Add mpir for windows gmp support

config/pkg/ext/builtin-extensions.yml

@@ -82,10 +82,13 @@ ext-gettext:
     arg-type: with-path
 ext-gmp:
   type: php-extension
-  depends:
+  depends@unix:
     - gmp
+  depends@windows:
+    - mpir
   php-extension:
     arg-type: with-path
+    arg-type@windows: with
 ext-iconv:
   type: php-extension
   depends@unix:

config/pkg/lib/mpir.yml

@@ -0,0 +1,9 @@
+mpir:
+  type: library
+  artifact:
+    source:
+      type: git
+      url: 'https://github.com/winlibs/mpir.git'
+      rev: master
+  static-libs@windows:
+    - mpir_a.lib