04-08) [#1851, #1801]
+macos_mojave_sdk_include_path = "/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/libxml2"
+if using_system_libraries? && darwin? && Dir.exist?(macos_mojave_sdk_include_path)
+   ENV['CFLAGS'] = "#{ENV['CFLAGS']} -I #{macos_mojave_sdk_include_path}"
 end
 
 if openbsd? && !using_system_libraries?

From 2b9d3e2f14c85647f703ddd92177c66bb824913f Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 19 Oct 2020 15:24:43 -0400
Subject: [PATCH 06/33] cleanup(extconf): omit unnecessary try_compile wrapper

---
 ext/nokogiri/extconf.rb | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index c2451c0b07..bedc7b9e00 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -138,10 +138,6 @@ def package_config pkg, options={}
   end
 end
 
-def nokogiri_try_compile
-  try_compile "int main() {return 0;}", "", {werror: true}
-end
-
 def check_libxml_version version=nil
   source = if version.nil?
              <<-SRC
@@ -163,7 +159,7 @@ def check_libxml_version version=nil
 def add_cflags(flags)
   print "checking if the C compiler accepts #{flags}... "
   with_cflags("#{$CFLAGS} #{flags}") do
-    if nokogiri_try_compile
+    if try_compile("int main() {return 0;}", "", {werror: true})
       puts 'yes'
       true
     else

From 426fd687534bee9c0c6bdb1d51f2a92c1edc87ce Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 19 Oct 2020 16:13:19 -0400
Subject: [PATCH 07/33] cleanup(extconf): rename ROOT to PACKAGE_ROOT_DIR

---
 ext/nokogiri/extconf.rb | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index bedc7b9e00..b326a63b53 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -3,11 +3,9 @@
 
 require 'mkmf'
 
-ROOT = File.expand_path(File.join(File.dirname(__FILE__), '..', '..'))
+PACKAGE_ROOT_DIR = File.expand_path(File.join(File.dirname(__FILE__), '..', '..'))
 
-#
-# functions
-#
+# utility functions
 def windows?
   RbConfig::CONFIG['target_os'] =~ /mingw32|mswin/
 end
@@ -88,7 +86,7 @@ def do_clean
   require 'pathname'
   require 'fileutils'
 
-  root = Pathname(ROOT)
+  root = Pathname(PACKAGE_ROOT_DIR)
   pwd  = Pathname(Dir.pwd)
 
   # Skip if this is a development work tree
@@ -260,11 +258,11 @@ def chdir_for_build
 
 def process_recipe(name, version, static_p, cross_p)
   MiniPortile.new(name, version).tap do |recipe|
-    recipe.target = File.join(ROOT, "ports")
+    recipe.target = File.join(PACKAGE_ROOT_DIR, "ports")
     # Prefer host_alias over host in order to use i586-mingw32msvc as
     # correct compiler prefix for cross build, but use host if not set.
     recipe.host = RbConfig::CONFIG["host_alias"].empty? ? RbConfig::CONFIG["host"] : RbConfig::CONFIG["host_alias"]
-    recipe.patch_files = Dir[File.join(ROOT, "patches", name, "*.patch")].sort
+    recipe.patch_files = Dir[File.join(PACKAGE_ROOT_DIR, "patches", name, "*.patch")].sort
     recipe.configure_options << "--libdir=#{File.join(recipe.path, "lib")}"
 
     yield recipe
@@ -476,7 +474,7 @@ def using_system_libraries?
 
   dir_config('zlib')
 
-  dependencies = YAML.load_file(File.join(ROOT, "dependencies.yml"))
+  dependencies = YAML.load_file(File.join(PACKAGE_ROOT_DIR, "dependencies.yml"))
 
   cross_build_p = enable_config("cross-build")
   if cross_build_p || windows?
@@ -612,7 +610,7 @@ def configure
           case arg
           when /\A-L(.+)\z/
             # Prioritize ports' directories
-            if $1.start_with?(ROOT + '/')
+            if $1.start_with?(PACKAGE_ROOT_DIR + '/')
               $LIBPATH = [$1] | $LIBPATH
             else
               $LIBPATH = $LIBPATH | [$1]

From 652c6fdfcaf2cf6bb10746eda8b7e4598a407689 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 19 Oct 2020 16:17:41 -0400
Subject: [PATCH 08/33] cleanup(extconf): extract constants for libxml required
 versions

and rename and reformat the helper function
---
 ext/nokogiri/extconf.rb | 28 ++++++++++++++++------------
 1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index b326a63b53..3e1b01d824 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -4,6 +4,8 @@
 require 'mkmf'
 
 PACKAGE_ROOT_DIR = File.expand_path(File.join(File.dirname(__FILE__), '..', '..'))
+REQUIRED_LIBXML_VERSION = "2.6.21"
+RECOMMENDED_LIBXML_VERSION = "2.9.3"
 
 # utility functions
 def windows?
@@ -136,18 +138,18 @@ def package_config pkg, options={}
   end
 end
 
-def check_libxml_version version=nil
+def have_libxml_headers?(version=nil)
   source = if version.nil?
-             <<-SRC
-#include <libxml/xmlversion.h>
+             <<~SRC
+               #include <libxml/xmlversion.h>
              SRC
            else
              version_int = sprintf "%d%2.2d%2.2d", *(version.split("."))
-             <<-SRC
-#include <libxml/xmlversion.h>
-#if LIBXML_VERSION < #{version_int}
-#error libxml2 is older than #{version}
-#endif
+             <<~SRC
+               #include <libxml/xmlversion.h>
+               #if LIBXML_VERSION < #{version_int}
+               #  error libxml2 is older than #{version}
+               #endif
              SRC
            end
 
@@ -453,10 +455,12 @@ def using_system_libraries?
   dir_config('xslt').any?  or package_config('libxslt')
   dir_config('exslt').any? or package_config('libexslt')
 
-  check_libxml_version or abort "ERROR: cannot discover where libxml2 is located on your system. please make sure `pkg-config` is installed."
-  check_libxml_version("2.6.21") or abort "ERROR: libxml2 version 2.6.21 or later is required!"
-  check_libxml_version("2.9.3") or warn "WARNING: libxml2 version 2.9.3 or later is highly recommended, but proceeding anyway."
-
+  have_libxml_headers? or
+    abort "ERROR: cannot discover where libxml2 is located on your system. please make sure `pkg-config` is installed."
+  have_libxml_headers?(REQUIRED_LIBXML_VERSION) or
+    abort "ERROR: libxml2 version #{REQUIRED_LIBXML_VERSION} or later is required!"
+  have_libxml_headers?(RECOMMENDED_LIBXML_VERSION) or
+    warn "WARNING: libxml2 version #{RECOMMENDED_LIBXML_VERSION} or later is highly recommended, but proceeding anyway."
 else
   message "Building nokogiri using packaged libraries.\n"
 

From 8c17803caa60a2b77452346491d543f2840b1122 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 19 Oct 2020 18:07:34 -0400
Subject: [PATCH 09/33] cleanup(extconf): extract mini_portile required version

---
 ext/nokogiri/extconf.rb | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index 3e1b01d824..e311752c1c 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -3,11 +3,20 @@
 
 require 'mkmf'
 
+#
+#  helpful constants
+#
 PACKAGE_ROOT_DIR = File.expand_path(File.join(File.dirname(__FILE__), '..', '..'))
 REQUIRED_LIBXML_VERSION = "2.6.21"
 RECOMMENDED_LIBXML_VERSION = "2.9.3"
 
-# utility functions
+# The gem version constraint in the Rakefile is not respected at install time.
+# Keep this version in sync with the one in the Rakefile !
+REQUIRED_MINI_PORTILE_VERSION = "~> 2.5.0"
+
+#
+#  utility functions
+#
 def windows?
   RbConfig::CONFIG['target_os'] =~ /mingw32|mswin/
 end
@@ -464,10 +473,8 @@ def using_system_libraries?
 else
   message "Building nokogiri using packaged libraries.\n"
 
-  # The gem version constraint in the Rakefile is not respected at install time.
-  # Keep this version in sync with the one in the Rakefile !
   require 'rubygems'
-  gem 'mini_portile2', '~> 2.5.0'
+  gem 'mini_portile2', REQUIRED_MINI_PORTILE_VERSION
   require 'mini_portile2'
   message "Using mini_portile version #{MiniPortile::VERSION}\n"
 

From 0f093e8ef80c285171331c250683b22d920dd1d2 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 19 Oct 2020 16:20:23 -0400
Subject: [PATCH 10/33] cleanup(extconf): indent all heredocs with `<<~`

---
 ext/nokogiri/extconf.rb | 140 ++++++++++++++++++----------------------
 1 file changed, 63 insertions(+), 77 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index e311752c1c..ff68242275 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -63,33 +63,33 @@ def sh_export_path path
 end
 
 def do_help
-  print <<HELP
-usage: ruby #{$0} [options]
+  print <<~HELP
+    usage: ruby #{$0} [options]
 
-    --disable-clean
-        Do not clean out intermediate files after successful build.
+        --disable-clean
+            Do not clean out intermediate files after successful build.
 
-    --disable-static
-        Do not statically link bundled libraries.
+        --disable-static
+            Do not statically link bundled libraries.
 
-    --with-iconv-dir=DIR
-        Use the iconv library placed under DIR.
+        --with-iconv-dir=DIR
+            Use the iconv library placed under DIR.
 
-    --with-zlib-dir=DIR
-        Use the zlib library placed under DIR.
+        --with-zlib-dir=DIR
+            Use the zlib library placed under DIR.
 
-    --use-system-libraries
-        Use system libraries instead of building and using the bundled
-        libraries.
+        --use-system-libraries
+            Use system libraries instead of building and using the bundled
+            libraries.
 
-    --with-xml2-dir=DIR / --with-xml2-config=CONFIG
-    --with-xslt-dir=DIR / --with-xslt-config=CONFIG
-    --with-exslt-dir=DIR / --with-exslt-config=CONFIG
-        Use libxml2/libxslt/libexslt as specified.
+        --with-xml2-dir=DIR / --with-xml2-config=CONFIG
+        --with-xslt-dir=DIR / --with-xslt-config=CONFIG
+        --with-exslt-dir=DIR / --with-exslt-config=CONFIG
+            Use libxml2/libxslt/libexslt as specified.
 
-    --enable-cross-build
-        Do cross-build.
-HELP
+        --enable-cross-build
+            Do cross-build.
+  HELP
   exit! 0
 end
 
@@ -202,16 +202,15 @@ def have_iconv?(using = nil)
       preserving_globals do
         yield if block_given?
 
