diff --git a/build.vc/postbuild.bat b/build.vc/postbuild.bat
index de1ed08..e4ecceb 100644
--- a/build.vc/postbuild.bat
+++ b/build.vc/postbuild.bat
@@ -37,12 +37,10 @@ set bin_dir="..\%extn%\%plat%\%conf%\"
 set hdr_dir="..\%extn%\%plat%\%conf%\"
 
 rem output parametrers for the MPIR tests
-if /i "%filename%" EQU "mpirxx" goto skip 
 echo (set ldir=%loc%)   > output_params.bat
 echo (set libr=%extn%) >> output_params.bat
 echo (set plat=%plat%) >> output_params.bat
 echo (set conf=%conf%) >> output_params.bat
-:skip
 
 echo copying outputs from %tgt_dir% to %bin_dir%
 if not exist %bin_dir% md %bin_dir%
diff --git a/build.vc15/lib_mpir_cxx/lib_mpir_cxx.vcxproj b/build.vc15/lib_mpir_cxx/lib_mpir_cxx.vcxproj
index 3a23f01..1f44b22 100644
--- a/build.vc15/lib_mpir_cxx/lib_mpir_cxx.vcxproj
+++ b/build.vc15/lib_mpir_cxx/lib_mpir_cxx.vcxproj
@@ -70,6 +70,11 @@
     <TargetName Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">mpirxx</TargetName>
   </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
+    <PreBuildEvent>
+      <Command>cd ..\..\build.vc
+prebuild gc Win32 15
+      </Command>
+    </PreBuildEvent>
     <ClCompile>
       <AdditionalIncludeDirectories>..\..\</AdditionalIncludeDirectories>
       <PreprocessorDefinitions>NDEBUG;WIN32;_LIB;HAVE_CONFIG_H;%(PreprocessorDefinitions)</PreprocessorDefinitions>
@@ -82,6 +87,11 @@ postbuild "$(TargetPath)" 15
     </PostBuildEvent>
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
+    <PreBuildEvent>
+      <Command>cd ..\..\build.vc
+prebuild gc Win32 15
+      </Command>
+    </PreBuildEvent>
     <ClCompile>
       <AdditionalIncludeDirectories>..\..\</AdditionalIncludeDirectories>
       <PreprocessorDefinitions>_DEBUG;WIN32;_LIB;HAVE_CONFIG_H;%(PreprocessorDefinitions)</PreprocessorDefinitions>
@@ -94,6 +104,11 @@ postbuild "$(TargetPath)" 15
     </PostBuildEvent>
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'">
+    <PreBuildEvent>
+      <Command>cd ..\..\build.vc
+prebuild gc Win32 15
+      </Command>
+    </PreBuildEvent>
     <ClCompile>
       <AdditionalIncludeDirectories>..\..\</AdditionalIncludeDirectories>
       <PreprocessorDefinitions>NDEBUG;WIN32;_LIB;HAVE_CONFIG_H;_WIN64;%(PreprocessorDefinitions)</PreprocessorDefinitions>
@@ -106,6 +121,11 @@ postbuild "$(TargetPath)" 15
     </PostBuildEvent>
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
+    <PreBuildEvent>
+      <Command>cd ..\..\build.vc
+prebuild gc Win32 15
+      </Command>
+    </PreBuildEvent>
     <ClCompile>
       <AdditionalIncludeDirectories>..\..\</AdditionalIncludeDirectories>
       <PreprocessorDefinitions>_DEBUG;WIN32;_LIB;HAVE_CONFIG_H;_WIN64;%(PreprocessorDefinitions)</PreprocessorDefinitions>