diff --git a/distrib/lib/win32-msvc2008/mpir.lib b/distrib/lib/win32-msvc2008/mpir.lib
deleted file mode 100644
index 7fd50fcfb..000000000
Binary files a/distrib/lib/win32-msvc2008/mpir.lib and /dev/null differ
diff --git a/distrib/lib/win32-msvc2008/mpirxx.lib b/distrib/lib/win32-msvc2008/mpirxx.lib
deleted file mode 100644
index 3fc22079c..000000000
Binary files a/distrib/lib/win32-msvc2008/mpirxx.lib and /dev/null differ
diff --git a/distrib/lib/win32-msvc2015/mpir.lib b/distrib/lib/win32-msvc2015/mpir.lib
deleted file mode 100644
index cd191c7ac..000000000
Binary files a/distrib/lib/win32-msvc2015/mpir.lib and /dev/null differ
diff --git a/distrib/lib/win32-msvc2015/mpirxx.lib b/distrib/lib/win32-msvc2015/mpirxx.lib
deleted file mode 100644
index 17f6d049a..000000000
Binary files a/distrib/lib/win32-msvc2015/mpirxx.lib and /dev/null differ
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index cef73c352..902751792 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -224,7 +224,8 @@ set(COPIED_FILES)
 file(
 	GLOB SHADERS
 	LIST_DIRECTORIES false
-	"${CMAKE_CURRENT_SOURCE_DIR}/../distrib/shaders/*.vert" "${CMAKE_CURRENT_SOURCE_DIR}/../distrib/shaders/*.frag"
+	"${CMAKE_CURRENT_SOURCE_DIR}/../distrib/shaders/*.vert"
+	"${CMAKE_CURRENT_SOURCE_DIR}/../distrib/shaders/*.frag"
 	"${CMAKE_CURRENT_SOURCE_DIR}/../distrib/shaders/*.gdp")
 foreach(FN ${SHADERS})
 	get_filename_component(NAME_ONLY ${FN} NAME)
diff --git a/src/external/external.cmake b/src/external/external.cmake
index 9226b4935..e329193c4 100644
--- a/src/external/external.cmake
+++ b/src/external/external.cmake
@@ -13,14 +13,8 @@ set(LIB3DS_DIR ${EXTERNAL_DIR}/lib3ds-1.3.0)
 add_subdirectory(${LIB3DS_DIR})
 
 # gmp or mpir - optional, for filter_csg
-if(GMP_FOUND)
-    message(STATUS "- GMP/MPIR - using system-provided GMP library")
-    add_library(external-gmp INTERFACE)
-    target_include_directories(external-gmp SYSTEM INTERFACE ${GMP_INCLUDE_DIRS})
-    target_link_libraries(external-gmp INTERFACE ${GMP_LIBRARIES})
-else()
-    # TODO set up external-mpir per-os for bundled mpir
-endif()
+set(MPIR_DIR ${EXTERNAL_DIR}/mpir)
+add_subdirectory(${MPIR_DIR})
 
 # muparser - optional, for filter_func
 set(MUPARSER_DIR ${EXTERNAL_DIR}/muparser_v225)
diff --git a/src/external/mpir/CMakeLists.txt b/src/external/mpir/CMakeLists.txt
new file mode 100644
index 000000000..c7934592d
--- /dev/null
+++ b/src/external/mpir/CMakeLists.txt
@@ -0,0 +1,18 @@
+if(GMP_FOUND)
+	message(STATUS "- GMP/MPIR - using system-provided GMP library")
+	add_library(external-gmp INTERFACE)
+	target_include_directories(external-gmp SYSTEM INTERFACE ${GMP_INCLUDE_DIRS})
+	target_link_libraries(external-gmp INTERFACE ${GMP_LIBRARIES})
+else()
+	if (WIN32 AND MSVC)
+		message(STATUS "- Using already built MPIR library.")
+		file(
+			COPY ${MPIR_DIR}/win32-msvc/mpir.lib ${MPIR_DIR}/win32-msvc/mpirxx.lib
+			DESTINATION ${MESHLAB_BUILD_DISTRIB_DIR})
+		add_library(mpir SHARED IMPORTED GLOBAL)
+		add_library(mpirxx SHARED IMPORTED GLOBAL)
+		target_include_directories(mpir INTERFACE ${EXTERNAL_DIR}/inc/win32-msvc/mpir-2.2.1_x64)
+		set_property(TARGET mpir PROPERTY IMPORTED_IMPLIB_RELEASE "${MESHLAB_BUILD_DISTRIB_DIR}/mpir.lib")
+		set_property(TARGET mpirxx PROPERTY IMPORTED_IMPLIB_RELEASE "${MESHLAB_BUILD_DISTRIB_DIR}/mpirxx.lib")
+	endif()
+endif()
diff --git a/distrib/lib/macx64/libmpir.a b/src/external/mpir/macx64/libmpir.a
similarity index 100%
rename from distrib/lib/macx64/libmpir.a
rename to src/external/mpir/macx64/libmpir.a
diff --git a/distrib/lib/macx64/libmpirxx.a b/src/external/mpir/macx64/libmpirxx.a
similarity index 100%
rename from distrib/lib/macx64/libmpirxx.a
rename to src/external/mpir/macx64/libmpirxx.a
diff --git a/distrib/lib/macx64/mpir.txt b/src/external/mpir/macx64/mpir.txt
similarity index 100%
rename from distrib/lib/macx64/mpir.txt
rename to src/external/mpir/macx64/mpir.txt
diff --git a/distrib/lib/readme.txt b/src/external/mpir/readme.txt
similarity index 100%
rename from distrib/lib/readme.txt
rename to src/external/mpir/readme.txt
diff --git a/distrib/lib/win32-msvc/mpir.lib b/src/external/mpir/win32-msvc/mpir.lib
similarity index 100%
rename from distrib/lib/win32-msvc/mpir.lib
rename to src/external/mpir/win32-msvc/mpir.lib
diff --git a/distrib/lib/win32-msvc/mpirxx.lib b/src/external/mpir/win32-msvc/mpirxx.lib
similarity index 100%
rename from distrib/lib/win32-msvc/mpirxx.lib
rename to src/external/mpir/win32-msvc/mpirxx.lib
diff --git a/src/meshlabplugins/filter_csg/CMakeLists.txt b/src/meshlabplugins/filter_csg/CMakeLists.txt
index d11f824ca..044d88ab7 100644
--- a/src/meshlabplugins/filter_csg/CMakeLists.txt
+++ b/src/meshlabplugins/filter_csg/CMakeLists.txt
@@ -6,7 +6,8 @@
 ### then re-run ./make-cmake.py
 
 # Only build if we have gmp/gmpxx or mpir
-if(TARGET external-gmp OR TARGET external-mpir)
+if(TARGET external-gmp OR
+		(TARGET mpir AND TARGET mpirxx))
 
     set(SOURCES filter_csg.cpp)
 
@@ -21,7 +22,8 @@ if(TARGET external-gmp OR TARGET external-mpir)
         target_compile_definitions(filter_csg PRIVATE BUILD_WITH_GMP)
         target_link_libraries(filter_csg PRIVATE external-gmp)
     else()
-        target_link_libraries(filter_csg PRIVATE external-mpir)
+		target_link_libraries(filter_csg PRIVATE mpir)
+		target_link_libraries(filter_csg PRIVATE mpirxx)
     endif()
 
     set_property(TARGET filter_csg PROPERTY FOLDER Plugins)