-        try_link(<<-'SRC', opt)
-#include <stdlib.h>
-#include <iconv.h>
-
-int main(void)
-{
-    iconv_t cd = iconv_open("", "");
-    iconv(cd, NULL, NULL, NULL, NULL);
-    return EXIT_SUCCESS;
-}
+        try_link(<<~'SRC', opt)
+          #include <stdlib.h>
+          #include <iconv.h>
+          int main(void)
+          {
+              iconv_t cd = iconv_open("", "");
+              iconv(cd, NULL, NULL, NULL, NULL);
+              return EXIT_SUCCESS;
+          }
         SRC
       end
     end
@@ -326,47 +325,35 @@ def process_recipe(name, version, static_p, cross_p)
       "#{key}=#{value}"
     end
 
-    message <<-"EOS"
-************************************************************************
-IMPORTANT NOTICE:
-
-Building Nokogiri with a packaged version of #{name}-#{version}#{'.' if recipe.patch_files.empty?}
-    EOS
+    message <<~EOM
+      ---------- IMPORTANT NOTICE ----------
+      Building Nokogiri with a packaged version of #{name}-#{version}#{'.' if recipe.patch_files.empty?}
+    EOM
 
     unless recipe.patch_files.empty?
       message "with the following patches applied:\n"
 
       recipe.patch_files.each do |patch|
-        message "\t- %s\n" % File.basename(patch)
+        message "  - %s\n" % File.basename(patch)
       end
     end
 
-    message <<-"EOS"
+    message <<~EOM
 
-Team Nokogiri will keep on doing their best to provide security
-updates in a timely manner, but if this is a concern for you and want
-to use the system library instead; abort this installation process and
-reinstall nokogiri as follows:
+      The Nokogiri maintainers intend to provide timely security updates, but if
+      this is a concern for you and want to use your OS/distro system library
+      instead, then abort this installation process and install nokogiri as
+      instructed at:
 
-    gem install nokogiri -- --use-system-libraries
-        [--with-xml2-config=/path/to/xml2-config]
-        [--with-xslt-config=/path/to/xslt-config]
+          https://nokogiri.org/tutorials/installing_nokogiri.html#install-with-system-libraries
 
-If you are using Bundler, tell it to use the option:
+    EOM
 
-    bundle config build.nokogiri --use-system-libraries
-    bundle install
-    EOS
+    message <<~EOM if name == 'libxml2'
+      Note, however, that nokogiri cannot guarantee compatiblity with every
+      version of libxml2 that may be provided by OS/package vendors.
 
-    message <<-"EOS" if name == 'libxml2'
-
-Note, however, that nokogiri is not fully compatible with arbitrary
-versions of libxml2 provided by OS/package vendors.
-    EOS
-
-    message <<-"EOS"
-************************************************************************
-    EOS
+    EOM
 
     checkpoint = "#{recipe.target}/#{recipe.name}-#{recipe.version}-#{recipe.host}.installed"
     unless File.exist?(checkpoint)
@@ -451,8 +438,7 @@ def using_system_libraries?
   $CFLAGS << " -Wall -Wcast-qual -Wwrite-strings -Wmissing-noreturn -Winline"
 end
 
-case
-when using_system_libraries?
+if using_system_libraries?
   message "Building nokogiri using system libraries.\n"
 
   dir_config('zlib')
@@ -551,18 +537,18 @@ def configure
     end
   else
     if darwin? && !have_header('iconv.h')
-      abort <<'EOM'.chomp
------
-The file "iconv.h" is missing in your build environment,
-which means you haven't installed Xcode Command Line Tools properly.
-
-To install Command Line Tools, try running `xcode-select --install` on
-terminal and follow the instructions.  If it fails, open Xcode.app,
-select from the menu "Xcode" - "Open Developer Tool" - "More Developer
-Tools" to open the developer site, download the installer for your OS
-version and run it.
------
-EOM
+      abort <<~EOM.chomp
+        -----
+        The file "iconv.h" is missing in your build environment,
+        which means you haven't installed Xcode Command Line Tools properly.
+
+        To install Command Line Tools, try running `xcode-select --install` on
+        terminal and follow the instructions.  If it fails, open Xcode.app,
+        select from the menu "Xcode" - "Open Developer Tool" - "More Developer
+        Tools" to open the developer site, download the installer for your OS
+        version and run it.
+        -----
+      EOM
     end
   end
 
@@ -691,12 +677,12 @@ def configure
 if enable_config('clean', true)
   # Do not clean if run in a development work tree.
   File.open('Makefile', 'at') do |mk|
-    mk.print <<EOF
-all: clean-ports
+    mk.print <<~EOF
+      all: clean-ports
 
-clean-ports: $(DLLIB)
-	-$(Q)$(RUBY) $(srcdir)/extconf.rb --clean --#{static_p ? 'enable' : 'disable'}-static
-EOF
+      clean-ports: $(DLLIB)
+      \t-$(Q)$(RUBY) $(srcdir)/extconf.rb --clean --#{static_p ? 'enable' : 'disable'}-static
+    EOF
   end
 end
 

From 37db6c88731e0c3e2e95cfc37ee9d63e1fd7cf89 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 19 Oct 2020 18:08:14 -0400
Subject: [PATCH 11/33] cleanup(extconf): refactor sh_export_path

---
 ext/nokogiri/extconf.rb | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index ff68242275..571f4801ba 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -53,12 +53,13 @@ def sh_export_path path
   #
   # which is sh-compatible, in order to find things properly during
   # configuration
-  if windows?
-    match = Regexp.new("^([A-Z]):(/.*)").match(path)
-    if match && match.length == 3
-      return File.join("/", match[1], match[2])
-    end
+  return path if !windows?
+
+  match = Regexp.new("^([A-Z]):(/.*)").match(path)
+  if match && match.length == 3
+    return File.join("/", match[1], match[2])
   end
+
   path
 end
 

From 19489f173dd690e3a429f8c344fe1f19dd7f436c Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 19 Oct 2020 18:10:36 -0400
Subject: [PATCH 12/33] cleanup(extconf): comment and refactor package_config

---
 ext/nokogiri/extconf.rb | 30 ++++++++++++++++++++----------
 1 file changed, 20 insertions(+), 10 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index 571f4801ba..02c53a6c67 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -125,27 +125,37 @@ def do_clean
 end
 
 def package_config pkg, options={}
+  # use MakeMakefile#pkg_config, which uses the system utility `pkg-config`.
   package = pkg_config(pkg)
   return package if package
 
+  # only if that utility isn't found do we fall back to the pkg-config gem, and
+  # wrap it with the same logic as MakeMakefile#pkg_config
   begin
     require 'rubygems'
     gem 'pkg-config', (gem_ver='~> 1.1')
     require 'pkg-config' and message("Using pkg-config gem version #{PKGConfig::VERSION}\n")
   rescue LoadError
-    message "pkg-config could not be used to find #{pkg}\nPlease install either `pkg-config` or the pkg-config gem per\n\n    gem install pkg-config -v #{gem_ver.inspect}\n\n"
-  else
-    return nil unless PKGConfig.have_package(pkg)
-
-    cflags  = PKGConfig.cflags(pkg)
-    ldflags = PKGConfig.libs_only_L(pkg)
-    libs    = PKGConfig.libs_only_l(pkg)
+    message <<~EOM
+      pkg-config could not be used to find #{pkg}
+      Please install either `pkg-config` or the pkg-config gem per
 
-    Logging::message "PKGConfig package configuration for %s\n", pkg
-    Logging::message "cflags: %s\nldflags: %s\nlibs: %s\n\n", cflags, ldflags, libs
+          gem install pkg-config -v #{gem_ver.inspect}
 
-    [cflags, ldflags, libs]
+    EOM
+    return nil
   end
+
+  return nil unless PKGConfig.have_package(pkg)
+
+  cflags  = PKGConfig.cflags(pkg)
+  ldflags = PKGConfig.libs_only_L(pkg)
+  libs    = PKGConfig.libs_only_l(pkg)
+
+  Logging::message "PKGConfig package configuration for %s\n", pkg
+  Logging::message "cflags: %s\nldflags: %s\nlibs: %s\n\n", cflags, ldflags, libs
+
+  [cflags, ldflags, libs]
 end
 
 def have_libxml_headers?(version=nil)

From 90acd2e77aec5aa315e0a5b875ccb1dc59daf835 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 19 Oct 2020 18:11:21 -0400
Subject: [PATCH 13/33] cleanup(extconf): neaten preserving_globals

---
 ext/nokogiri/extconf.rb | 11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index 02c53a6c67..f3d58d7305 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -190,17 +190,10 @@ def add_cflags(flags)
 end
 
 def preserving_globals
-  values = [
-    $arg_config,
-    $CFLAGS, $CPPFLAGS,
-    $LDFLAGS, $LIBPATH, $libs
-  ].map(&:dup)
+  values = [$arg_config, $CFLAGS, $CPPFLAGS, $LDFLAGS, $LIBPATH, $libs].map(&:dup)
   yield
 ensure
-  $arg_config,
-  $CFLAGS, $CPPFLAGS,
-  $LDFLAGS, $LIBPATH, $libs =
-    values
+  $arg_config, $CFLAGS, $CPPFLAGS, $LDFLAGS, $LIBPATH, $libs = values
 end
 
 def asplode(lib)

From b011e658032b29bd68705468f55ddf5c9a43225e Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 19 Oct 2020 18:12:27 -0400
Subject: [PATCH 14/33] cleanup(extconf): neaten iconv_configure_flags

---
 ext/nokogiri/extconf.rb | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index f3d58d7305..d9c5bee94e 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -222,11 +222,10 @@ def have_iconv?(using = nil)
 end
 
 def iconv_configure_flags
-  # If --with-iconv-dir or --with-opt-dir is given, it should be
-  # the first priority
-  %w[iconv opt].each do |name|
-    if (config = preserving_globals { dir_config(name) }).any? &&
-        have_iconv?("--with-#{name}-* flags") { dir_config(name) }
+  # give --with-iconv-dir and --with-opt-dir first priority
+  ["iconv", "opt"].each do |target|
+    config = preserving_globals { dir_config(target) }
+    if config.any? && have_iconv?("--with-#{target}-* flags") { dir_config(target) }
       idirs, ldirs = config.map do |dirs|
         Array(dirs).flat_map do |dir|
           dir.split(File::PATH_SEPARATOR)
@@ -245,8 +244,8 @@ def iconv_configure_flags
     return ['--with-iconv=yes']
   end
 
