Add mpdecimal.h selection shim

Author: zware

Modules/_decimal/windows/mpdecimal.h

@@ -0,0 +1,17 @@
+/* Windows mpdecimal.h shim
+ *
+ * Generally, the mpdecimal library build will copy the correct header into
+ * place named "mpdecimal.h", but since we're building it ourselves directly
+ * into _decimal.pyd, we need to pick the right one.
+ *
+ * */
+
+#if defined(_MSC_VER)
+  #if defined(CONFIG_64)
+    #include <mpdecimal64vc.h>
+  #elif defined(CONFIG_32)
+    #include <mpdecimal32vc.h>
+  #else
+    #error "Unknown configuration!"
+  #endif
+#endif

PCbuild/_decimal.vcxproj

@@ -98,7 +98,7 @@
       <PreprocessorDefinitions Condition="'$(Platform)'=='ARM'">CONFIG_32;ANSI;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <PreprocessorDefinitions Condition="'$(Platform)'=='ARM64'">CONFIG_64;ANSI;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <PreprocessorDefinitions Condition="'$(Platform)' == 'x64'">CONFIG_64;MASM;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <AdditionalIncludeDirectories>..\Modules\_decimal;$(mpdecimalDir)\libmpdec;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <AdditionalIncludeDirectories>..\Modules\_decimal;..\Modules\_decimal\windows;$(mpdecimalDir)\libmpdec;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
     </ClCompile>
   </ItemDefinitionGroup>
   <ItemGroup>
@@ -111,7 +111,11 @@
     <ClInclude Include="..\Modules\_decimal\docstrings.h" />
     <ClInclude Include="$(mpdecimalDir)\libmpdec\fnt.h" />
     <ClInclude Include="$(mpdecimalDir)\libmpdec\fourstep.h" />
-    <ClInclude Include="$(mpdecimalDir)\libmpdec\mpdecimal.h" />
+    <ClInclude Include="..\Modules\_decimal\windows\mpdecimal.h" />
+    <ClInclude Condition="'$(Platform)' == 'Win32'" Include="$(mpdecimalDir)\libmpdec\mpdecimal32vc.h" />
+    <ClInclude Condition="'$(Platform)' == 'ARM'" Include="$(mpdecimalDir)\libmpdec\mpdecimal32vc.h" />
+    <ClInclude Condition="'$(Platform)' == 'ARM64'" Include="$(mpdecimalDir)\libmpdec\mpdecimal64vc.h" />
+    <ClInclude Condition="'$(Platform)' == 'x64'" Include="$(mpdecimalDir)\libmpdec\mpdecimal64vc.h" />
     <ClInclude Include="$(mpdecimalDir)\libmpdec\numbertheory.h" />
     <ClInclude Include="$(mpdecimalDir)\libmpdec\sixstep.h" />
     <ClInclude Include="$(mpdecimalDir)\libmpdec\transpose.h" />

PCbuild/_decimal.vcxproj.filters

@@ -45,7 +45,13 @@
     <ClInclude Include="$(mpdecimalDir)\libmpdec\fourstep.h">
       <Filter>Header Files\libmpdec</Filter>
     </ClInclude>
-    <ClInclude Include="$(mpdecimalDir)\libmpdec\mpdecimal.h">
+    <ClInclude Include="..\Modules\_decimal\windows\mpdecimal.h">
+      <Filter>Header Files\libmpdec</Filter>
+    </ClInclude>
+    <ClInclude Include="$(mpdecimalDir)\libmpdec\mpdecimal32vc.h">
+      <Filter>Header Files\libmpdec</Filter>
+    </ClInclude>
+    <ClInclude Include="$(mpdecimalDir)\libmpdec\mpdecimal64vc.h">
       <Filter>Header Files\libmpdec</Filter>
     </ClInclude>
     <ClInclude Include="$(mpdecimalDir)\libmpdec\numbertheory.h">