diff --git a/src/misc/hash.c b/src/misc/hash.c
index 5b85cefef..7bb386925 100644
--- a/src/misc/hash.c
+++ b/src/misc/hash.c
@@ -32,7 +32,9 @@ REVISIONS:
 /* definitions local to this file only */
 
 #ifdef XSPICECM
-#define fprintf(stderr, X) cm_message_printf(X)
+#include "ngspice/cmproto.h"
+#undef fprintf
+#define fprintf(stderr, ...) cm_message_printf(__VA_ARGS__)
 #endif
 
 /* ********************** TYPE DEFINITIONS ************************* */
diff --git a/visualc/xspice/xtradev.vcxproj b/visualc/xspice/xtradev.vcxproj
index a51536f75..3e168b1ff 100644
--- a/visualc/xspice/xtradev.vcxproj
+++ b/visualc/xspice/xtradev.vcxproj
@@ -152,7 +152,7 @@
     <ClCompile>
       <Optimization>Disabled</Optimization>
       <AdditionalIncludeDirectories>icm\$(ProjectName);..\src\include;..\..\src\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>_CRT_SECURE_NO_DEPRECATE;CIDER;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_CRT_SECURE_NO_DEPRECATE;XSPICECM;CIDER;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <MinimalRebuild>false</MinimalRebuild>
       <ExceptionHandling>
       </ExceptionHandling>
@@ -184,7 +184,7 @@
       <Optimization>MaxSpeed</Optimization>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <AdditionalIncludeDirectories>icm\$(ProjectName);..\src\include;..\..\src\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>_CRT_SECURE_NO_DEPRECATE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_CRT_SECURE_NO_DEPRECATE;XSPICECM;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <ExceptionHandling>
       </ExceptionHandling>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
@@ -204,6 +204,7 @@
   </ItemDefinitionGroup>
   <ItemGroup>
     <ClCompile Include="..\..\src\misc\dstring.c" />
+    <ClCompile Include="..\..\src\misc\hash.c" />
     <ClCompile Include="icm\xtradev\aswitch\aswitch-cfunc.c">
       <AdditionalIncludeDirectories>..\..\src\xspice\%(RelativeDir);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
     </ClCompile>