-  if (config = preserving_globals { package_config('libiconv') }) &&
-     have_iconv?('pkg-config libiconv') { package_config('libiconv') }
+  config = preserving_globals { package_config('libiconv') }
+  if config && have_iconv?('pkg-config libiconv') { package_config('libiconv') }
     cflags, ldflags, libs = config
 
     return [

From 0e55b14e962c91fac2393bed4d9b9644d6286fbf Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 19 Oct 2020 18:14:30 -0400
Subject: [PATCH 15/33] cleanup(extconf): newlines, rename lib_a to
 libflag_to_filename

---
 ext/nokogiri/extconf.rb | 27 +++++++++++----------------
 1 file changed, 11 insertions(+), 16 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index d9c5bee94e..ea50dcb349 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -259,10 +259,10 @@ def iconv_configure_flags
   asplode "libiconv"
 end
 
-# When using rake-compiler-dock on Windows, the underlying Virtualbox shared
-# folders don't support symlinks, but libiconv expects it for a build on
-# Linux. We work around this limitation by using the temp dir for cooking.
 def chdir_for_build
+  # When using rake-compiler-dock on Windows, the underlying Virtualbox shared
+  # folders don't support symlinks, but libiconv expects it for a build on
+  # Linux. We work around this limitation by using the temp dir for cooking.
   build_dir = ENV['RCD_HOST_RUBY_PLATFORM'].to_s =~ /mingw|mswin|cygwin/ ? '/tmp' : '.'
   Dir.chdir(build_dir) do
     yield
@@ -369,7 +369,7 @@ def process_recipe(name, version, static_p, cross_p)
   end
 end
 
-def lib_a(ldflag)
+def libflag_to_filename(ldflag)
   case ldflag
   when /\A-l(.+)/
     "lib#{$1}.#{$LIBEXT}"
@@ -444,11 +444,8 @@ def using_system_libraries?
 if using_system_libraries?
   message "Building nokogiri using system libraries.\n"
 
+  # Using system libraries means we rely on the system libxml2 for iconv support (or not)
   dir_config('zlib')
-
-  # Using system libraries means we rely on the system libxml2 with
-  # regard to the iconv support.
-
   dir_config('xml2').any?  or package_config('libxml-2.0')
   dir_config('xslt').any?  or package_config('libxslt')
   dir_config('exslt').any? or package_config('libexslt')
@@ -459,6 +456,7 @@ def using_system_libraries?
     abort "ERROR: libxml2 version #{REQUIRED_LIBXML_VERSION} or later is required!"
   have_libxml_headers?(RECOMMENDED_LIBXML_VERSION) or
     warn "WARNING: libxml2 version #{RECOMMENDED_LIBXML_VERSION} or later is highly recommended, but proceeding anyway."
+
 else
   message "Building nokogiri using packaged libraries.\n"
 
@@ -556,9 +554,8 @@ def configure
   end
 
   unless windows?
-    preserving_globals {
-      have_library('z', 'gzdopen', 'zlib.h')
-    } or abort 'zlib is missing; necessary for building libxml2'
+    preserving_globals { have_library('z', 'gzdopen', 'zlib.h') } or
+      abort 'zlib is missing; necessary for building libxml2'
   end
 
   libxml2_recipe = process_recipe("libxml2", dependencies["libxml2"]["version"], static_p, cross_build_p) do |recipe|
@@ -596,9 +593,7 @@ def configure
   $LIBPATH = ["#{zlib_recipe.path}/lib"] | $LIBPATH if zlib_recipe
   $LIBPATH = ["#{libiconv_recipe.path}/lib"] | $LIBPATH if libiconv_recipe
 
-  have_lzma = preserving_globals {
-    have_library('lzma')
-  }
+  have_lzma = preserving_globals { have_library('lzma') }
 
   $libs = $libs.shellsplit.tap do |libs|
     [libxml2_recipe, libxslt_recipe].each do |recipe|
@@ -646,9 +641,9 @@ def configure
     $libs = $libs.shellsplit.map do |arg|
       case arg
       when '-lxml2'
-        File.join(libxml2_recipe.path, 'lib', lib_a(arg))
+        File.join(libxml2_recipe.path, 'lib', libflag_to_filename(arg))
       when '-lxslt', '-lexslt'
-        File.join(libxslt_recipe.path, 'lib', lib_a(arg))
+        File.join(libxslt_recipe.path, 'lib', libflag_to_filename(arg))
       else
         arg
       end

From 6d6e0173d6c1e45b3b14889abb18099a1ce4f4e7 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 19 Oct 2020 18:16:00 -0400
Subject: [PATCH 16/33] =?UTF-8?q?cleanup(extconf):=20rename=20asplode=20?=
 =?UTF-8?q?=E2=86=92=20abort=5Fcould=5Fnot=5Ffind=5Flibrary?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

and add verbosity to our have_func/have_library checks for libxml2,
libxslt, and libexslt.
---
 ext/nokogiri/extconf.rb | 27 +++++++++++++++------------
 1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index ea50dcb349..884e8324a7 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -196,7 +196,7 @@ def preserving_globals
   $arg_config, $CFLAGS, $CPPFLAGS, $LDFLAGS, $LIBPATH, $libs = values
 end
 
-def asplode(lib)
+def abort_could_not_find_library(lib)
   abort "-----\n#{lib} is missing.  Please locate mkmf.log to investigate how it is failing.\n-----"
 end
 
@@ -256,7 +256,7 @@ def iconv_configure_flags
     ]
   end
 
-  asplode "libiconv"
+  abort_could_not_find_library "libiconv"
 end
 
 def chdir_for_build
@@ -651,18 +651,21 @@ def configure
   end
 end
 
-{
-  "xml2"  => ['xmlParseDoc',            'libxml/parser.h'],
-  "xslt"  => ['xsltParseStylesheetDoc', 'libxslt/xslt.h'],
-  "exslt" => ['exsltFuncRegister',      'libexslt/exslt.h'],
-}.each do |lib, (func, header)|
-  have_func(func, header) ||
-  have_library(lib, func, header) ||
-  have_library("lib#{lib}", func, header) or
-    asplode("lib#{lib}")
+have_func('vasprintf')
+
+[
+  ["xml2", "xmlParseDoc", "libxml/parser.h"],
+  ["xslt", "xsltParseStylesheetDoc", "libxslt/xslt.h"],
+  ["exslt", "exsltFuncRegister", "libexslt/exslt.h"]
+].each do |lib, func, header|
+  checking_for "lib#{lib}" do
+    have_func(func, header) or
+      have_library(lib, func, header) or
+      have_library("lib#{lib}", func, header) or
+      abort_could_not_find_library("lib#{lib}")
+  end
 end
 
-have_func('vasprintf')
 have_func('xmlHasFeature') or abort "xmlHasFeature() is missing." # introduced in libxml 2.6.21
 have_func('xmlFirstElementChild') # introduced in libxml 2.7.3
 have_func('xmlRelaxNGSetParserStructuredErrors') # introduced in libxml 2.6.24

From bd7dacc1a13a154371e6f42deb2396764caaa388 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 19 Oct 2020 18:17:33 -0400
Subject: [PATCH 17/33] cleanup(extconf): simplify help/clean arg handling

---
 ext/nokogiri/extconf.rb | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index 884e8324a7..6d15f71c4d 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -382,21 +382,16 @@ def using_system_libraries?
 end
 
 #
-# main
+#  main
 #
 
-case
-when arg_config('--help')
-  do_help
-when arg_config('--clean')
-  do_clean
-end
-
 # Add SDK-specific include path for macOS and brew versions before v2.2.12 (2020-04-08) [#1851, #1801]
 macos_mojave_sdk_include_path = "/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/libxml2"
 if using_system_libraries? && darwin? && Dir.exist?(macos_mojave_sdk_include_path)
    ENV['CFLAGS'] = "#{ENV['CFLAGS']} -I #{macos_mojave_sdk_include_path}"
 end
+do_help if arg_config('--help')
+do_clean if arg_config('--clean')
 
 if openbsd? && !using_system_libraries?
   if `#{ENV['CC'] || '/usr/bin/cc'} -v 2>&1` !~ /clang/
@@ -409,6 +404,7 @@ def using_system_libraries?
 if ENV['CC']
   RbConfig::CONFIG['CC'] = RbConfig::MAKEFILE_CONFIG['CC'] = ENV['CC']
 end
+
 # use same c compiler for libxml and libxslt
 ENV['CC'] = RbConfig::CONFIG['CC']
 

From 3050fee6fe8ace67b448f084e09bdf61c61a3296 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 19 Oct 2020 18:23:34 -0400
Subject: [PATCH 18/33] cleanup(extconf): use append_*flags instead of
 add_cflags or globals

Also note that this commit removes -Wcast-qual and -Wwrite-strings
because I personally find them to be low-value and noisy.
---
 ext/nokogiri/extconf.rb | 48 ++++++++++++++++-------------------------
 1 file changed, 18 insertions(+), 30 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index 6d15f71c4d..a1a9659306 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -384,12 +384,6 @@ def using_system_libraries?
 #
 #  main
 #
-
-# Add SDK-specific include path for macOS and brew versions before v2.2.12 (2020-04-08) [#1851, #1801]
-macos_mojave_sdk_include_path = "/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/libxml2"
-if using_system_libraries? && darwin? && Dir.exist?(macos_mojave_sdk_include_path)
-   ENV['CFLAGS'] = "#{ENV['CFLAGS']} -I #{macos_mojave_sdk_include_path}"
-end
 do_help if arg_config('--help')
 do_clean if arg_config('--clean')
 
@@ -398,7 +392,7 @@ def using_system_libraries?
     ENV['CC'] ||= find_executable('egcc') or
       abort "Please install gcc 4.9+ from ports using `pkg_add -v gcc`"
   end
-  ENV['CFLAGS'] = "#{ENV['CFLAGS']} -I /usr/local/include"
+  append_cppflags "-I /usr/local/include"
 end
 
 if ENV['CC']
@@ -408,34 +402,28 @@ def using_system_libraries?
 # use same c compiler for libxml and libxslt
 ENV['CC'] = RbConfig::CONFIG['CC']
 
+append_cflags(ENV["CFLAGS"].split(/\s+/)) if !ENV["CFLAGS"].nil?
+append_cppflags(ENV["CPPFLAGS"].split(/\s+/)) if !ENV["CPPFLAGS"].nil?
+append_ldflags(ENV["LDFLAGS"].split(/\s+/)) if !ENV["LDFLAGS"].nil?
 $LIBS << " #{ENV["LIBS"]}"
 
-# Read CFLAGS from ENV and make sure compiling works.
-add_cflags(ENV["CFLAGS"])
-
-if windows?
-  $CFLAGS << " -DXP_WIN -DXP_WIN32"
-end
+append_cflags("-g") # always include debugging information
+append_cflags("-Winline") # we use at least one inline function in the C extension
+append_cflags("-Wmissing-noreturn") # good to have no matter what Ruby was compiled with
+# append_cflags(["-Wcast-qual", "-Wwrite-strings"]) # these tend to be noisy, but on occasion useful during development
+append_cflags("-Wno-error=unused-command-line-argument-hard-error-in-future") if darwin?
+append_cppflags("-DXP_UNIX") if nix?
+append_cppflags(["-DXP_WIN", "-DXP_WIN32"]) if windows?
 
