diff --git a/ext/re2/extconf.rb b/ext/re2/extconf.rb
index d3b53a4..3571c46 100644
--- a/ext/re2/extconf.rb
+++ b/ext/re2/extconf.rb
@@ -29,6 +29,13 @@
         --with-re2-dir=DIRECTORY
             Look for re2 headers and library in DIRECTORY.
 
+
+    Flags only used when building and using the packaged libraries:
+
+      --enable-cross-build
+          Enable cross-build mode. (You probably do not want to set this manually.)
+
+
     Environment variables used:
 
       CC
@@ -54,6 +61,10 @@ def config_system_libraries?
   enable_config("system-libraries", ENV.key?('RE2_USE_SYSTEM_LIBRARIES'))
 end
 
+def config_cross_build?
+  enable_config("cross-build")
+end
+
 def concat_flags(*args)
   args.compact.join(" ")
 end
@@ -82,6 +93,10 @@ def target_host
   host.gsub(/i386/, "i686")
 end
 
+def target_arch
+  RbConfig::CONFIG['arch']
+end
+
 def with_temp_dir
   Dir.mktmpdir do |temp_dir|
     Dir.chdir(temp_dir) do
@@ -203,9 +218,16 @@ def process_recipe(name, version)
   require "mini_portile2"
   message("Using mini_portile version #{MiniPortile::VERSION}\n")
 
+  cross_build_p = config_cross_build?
+  message "Cross build is #{cross_build_p ? "enabled" : "disabled"}.\n"
+
   MiniPortileCMake.new(name, version).tap do |recipe|
     recipe.host = target_host
-    recipe.target = File.join(PACKAGE_ROOT_DIR, "ports")
+    target_dir = File.join(PACKAGE_ROOT_DIR, "ports")
+    # Ensure x64-mingw-ucrt and x64-mingw32 use different library paths since the host
+    # is the same (x86_64-w64-mingw32).
+    target_dir = File.join(target_dir, target_arch) if cross_build_p
+    recipe.target = target_dir
 
     recipe.configure_options += [
       # abseil needs a C++14 compiler