-if darwin?
-  # Let Apple LLVM/clang 5.1 ignore unknown compiler flags
-  add_cflags("-Wno-error=unused-command-line-argument-hard-error-in-future")
-end
-
-if nix?
-  $CFLAGS << " -g -DXP_UNIX"
-end
-
-if RUBY_PLATFORM =~ /mingw/i
-  # Work around a character escaping bug in MSYS by passing an arbitrary
-  # double quoted parameter to gcc. See https://sourceforge.net/p/mingw/bugs/2142
-  $CPPFLAGS << ' "-Idummypath"'
+# Add SDK-specific include path for macOS and brew versions before v2.2.12 (2020-04-08) [#1851, #1801]
+macos_mojave_sdk_include_path = "/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/libxml2"
+if using_system_libraries? && darwin? && Dir.exist?(macos_mojave_sdk_include_path)
+  append_cppflags "-I #{macos_mojave_sdk_include_path}"
 end
 
-if RbConfig::CONFIG['CC'] =~ /gcc/
-  $CFLAGS << " -O3" unless $CFLAGS[/-O\d/]
-  $CFLAGS << " -Wall -Wcast-qual -Wwrite-strings -Wmissing-noreturn -Winline"
-end
+# Work around a character escaping bug in MSYS by passing an arbitrary
+# double quoted parameter to gcc. See https://sourceforge.net/p/mingw/bugs/2142
+append_cppflags(' "-Idummypath"') if windows?
 
 if using_system_libraries?
   message "Building nokogiri using system libraries.\n"

From 5c383ecf58fcdb69b1af53230f6d889b2043da96 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 19 Oct 2020 18:24:33 -0400
Subject: [PATCH 19/33] cleanup(extconf): remove unnecessary add_cflags method

---
 ext/nokogiri/extconf.rb | 13 -------------
 1 file changed, 13 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index a1a9659306..3f55a2be3a 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -176,19 +176,6 @@ def have_libxml_headers?(version=nil)
   try_cpp source
 end
 
-def add_cflags(flags)
-  print "checking if the C compiler accepts #{flags}... "
-  with_cflags("#{$CFLAGS} #{flags}") do
-    if try_compile("int main() {return 0;}", "", {werror: true})
-      puts 'yes'
-      true
-    else
-      puts 'no'
-      false
-    end
-  end
-end
-
 def preserving_globals
   values = [$arg_config, $CFLAGS, $CPPFLAGS, $LDFLAGS, $LIBPATH, $libs].map(&:dup)
   yield

From 433eeda403b914e6f33f4be76d31eb5ef398e769 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Tue, 20 Oct 2020 12:18:32 -0400
Subject: [PATCH 20/33] cleanup(extconf): rearrange methods and code

---
 ext/nokogiri/extconf.rb | 248 ++++++++++++++++++++--------------------
 1 file changed, 124 insertions(+), 124 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index 3f55a2be3a..199fce9a3e 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -41,89 +41,6 @@ def nix?
   ! (windows? || solaris? || darwin?)
 end
 
-def sh_export_path path
-  # because libxslt 1.1.29 configure.in uses AC_PATH_TOOL which treats ":"
-  # as a $PATH separator, we need to convert windows paths from
-  #
-  #   C:/path/to/foo
-  #
-  # to
-  #
-  #   /C/path/to/foo
-  #
-  # which is sh-compatible, in order to find things properly during
-  # configuration
-  return path if !windows?
-
-  match = Regexp.new("^([A-Z]):(/.*)").match(path)
-  if match && match.length == 3
-    return File.join("/", match[1], match[2])
-  end
-
-  path
-end
-
-def do_help
-  print <<~HELP
-    usage: ruby #{$0} [options]
-
-        --disable-clean
-            Do not clean out intermediate files after successful build.
-
-        --disable-static
-            Do not statically link bundled libraries.
-
-        --with-iconv-dir=DIR
-            Use the iconv library placed under DIR.
-
-        --with-zlib-dir=DIR
-            Use the zlib library placed under DIR.
-
-        --use-system-libraries
-            Use system libraries instead of building and using the bundled
-            libraries.
-
-        --with-xml2-dir=DIR / --with-xml2-config=CONFIG
-        --with-xslt-dir=DIR / --with-xslt-config=CONFIG
-        --with-exslt-dir=DIR / --with-exslt-config=CONFIG
-            Use libxml2/libxslt/libexslt as specified.
-
-        --enable-cross-build
-            Do cross-build.
-  HELP
-  exit! 0
-end
-
-def do_clean
-  require 'pathname'
-  require 'fileutils'
-
-  root = Pathname(PACKAGE_ROOT_DIR)
-  pwd  = Pathname(Dir.pwd)
-
-  # Skip if this is a development work tree
-  unless (root + '.git').exist?
-    message "Cleaning files only used during build.\n"
-
-    # (root + 'tmp') cannot be removed at this stage because
-    # nokogiri.so is yet to be copied to lib.
-
-    # clean the ports build directory
-    Pathname.glob(pwd.join('tmp', '*', 'ports')) do |dir|
-      FileUtils.rm_rf(dir, verbose: true)
-    end
-
-    if enable_config('static')
-      # ports installation can be safely removed if statically linked.
-      FileUtils.rm_rf(root + 'ports', verbose: true)
-    else
-      FileUtils.rm_rf(root + 'ports' + 'archives', verbose: true)
-    end
-  end
-
-  exit! 0
-end
-
 def package_config pkg, options={}
   # use MakeMakefile#pkg_config, which uses the system utility `pkg-config`.
   package = pkg_config(pkg)
@@ -158,6 +75,61 @@ def package_config pkg, options={}
   [cflags, ldflags, libs]
 end
 
+def preserving_globals
+  values = [$arg_config, $CFLAGS, $CPPFLAGS, $LDFLAGS, $LIBPATH, $libs].map(&:dup)
+  yield
+ensure
+  $arg_config, $CFLAGS, $CPPFLAGS, $LDFLAGS, $LIBPATH, $libs = values
+end
+
+def abort_could_not_find_library(lib)
+  abort "-----\n#{lib} is missing.  Please locate mkmf.log to investigate how it is failing.\n-----"
+end
+
+def chdir_for_build
+  # When using rake-compiler-dock on Windows, the underlying Virtualbox shared
+  # folders don't support symlinks, but libiconv expects it for a build on
+  # Linux. We work around this limitation by using the temp dir for cooking.
+  build_dir = ENV['RCD_HOST_RUBY_PLATFORM'].to_s =~ /mingw|mswin|cygwin/ ? '/tmp' : '.'
+  Dir.chdir(build_dir) do
+    yield
+  end
+end
+
+def sh_export_path path
+  # because libxslt 1.1.29 configure.in uses AC_PATH_TOOL which treats ":"
+  # as a $PATH separator, we need to convert windows paths from
+  #
+  #   C:/path/to/foo
+  #
+  # to
+  #
+  #   /C/path/to/foo
+  #
+  # which is sh-compatible, in order to find things properly during
+  # configuration
+  return path if !windows?
+
+  match = Regexp.new("^([A-Z]):(/.*)").match(path)
+  if match && match.length == 3
+    return File.join("/", match[1], match[2])
+  end
+
+  path
+end
+
+def libflag_to_filename(ldflag)
+  case ldflag
+  when /\A-l(.+)/
+    "lib#{$1}.#{$LIBEXT}"
+  end
+end
+
+def using_system_libraries?
+  # NOTE: TruffleRuby uses this env var as it does not support using static libraries yet.
+  arg_config('--use-system-libraries', !!ENV['NOKOGIRI_USE_SYSTEM_LIBRARIES'])
+end
+
 def have_libxml_headers?(version=nil)
   source = if version.nil?
              <<~SRC
@@ -176,18 +148,7 @@ def have_libxml_headers?(version=nil)
   try_cpp source
 end
 
-def preserving_globals
-  values = [$arg_config, $CFLAGS, $CPPFLAGS, $LDFLAGS, $LIBPATH, $libs].map(&:dup)
-  yield
-ensure
-  $arg_config, $CFLAGS, $CPPFLAGS, $LDFLAGS, $LIBPATH, $libs = values
-end
-
-def abort_could_not_find_library(lib)
-  abort "-----\n#{lib} is missing.  Please locate mkmf.log to investigate how it is failing.\n-----"
-end
-
-def have_iconv?(using = nil)
+def try_link_iconv(using = nil)
   checking_for(using ? "iconv using #{using}" : 'iconv') do
     ['', '-liconv'].any? do |opt|
       preserving_globals do
@@ -212,7 +173,7 @@ def iconv_configure_flags
   # give --with-iconv-dir and --with-opt-dir first priority
   ["iconv", "opt"].each do |target|
     config = preserving_globals { dir_config(target) }
-    if config.any? && have_iconv?("--with-#{target}-* flags") { dir_config(target) }
+    if config.any? && try_link_iconv("--with-#{target}-* flags") { dir_config(target) }
       idirs, ldirs = config.map do |dirs|
         Array(dirs).flat_map do |dir|
           dir.split(File::PATH_SEPARATOR)
@@ -227,12 +188,12 @@ def iconv_configure_flags
     end
   end
 
-  if have_iconv?
+  if try_link_iconv
     return ['--with-iconv=yes']
   end
 
   config = preserving_globals { package_config('libiconv') }
-  if config && have_iconv?('pkg-config libiconv') { package_config('libiconv') }
+  if config && try_link_iconv('pkg-config libiconv') { package_config('libiconv') }
     cflags, ldflags, libs = config
 
     return [
@@ -246,16 +207,6 @@ def iconv_configure_flags
   abort_could_not_find_library "libiconv"
 end
 
-def chdir_for_build
-  # When using rake-compiler-dock on Windows, the underlying Virtualbox shared
-  # folders don't support symlinks, but libiconv expects it for a build on
-  # Linux. We work around this limitation by using the temp dir for cooking.
-  build_dir = ENV['RCD_HOST_RUBY_PLATFORM'].to_s =~ /mingw|mswin|cygwin/ ? '/tmp' : '.'
-  Dir.chdir(build_dir) do
-    yield
-  end
-end
-
 def process_recipe(name, version, static_p, cross_p)
   MiniPortile.new(name, version).tap do |recipe|
     recipe.target = File.join(PACKAGE_ROOT_DIR, "ports")
@@ -356,16 +307,65 @@ def process_recipe(name, version, static_p, cross_p)
   end
 end
 
-def libflag_to_filename(ldflag)
-  case ldflag
-  when /\A-l(.+)/
-    "lib#{$1}.#{$LIBEXT}"
-  end
+def do_help
+  print <<~HELP
+    usage: ruby #{$0} [options]
+
+        --disable-clean
+            Do not clean out intermediate files after successful build.
+
+        --disable-static
+            Do not statically link bundled libraries.
+
+        --with-iconv-dir=DIR
+            Use the iconv library placed under DIR.
+
+        --with-zlib-dir=DIR
+            Use the zlib library placed under DIR.
+
+        --use-system-libraries
+            Use system libraries instead of building and using the bundled
+            libraries.
+
+        --with-xml2-dir=DIR / --with-xml2-config=CONFIG
+        --with-xslt-dir=DIR / --with-xslt-config=CONFIG
+        --with-exslt-dir=DIR / --with-exslt-config=CONFIG
+            Use libxml2/libxslt/libexslt as specified.
+
+        --enable-cross-build
+            Do cross-build.
+  HELP
+  exit! 0
 end
 
-def using_system_libraries?
-  # NOTE: TruffleRuby uses this env var as it does not support using static libraries yet.
-  arg_config('--use-system-libraries', !!ENV['NOKOGIRI_USE_SYSTEM_LIBRARIES'])
+def do_clean
+  require 'pathname'
+  require 'fileutils'
+
+  root = Pathname(PACKAGE_ROOT_DIR)
+  pwd  = Pathname(Dir.pwd)
+
+  # Skip if this is a development work tree
+  unless (root + '.git').exist?
+    message "Cleaning files only used during build.\n"
+
+    # (root + 'tmp') cannot be removed at this stage because
+    # nokogiri.so is yet to be copied to lib.
+
+    # clean the ports build directory
+    Pathname.glob(pwd.join('tmp', '*', 'ports')) do |dir|
+      FileUtils.rm_rf(dir, verbose: true)
+    end
+
+    if enable_config('static')
+      # ports installation can be safely removed if statically linked.
+      FileUtils.rm_rf(root + 'ports', verbose: true)
+    else
+      FileUtils.rm_rf(root + 'ports' + 'archives', verbose: true)
+    end
+  end
+
+  exit! 0
 end
 
 #
@@ -389,6 +389,7 @@ def using_system_libraries?
 # use same c compiler for libxml and libxslt
 ENV['CC'] = RbConfig::CONFIG['CC']
 
+# adopt environment config
 append_cflags(ENV["CFLAGS"].split(/\s+/)) if !ENV["CFLAGS"].nil?
 append_cppflags(ENV["CPPFLAGS"].split(/\s+/)) if !ENV["CPPFLAGS"].nil?
 append_ldflags(ENV["LDFLAGS"].split(/\s+/)) if !ENV["LDFLAGS"].nil?
@@ -397,15 +398,16 @@ def using_system_libraries?
 append_cflags("-g") # always include debugging information
 append_cflags("-Winline") # we use at least one inline function in the C extension
 append_cflags("-Wmissing-noreturn") # good to have no matter what Ruby was compiled with
-# append_cflags(["-Wcast-qual", "-Wwrite-strings"]) # these tend to be noisy, but on occasion useful during development
 append_cflags("-Wno-error=unused-command-line-argument-hard-error-in-future") if darwin?
+# append_cflags(["-Wcast-qual", "-Wwrite-strings"]) # these tend to be noisy, but on occasion useful during development
+
 append_cppflags("-DXP_UNIX") if nix?
 append_cppflags(["-DXP_WIN", "-DXP_WIN32"]) if windows?
 
 # Add SDK-specific include path for macOS and brew versions before v2.2.12 (2020-04-08) [#1851, #1801]
 macos_mojave_sdk_include_path = "/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/libxml2"
 if using_system_libraries? && darwin? && Dir.exist?(macos_mojave_sdk_include_path)
-  append_cppflags "-I #{macos_mojave_sdk_include_path}"
+  append_cppflags("-I #{macos_mojave_sdk_include_path}")
 end
 
 # Work around a character escaping bug in MSYS by passing an arbitrary
@@ -431,21 +433,19 @@ def using_system_libraries?
 else
   message "Building nokogiri using packaged libraries.\n"
 
+  static_p = enable_config('static', true) or message "Static linking is disabled.\n"
+  cross_build_p = enable_config("cross-build")
+
   require 'rubygems'
   gem 'mini_portile2', REQUIRED_MINI_PORTILE_VERSION
   require 'mini_portile2'
   message "Using mini_portile version #{MiniPortile::VERSION}\n"
 
   require 'yaml'
-
-  static_p = enable_config('static', true) or
-    message "Static linking is disabled.\n"
+  dependencies = YAML.load_file(File.join(PACKAGE_ROOT_DIR, "dependencies.yml"))
 
   dir_config('zlib')
 
-  dependencies = YAML.load_file(File.join(PACKAGE_ROOT_DIR, "dependencies.yml"))
-
-  cross_build_p = enable_config("cross-build")
   if cross_build_p || windows?
     zlib_recipe = process_recipe("zlib", dependencies["zlib"]["version"], static_p, cross_build_p) do |recipe|
       recipe.files = [{

From a95f0ebb3814ade579abd8e0d26558b88d66bb61 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Tue, 20 Oct 2020 13:54:22 -0400
Subject: [PATCH 21/33] cleanup(extconf): remove phantom preprocessor macros

these date back to 2009, were hardly ever used, and aren't used at all now
---
 ext/nokogiri/extconf.rb | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index 199fce9a3e..ce25b253f2 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -401,9 +401,6 @@ def do_clean
 append_cflags("-Wno-error=unused-command-line-argument-hard-error-in-future") if darwin?
 # append_cflags(["-Wcast-qual", "-Wwrite-strings"]) # these tend to be noisy, but on occasion useful during development
 
-append_cppflags("-DXP_UNIX") if nix?
-append_cppflags(["-DXP_WIN", "-DXP_WIN32"]) if windows?
-
 # Add SDK-specific include path for macOS and brew versions before v2.2.12 (2020-04-08) [#1851, #1801]
 macos_mojave_sdk_include_path = "/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/libxml2"
 if using_system_libraries? && darwin? && Dir.exist?(macos_mojave_sdk_include_path)

From afa2e803b0ee7b9fef4e09ed6699a3217db90106 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Wed, 21 Oct 2020 17:13:59 -0400
Subject: [PATCH 22/33] cleanup(extconf): move mini_portile require into
 process_recipe

---
 ext/nokogiri/extconf.rb | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index ce25b253f2..31d6f248f8 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -208,6 +208,11 @@ def iconv_configure_flags
 end
 
 def process_recipe(name, version, static_p, cross_p)
+  require 'rubygems'
+  gem 'mini_portile2', REQUIRED_MINI_PORTILE_VERSION
+  require 'mini_portile2'
+  message "Using mini_portile version #{MiniPortile::VERSION}\n"
+
   MiniPortile.new(name, version).tap do |recipe|
     recipe.target = File.join(PACKAGE_ROOT_DIR, "ports")
     # Prefer host_alias over host in order to use i586-mingw32msvc as
@@ -433,11 +438,6 @@ def do_clean
   static_p = enable_config('static', true) or message "Static linking is disabled.\n"
   cross_build_p = enable_config("cross-build")
 
-  require 'rubygems'
-  gem 'mini_portile2', REQUIRED_MINI_PORTILE_VERSION
-  require 'mini_portile2'
-  message "Using mini_portile version #{MiniPortile::VERSION}\n"
-
   require 'yaml'
   dependencies = YAML.load_file(File.join(PACKAGE_ROOT_DIR, "dependencies.yml"))
 

From 4645abb4b91da0c2ed8793add37bdbd99d8304dd Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Wed, 21 Oct 2020 17:15:48 -0400
Subject: [PATCH 23/33] cleanup(rake): indent heredocs with `<<~`

---
 tasks/cross-ruby.rb | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/tasks/cross-ruby.rb b/tasks/cross-ruby.rb
index 27a1599536..cdf444b029 100644
--- a/tasks/cross-ruby.rb
+++ b/tasks/cross-ruby.rb
@@ -238,7 +238,7 @@ def verify_dll(dll, cross_ruby)
     desc "build native gem for #{plat} platform (host)"
     task plat do
       # TODO remove `find` after https://github.com/rake-compiler/rake-compiler/pull/171 is shipped
-      RakeCompilerDock.sh <<-EOT, platform: plat
+      RakeCompilerDock.sh <<~EOT, platform: plat
         gem install bundler --no-document &&
         bundle &&
         find /usr/local/rvm/gems -name extensiontask.rb | while read f ; do sudo sed -i 's/callback.call(spec) if callback/@cross_compiling.call(spec) if @cross_compiling/' $f ; done &&
@@ -330,10 +330,10 @@ def verify_dll(dll, cross_ruby)
     ext.cross_config_options << "--enable-cross-build"
     ext.cross_compiling do |spec|
       libs = dependencies.map { |name, dep| "#{name}-#{dep["version"]}" }.join(', ')
-
-      spec.post_install_message = <<-EOS
-Nokogiri is built with the packaged libraries: #{libs}.
+      spec.post_install_message = <<~EOS
+        Nokogiri is built with the packaged libraries: #{libs}.
       EOS
+
       spec.files.reject! { |path| File.fnmatch?('ports/*', path) }
       spec.dependencies.reject! { |dep| dep.name=='mini_portile2' }
     end

From fd2ffbaebb55163a3f0b1e4171ec04f201d69b30 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 26 Oct 2020 07:40:09 -0400
Subject: [PATCH 24/33] cleanup(dev): explicit requires

---
 Rakefile                | 5 -----
 ext/nokogiri/extconf.rb | 9 +++++----
 tasks/cross-ruby.rb     | 3 +++
 3 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/Rakefile b/Rakefile
index 577c684900..8125faf0a3 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,4 +1,3 @@
-# -*- ruby -*-
 require 'hoe'
 
 Hoe.plugin :bundler
@@ -7,8 +6,6 @@ Hoe.plugin :gemspec
 Hoe.plugin :git
 Hoe.plugin :markdown
 
-require 'shellwords'
-
 require_relative "tasks/util"
 
 HOE = Hoe.spec 'nokogiri' do
@@ -85,5 +82,3 @@ require_relative "tasks/set-version-to-timestamp"
 # work around Hoe's inflexibility about the default tasks
 Rake::Task[:default].prerequisites.unshift("compile")
 Rake::Task[:default].prerequisites.unshift("rubocop")
-
-# vim: syntax=Ruby
diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index 31d6f248f8..2ac4ce2c29 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -1,7 +1,11 @@
 # :stopdoc:
 ENV['RC_ARCHS'] = '' if RUBY_PLATFORM =~ /darwin/
 
-require 'mkmf'
+require "mkmf"
+require "rbconfig"
+require "fileutils"
+require "shellwords"
+require "pathname"
 
 #
 #  helpful constants
@@ -344,9 +348,6 @@ def do_help
 end
 
 def do_clean
-  require 'pathname'
-  require 'fileutils'
-
   root = Pathname(PACKAGE_ROOT_DIR)
   pwd  = Pathname(Dir.pwd)
 
diff --git a/tasks/cross-ruby.rb b/tasks/cross-ruby.rb
index cdf444b029..a40c482783 100644
--- a/tasks/cross-ruby.rb
+++ b/tasks/cross-ruby.rb
@@ -1,3 +1,6 @@
+require "rbconfig"
+require "shellwords"
+
 CrossRuby = Struct.new(:version, :host) do
   WINDOWS_PLATFORM_REGEX = /mingw|mswin/
   MINGW32_PLATFORM_REGEX = /mingw32/

From 5f05028f03495e8f040dcb9770dfd5d02881716d Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 26 Oct 2020 08:01:05 -0400
Subject: [PATCH 25/33] cleanup(dev): groom the Rakefile

---
 Rakefile | 52 ++++++++++++++++++++++++++++------------------------
 1 file changed, 28 insertions(+), 24 deletions(-)

diff --git a/Rakefile b/Rakefile
index 8125faf0a3..67f3e898b0 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,4 +1,4 @@
-require 'hoe'
+require "hoe"
 
 Hoe.plugin :bundler
 Hoe.plugin :debugging
@@ -8,18 +8,22 @@ Hoe.plugin :markdown
 
 require_relative "tasks/util"
 
-HOE = Hoe.spec 'nokogiri' do
-  developer 'Aaron Patterson', 'aaronp@rubyforge.org'
-  developer 'Mike Dalessio',   'mike.dalessio@gmail.com'
-  developer 'Yoko Harada',     'yokolet@gmail.com'
-  developer 'Tim Elliott',     'tle@holymonkey.com'
-  developer 'Akinori MUSHA',   'knu@idaemons.org'
-  developer 'John Shahid',     'jvshahid@gmail.com'
-  developer 'Lars Kanis',      'lars@greiz-reinsdorf.de'
+HOE = Hoe.spec "nokogiri" do |hoe|
+  hoe.author = [
+    "Mike Dalessio",
+    "Aaron Patterson",
+    "John Shahid",
+    "Yoko Harada",
+    "Akinori MUSHA",
+    "Lars Kanis",
+    "Tim Elliott",
+  ]
+
+  hoe.email = "nokogiri-talk@googlegroups.com"
 
-  license "MIT"
+  hoe.license "MIT"
 
-  self.urls = {
+  hoe.urls = {
     "home" => "https://nokogiri.org",
     "bugs" => "https://github.com/sparklemotion/nokogiri/issues",
     "doco" => "https://nokogiri.org/rdoc/index.html",
@@ -27,23 +31,23 @@ HOE = Hoe.spec 'nokogiri' do
     "code" => "https://github.com/sparklemotion/nokogiri",
   }
 
-  self.markdown_linkify_files = FileList["*.md"]
-  self.extra_rdoc_files = FileList['ext/nokogiri/*.c']
+  hoe.markdown_linkify_files = FileList["*.md"]
+  hoe.extra_rdoc_files = FileList["ext/nokogiri/*.c"]
 
-  self.clean_globs += [
-    'nokogiri.gemspec',
-    'lib/nokogiri/nokogiri.{bundle,jar,rb,so}',
-    'lib/nokogiri/[0-9].[0-9]',
+  hoe.clean_globs += [
+    "nokogiri.gemspec",
+    "lib/nokogiri/nokogiri.{bundle,jar,rb,so}",
+    "lib/nokogiri/[0-9].[0-9]",
   ]
-  self.clean_globs += Dir.glob("ports/*").reject { |d| d =~ %r{/archives$} }
+  hoe.clean_globs += Dir.glob("ports/*").reject { |d| d =~ %r{/archives$} }
 
   unless java?
-    self.extra_deps += [
+    hoe.extra_deps += [
       ["mini_portile2", "~> 2.5.0"], # keep version in sync with extconf.rb
     ]
   end
 
-  self.extra_dev_deps += [
+  hoe.extra_dev_deps += [
     ["concourse", "~> 0.38"],
     ["hoe", ["~> 3.22", ">= 3.22.1"]],
     ["hoe-bundler", "~> 1.2"],
@@ -61,13 +65,13 @@ HOE = Hoe.spec 'nokogiri' do
     ["simplecov", "~> 0.17.0"], # locked due to https://github.com/codeclimate/test-reporter/issues/413
   ]
 
-  self.spec_extras = {
+  hoe.spec_extras = {
     :extensions => ["ext/nokogiri/extconf.rb"],
-    :required_ruby_version => '>= 2.4.0'
+    :required_ruby_version => ">= 2.4.0"
   }
 
-  self.testlib = :minitest
-  self.test_prelude = 'require "helper"' # ensure simplecov gets loaded before anything else
+  hoe.testlib = :minitest
+  hoe.test_prelude = %q(require "helper") # ensure simplecov gets loaded before anything else
 end
 
 require_relative "tasks/cross-ruby"

From 28f12039d5504d599471169c8512a8d2b9d23391 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 26 Oct 2020 08:01:46 -0400
Subject: [PATCH 26/33] dev: Remove old markdown tasks, which were replaced by
 hoe-markdown

(This should have been done as part of ec4cf38.)
---
 Rakefile              |  1 -
 tasks/docs-linkify.rb | 53 -------------------------------------------
 2 files changed, 54 deletions(-)
 delete mode 100644 tasks/docs-linkify.rb

diff --git a/Rakefile b/Rakefile
index 67f3e898b0..c0c2946504 100644
--- a/Rakefile
+++ b/Rakefile
@@ -79,7 +79,6 @@ require_relative "tasks/concourse"
 require_relative "tasks/css-generate"
 require_relative "tasks/debug"
 require_relative "tasks/docker"
-require_relative "tasks/docs-linkify"
 require_relative "tasks/rubocop"
 require_relative "tasks/set-version-to-timestamp"
 
diff --git a/tasks/docs-linkify.rb b/tasks/docs-linkify.rb
deleted file mode 100644
index 200eeed5b6..0000000000
--- a/tasks/docs-linkify.rb
+++ /dev/null
@@ -1,53 +0,0 @@
-linkify_tasks = []
-
-namespace "docs:linkify" do
-  CHANGELOG_PATH = File.expand_path(File.join(File.dirname(__FILE__), "..", HOE.history_file))
-  ROADMAP_PATH = File.expand_path(File.join(File.dirname(__FILE__), "..", "ROADMAP.md"))
-
-  [CHANGELOG_PATH, ROADMAP_PATH].each do |docfile_path|
-    docfile_name = File.basename(docfile_path)
-    taskname = docfile_name.downcase.split(".").first
-
-    # this task is idempotent
-    desc "link issues and usernames in #{docfile_name}"
-    task taskname do
-      puts "linkifying #{docfile_path} ..."
-      docs = File.read(docfile_path)
-
-      github_issue_regex = /
-        \#([[:digit:]]+)  # issue number, like '#1234'
-        (?!\]\()          # not already in a markdown hyperlink
-        (?![[[:digit:]]]) # don't truncate the issue number to meet the previous negative lookahead
-      /x
-      docs.gsub!(github_issue_regex, "[#\\1](#{HOE.urls["bugs"]}/\\1)")
-
-      github_link_regex = %r{
-        (?<!\]\()          # not already in a markdown hyperlink
-        #{HOE.urls["bugs"]}/([[:digit:]]+)
-        (?![[[:digit:]]]) # don't truncate the issue number to meet the previous negative lookahead
-      }x
-      docs.gsub!(github_link_regex, "[#\\1](#{HOE.urls["bugs"]}/\\1)")
-
-      github_link_regex = %r{
-        (?<!\]\()          # not already in a markdown hyperlink
-        #{HOE.urls["bugs"].gsub("issues", "pull")}/([[:digit:]]+)
-        (?![[[:digit:]]]) # don't truncate the issue number to meet the previous negative lookahead
-      }x
-      docs.gsub!(github_link_regex, "[PR#\\1](#{HOE.urls["bugs"]}/\\1)")
-
-      # see https://github.com/shinnn/github-username-regex
-      github_user_regex = /
-        @([[:alnum:]](?:[[:alnum:]]|-(?=[[:alnum:]])){0,38}) # username, like "@flavorjones"
-        (?!\]\()                                             # not already in a markdown hyperlink
-        (?![[[:alnum:]]]) # don't truncate the username to meet the previous negative lookahead
-      /x
-      docs.gsub!(github_user_regex, "[@\\1](https://github.com/\\1)")
-
-      File.open(docfile_path, "w") { |f| f.write docs }
-    end
-    linkify_tasks << "docs:linkify:#{taskname}"
-  end
-end
-
-desc "link issues and usernames in doc files"
-task "docs:linkify" => linkify_tasks

From 9095706c14f7511b35cdca362005472fd4ccf552 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 26 Oct 2020 08:25:24 -0400
Subject: [PATCH 27/33] cleanup(dev): move rake tasks into /rakelib

---
 .hoerc                                                 |  3 ++-
 Rakefile                                               | 10 +---------
 tasks/concourse.rb => rakelib/concourse.rake           |  0
 tasks/cross-ruby.rb => rakelib/cross-ruby.rake         |  0
 tasks/css-generate.rb => rakelib/css-generate.rake     |  0
 tasks/debug.rb => rakelib/debug.rake                   |  0
 tasks/docker.rb => rakelib/docker.rake                 |  0
 tasks/rubocop.rb => rakelib/rubocop.rake               |  0
 .../set-version-to-timestamp.rake                      |  0
 {tasks => rakelib}/util.rb                             |  0
 10 files changed, 3 insertions(+), 10 deletions(-)
 rename tasks/concourse.rb => rakelib/concourse.rake (100%)
 rename tasks/cross-ruby.rb => rakelib/cross-ruby.rake (100%)
 rename tasks/css-generate.rb => rakelib/css-generate.rake (100%)
 rename tasks/debug.rb => rakelib/debug.rake (100%)
 rename tasks/docker.rb => rakelib/docker.rake (100%)
 rename tasks/rubocop.rb => rakelib/rubocop.rake (100%)
 rename tasks/set-version-to-timestamp.rb => rakelib/set-version-to-timestamp.rake (100%)
 rename {tasks => rakelib}/util.rb (100%)

diff --git a/.hoerc b/.hoerc
index 913d1b035b..54c813cf5f 100644
--- a/.hoerc
+++ b/.hoerc
@@ -4,12 +4,13 @@
 exclude: !ruby/regexp '/
 (^\.\/
   ((\.git
+    |.vagrant
     |.yardoc
     |concourse
     |gems
     |ports
     |suppressions
-    |tasks
+    |rakelib
     |test
     |tmp
   )\/)
diff --git a/Rakefile b/Rakefile
index c0c2946504..2323ee15cf 100644
--- a/Rakefile
+++ b/Rakefile
@@ -6,7 +6,7 @@ Hoe.plugin :gemspec
 Hoe.plugin :git
 Hoe.plugin :markdown
 
-require_relative "tasks/util"
+require_relative "rakelib/util"
 
 HOE = Hoe.spec "nokogiri" do |hoe|
   hoe.author = [
@@ -74,14 +74,6 @@ HOE = Hoe.spec "nokogiri" do |hoe|
   hoe.test_prelude = %q(require "helper") # ensure simplecov gets loaded before anything else
 end
 
-require_relative "tasks/cross-ruby"
-require_relative "tasks/concourse"
-require_relative "tasks/css-generate"
-require_relative "tasks/debug"
-require_relative "tasks/docker"
-require_relative "tasks/rubocop"
-require_relative "tasks/set-version-to-timestamp"
-
 # work around Hoe's inflexibility about the default tasks
 Rake::Task[:default].prerequisites.unshift("compile")
 Rake::Task[:default].prerequisites.unshift("rubocop")
diff --git a/tasks/concourse.rb b/rakelib/concourse.rake
similarity index 100%
rename from tasks/concourse.rb
rename to rakelib/concourse.rake
diff --git a/tasks/cross-ruby.rb b/rakelib/cross-ruby.rake
similarity index 100%
rename from tasks/cross-ruby.rb
rename to rakelib/cross-ruby.rake
diff --git a/tasks/css-generate.rb b/rakelib/css-generate.rake
similarity index 100%
rename from tasks/css-generate.rb
rename to rakelib/css-generate.rake
diff --git a/tasks/debug.rb b/rakelib/debug.rake
similarity index 100%
rename from tasks/debug.rb
rename to rakelib/debug.rake
diff --git a/tasks/docker.rb b/rakelib/docker.rake
similarity index 100%
rename from tasks/docker.rb
rename to rakelib/docker.rake
diff --git a/tasks/rubocop.rb b/rakelib/rubocop.rake
similarity index 100%
rename from tasks/rubocop.rb
rename to rakelib/rubocop.rake
diff --git a/tasks/set-version-to-timestamp.rb b/rakelib/set-version-to-timestamp.rake
similarity index 100%
rename from tasks/set-version-to-timestamp.rb
rename to rakelib/set-version-to-timestamp.rake
diff --git a/tasks/util.rb b/rakelib/util.rb
similarity index 100%
rename from tasks/util.rb
rename to rakelib/util.rb

From fe314f82daa5eb507e88619c2986b87d5525850f Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 26 Oct 2020 10:36:40 -0400
Subject: [PATCH 28/33] cleanup(extconf): CFLAGS handling in recipes

---
 ext/nokogiri/extconf.rb | 42 ++++++++++++++++++++++++++++++++---------
 1 file changed, 33 insertions(+), 9 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index 2ac4ce2c29..a0dc31801c 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -248,7 +248,7 @@ def process_recipe(name, version, static_p, cross_p)
         "--disable-shared",
         "--enable-static",
       ]
-      env['CFLAGS'] = "-fPIC #{env['CFLAGS']}"
+      env["CFLAGS"] = [env["CFLAGS"], "-fPIC"].join(" ")
     else
       recipe.configure_options += [
         "--enable-shared",
@@ -485,7 +485,8 @@ def install
       else
         class << recipe
           def configure
-            execute "configure", ["env", "CHOST=#{host}", "CFLAGS=-fPIC #{ENV['CFLAGS']}", "./configure", "--static", configure_prefix]
+            cflags = [ENV["CFLAGS"], "-fPIC", "-g"].join(" ")
+            execute "configure", ["env", "CHOST=#{host}", "CFLAGS=#{cflags}", "./configure", "--static", configure_prefix]
           end
         end
       end
@@ -497,10 +498,13 @@ def configure
             url: "http://ftp.gnu.org/pub/gnu/libiconv/#{recipe.name}-#{recipe.version}.tar.gz",
             sha256: dependencies["libiconv"]["sha256"]
           }]
+
+        cflags = [ENV["CFLAGS"], "-O2", "-g"].join(" ")
+
         recipe.configure_options += [
           "CPPFLAGS=-Wall",
-          "CFLAGS=-O2 -g",
-          "CXXFLAGS=-O2 -g",
+          "CFLAGS=#{cflags}",
+          "CXXFLAGS=#{cflags}",
           "LDFLAGS="
         ]
       end
@@ -532,15 +536,31 @@ def configure
         url: "http://xmlsoft.org/sources/#{recipe.name}-#{recipe.version}.tar.gz",
         sha256: dependencies["libxml2"]["sha256"]
       }]
+
+    cflags = ENV["CFLAGS"]
+
+    if zlib_recipe
+      recipe.configure_options << "--with-zlib=#{zlib_recipe.path}"
+      cflags = [cflags, "-I#{zlib_recipe.path}/include"].join(" ")
+    end
+
+    if libiconv_recipe
+      recipe.configure_options << "--with-iconv=#{libiconv_recipe.path}"
+    else
+      recipe.configure_options << iconv_configure_flags
+    end
+
+    if darwin?
+      recipe.configure_options += ["RANLIB=/usr/bin/ranlib", "AR=/usr/bin/ar"]
+    end
+
     recipe.configure_options += [
       "--without-python",
       "--without-readline",
-      *(zlib_recipe ? ["--with-zlib=#{zlib_recipe.path}", "CFLAGS=-I#{zlib_recipe.path}/include"] : []),
-      *(libiconv_recipe ? "--with-iconv=#{libiconv_recipe.path}" : iconv_configure_flags),
       "--with-c14n",
       "--with-debug",
       "--with-threads",
-      *(darwin? ? ["RANLIB=/usr/bin/ranlib", "AR=/usr/bin/ar"] : "")
+      "CFLAGS=#{cflags}"
     ]
   end
 
@@ -549,16 +569,20 @@ def configure
         url: "http://xmlsoft.org/sources/#{recipe.name}-#{recipe.version}.tar.gz",
         sha256: dependencies["libxslt"]["sha256"]
       }]
+
+    if darwin?
+      recipe.configure_options += ["RANLIB=/usr/bin/ranlib", "AR=/usr/bin/ar"]
+    end
+
     recipe.configure_options += [
       "--without-python",
       "--without-crypto",
       "--with-debug",
       "--with-libxml-prefix=#{sh_export_path(libxml2_recipe.path)}",
-      *(darwin? ? ["RANLIB=/usr/bin/ranlib", "AR=/usr/bin/ar"] : "")
     ]
   end
 
-  $CFLAGS << ' ' << '-DNOKOGIRI_USE_PACKAGED_LIBRARIES'
+  $CFLAGS = [$CFLAGS, "-DNOKOGIRI_USE_PACKAGED_LIBRARIES"].join(" ")
   $LIBPATH = ["#{zlib_recipe.path}/lib"] | $LIBPATH if zlib_recipe
   $LIBPATH = ["#{libiconv_recipe.path}/lib"] | $LIBPATH if libiconv_recipe
 

From 511828967882183fa8b119f424be2de22ae5e581 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 26 Oct 2020 13:21:40 -0400
Subject: [PATCH 29/33] cleanup(extconf): configuration parameter handling

- extract helper concat_flags
- strip spaces from configuration params
---
 ext/nokogiri/extconf.rb | 22 +++++++++++++---------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index a0dc31801c..26d62f1196 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -45,6 +45,10 @@ def nix?
   ! (windows? || solaris? || darwin?)
 end
 
+def concat_flags *args
+  args.compact.join(" ")
+end
+
 def package_config pkg, options={}
   # use MakeMakefile#pkg_config, which uses the system utility `pkg-config`.
   package = pkg_config(pkg)
@@ -248,7 +252,7 @@ def process_recipe(name, version, static_p, cross_p)
         "--disable-shared",
         "--enable-static",
       ]
-      env["CFLAGS"] = [env["CFLAGS"], "-fPIC"].join(" ")
+      env["CFLAGS"] = concat_flags(env["CFLAGS"], "-fPIC")
     else
       recipe.configure_options += [
         "--enable-shared",
@@ -266,13 +270,13 @@ def process_recipe(name, version, static_p, cross_p)
     if RbConfig::CONFIG['target_cpu'] == 'universal'
       %w[CFLAGS LDFLAGS].each do |key|
         unless env[key].include?('-arch')
-          env[key] += ' ' + RbConfig::CONFIG['ARCH_FLAG']
+          env[key] = concat_flags(env[key], RbConfig::CONFIG['ARCH_FLAG'])
         end
       end
     end
 
     recipe.configure_options += env.map do |key, value|
-      "#{key}=#{value}"
+      "#{key}=#{value.strip}"
     end
 
     message <<~EOM
@@ -399,7 +403,7 @@ def do_clean
 append_cflags(ENV["CFLAGS"].split(/\s+/)) if !ENV["CFLAGS"].nil?
 append_cppflags(ENV["CPPFLAGS"].split(/\s+/)) if !ENV["CPPFLAGS"].nil?
 append_ldflags(ENV["LDFLAGS"].split(/\s+/)) if !ENV["LDFLAGS"].nil?
-$LIBS << " #{ENV["LIBS"]}"
+$LIBS = concat_flags($LIBS, ENV["LIBS"])
 
 append_cflags("-g") # always include debugging information
 append_cflags("-Winline") # we use at least one inline function in the C extension
@@ -485,7 +489,7 @@ def install
       else
         class << recipe
           def configure
-            cflags = [ENV["CFLAGS"], "-fPIC", "-g"].join(" ")
+            cflags = concat_flags(ENV["CFLAGS"], "-fPIC", "-g")
             execute "configure", ["env", "CHOST=#{host}", "CFLAGS=#{cflags}", "./configure", "--static", configure_prefix]
           end
         end
@@ -541,13 +545,13 @@ def configure
 
     if zlib_recipe
       recipe.configure_options << "--with-zlib=#{zlib_recipe.path}"
-      cflags = [cflags, "-I#{zlib_recipe.path}/include"].join(" ")
+      cflags = concat_flags(cflags, "-I#{zlib_recipe.path}/include")
     end
 
     if libiconv_recipe
       recipe.configure_options << "--with-iconv=#{libiconv_recipe.path}"
     else
-      recipe.configure_options << iconv_configure_flags
+      recipe.configure_options += iconv_configure_flags
     end
 
     if darwin?
@@ -560,7 +564,7 @@ def configure
       "--with-c14n",
       "--with-debug",
       "--with-threads",
-      "CFLAGS=#{cflags}"
+      "CFLAGS=#{cflags}",
     ]
   end
 
@@ -582,7 +586,7 @@ def configure
     ]
   end
 
-  $CFLAGS = [$CFLAGS, "-DNOKOGIRI_USE_PACKAGED_LIBRARIES"].join(" ")
+  $CFLAGS = concat_flags($CFLAGS, "-DNOKOGIRI_USE_PACKAGED_LIBRARIES")
   $LIBPATH = ["#{zlib_recipe.path}/lib"] | $LIBPATH if zlib_recipe
   $LIBPATH = ["#{libiconv_recipe.path}/lib"] | $LIBPATH if libiconv_recipe
 

From a93cf67dc94bec64a9d3848f8968341fc05f054b Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 26 Oct 2020 13:22:29 -0400
Subject: [PATCH 30/33] cleanup(extconf): add configuration params to build
 output

and skip printing the big notice if the library is already build
---
 ext/nokogiri/extconf.rb | 45 ++++++++++++++++++++++-------------------
 1 file changed, 24 insertions(+), 21 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index 26d62f1196..d3f00d761d 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -279,38 +279,41 @@ def process_recipe(name, version, static_p, cross_p)
       "#{key}=#{value.strip}"
     end
 
-    message <<~EOM
-      ---------- IMPORTANT NOTICE ----------
-      Building Nokogiri with a packaged version of #{name}-#{version}#{'.' if recipe.patch_files.empty?}
-    EOM
+    checkpoint = "#{recipe.target}/#{recipe.name}-#{recipe.version}-#{recipe.host}.installed"
+    if File.exist?(checkpoint)
+      message "Building Nokogiri with a packaged version of #{name}-#{version}.\n"
+    else
+      message <<~EOM
+        ---------- IMPORTANT NOTICE ----------
+        Building Nokogiri with a packaged version of #{name}-#{version}.
+        Configuration options: #{recipe.configure_options.shelljoin}
+      EOM
 
-    unless recipe.patch_files.empty?
-      message "with the following patches applied:\n"
+      unless recipe.patch_files.empty?
+        message "The following patches are being applied:\n"
 
-      recipe.patch_files.each do |patch|
-        message "  - %s\n" % File.basename(patch)
+        recipe.patch_files.each do |patch|
+          message "  - %s\n" % File.basename(patch)
+        end
       end
-    end
 
-    message <<~EOM
+      message <<~EOM
 
-      The Nokogiri maintainers intend to provide timely security updates, but if
-      this is a concern for you and want to use your OS/distro system library
-      instead, then abort this installation process and install nokogiri as
-      instructed at:
+        The Nokogiri maintainers intend to provide timely security updates, but if
+        this is a concern for you and want to use your OS/distro system library
+        instead, then abort this installation process and install nokogiri as
+        instructed at:
 
           https://nokogiri.org/tutorials/installing_nokogiri.html#install-with-system-libraries
 
-    EOM
+      EOM
 
-    message <<~EOM if name == 'libxml2'
-      Note, however, that nokogiri cannot guarantee compatiblity with every
-      version of libxml2 that may be provided by OS/package vendors.
+      message <<~EOM if name == 'libxml2'
+        Note, however, that nokogiri cannot guarantee compatiblity with every
+        version of libxml2 that may be provided by OS/package vendors.
 
-    EOM
+      EOM
 
-    checkpoint = "#{recipe.target}/#{recipe.name}-#{recipe.version}-#{recipe.host}.installed"
-    unless File.exist?(checkpoint)
       chdir_for_build do
         recipe.cook
       end

From 4f5c4d6bf0d9545d1cd55c0aee07fcab68976329 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 26 Oct 2020 13:42:06 -0400
Subject: [PATCH 31/33] cleanup(extconf): ensure config variables don't get
 clobbered

if, for example, CFLAGS appeared multiple times then it would get
clobbered. this change appends all the values to a single set of flags.
---
 ext/nokogiri/extconf.rb | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index d3f00d761d..359a7491d6 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -240,7 +240,11 @@ def process_recipe(name, version, static_p, cross_p)
     recipe.configure_options.delete_if do |option|
       case option
       when /\A(\w+)=(.*)\z/
-        env[$1] = $2
+        if env.key?($1)
+          env[$1] = concat_flags(env[$1], $2)
+        else
+          env[$1] = $2
+        end
         true
       else
         false

From 0b49210cdfd2c1089b7af6fd91ff5399481303cd Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 26 Oct 2020 13:44:44 -0400
Subject: [PATCH 32/33] perf: Always compile libxml2 and libxslt with '-O2 -g'

This is the default for those libraries, but we were overriding CFLAGS
in some cases.

Additionally, we need to compile with -U_FORTIFY_SOURCE to avoid
Ubuntu's convention of setting -D_FORTIFY_SOURCE=2 when -O2 is
set. This leads to problems when running precompiled libraries on
musl (see #2100 for details).

Closes #2022.
---
 ext/nokogiri/extconf.rb | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/ext/nokogiri/extconf.rb b/ext/nokogiri/extconf.rb
index 359a7491d6..466b406f69 100644
--- a/ext/nokogiri/extconf.rb
+++ b/ext/nokogiri/extconf.rb
@@ -510,7 +510,7 @@ def configure
             sha256: dependencies["libiconv"]["sha256"]
           }]
 
-        cflags = [ENV["CFLAGS"], "-O2", "-g"].join(" ")
+        cflags = concat_flags(ENV["CFLAGS"], "-O2", "-U_FORTIFY_SOURCE", "-g")
 
         recipe.configure_options += [
           "CPPFLAGS=-Wall",
@@ -548,7 +548,7 @@ def configure
         sha256: dependencies["libxml2"]["sha256"]
       }]
 
-    cflags = ENV["CFLAGS"]
+    cflags = concat_flags(ENV["CFLAGS"], "-O2", "-U_FORTIFY_SOURCE", "-g")
 
     if zlib_recipe
       recipe.configure_options << "--with-zlib=#{zlib_recipe.path}"
@@ -581,6 +581,8 @@ def configure
         sha256: dependencies["libxslt"]["sha256"]
       }]
 
+    cflags = concat_flags(ENV["CFLAGS"], "-O2", "-U_FORTIFY_SOURCE", "-g")
+
     if darwin?
       recipe.configure_options += ["RANLIB=/usr/bin/ranlib", "AR=/usr/bin/ar"]
     end
@@ -590,6 +592,7 @@ def configure
       "--without-crypto",
       "--with-debug",
       "--with-libxml-prefix=#{sh_export_path(libxml2_recipe.path)}",
+      "CFLAGS=#{cflags}",
     ]
   end
 

From ed2aa3b65f24d2de5908417f37614fad4f9b8f60 Mon Sep 17 00:00:00 2001
From: Mike Dalessio <mike.dalessio@gmail.com>
Date: Mon, 26 Oct 2020 14:39:50 -0400
Subject: [PATCH 33/33] doc: update CHANGELOG

---
 CHANGELOG.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index c631eaf619..ac77fd9dc6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -88,6 +88,7 @@ This release ends support for:
 * Improve performance of some namespace operations. [[#1916](https://github.com/sparklemotion/nokogiri/issues/1916)] (Thanks, [@ashmaroli](https://github.com/ashmaroli)!)
 * Remove unnecessary array allocations from Node serialization methods [[#1911](https://github.com/sparklemotion/nokogiri/issues/1911)] (Thanks, [@ashmaroli](https://github.com/ashmaroli)!)
 * Avoid creation of unnecessary zero-length String objects. [[#1970](https://github.com/sparklemotion/nokogiri/issues/1970)] (Thanks, [@ashmaroli](https://github.com/ashmaroli)!)
+* Always compile libxml2 and libxslt with '-O2' [[#2022](https://github.com/sparklemotion/nokogiri/issues/2022), [#2100](https://github.com/sparklemotion/nokogiri/issues/2100)] (Thanks, [@ilyazub](https://github.com/ilyazub)!)
 * [JRuby] Lots of code cleanup and performance improvements. [[#1934](https://github.com/sparklemotion/nokogiri/issues/1934)] (Thanks, [@kares](https://github.com/kares)!)
 * [JRuby] Clean up deprecated calls into JRuby. [[#2027](https://github.com/sparklemotion/nokogiri/issues/2027)] (Thanks, [@headius](https://github.com/headius)!)