VS: Teach VS 2019 generator to select host tools matching host arch

This generator is new so we can introduce the long-desired behavior
of selecting ``host=x64`` tools by default on x64 hosts.

1 files changed, 18 insertions, 0 deletions

diff --git a/Source/cmGlobalVisualStudioVersionedGenerator.cxx b/Source/cmGlobalVisualStudioVersionedGenerator.cxx
index b019f39..bc6b453 100644
--- a/Source/cmGlobalVisualStudioVersionedGenerator.cxx
+++ b/Source/cmGlobalVisualStudioVersionedGenerator.cxx
@@ -11,10 +11,13 @@
 
 #if defined(_M_ARM64)
 #  define HOST_PLATFORM_NAME "ARM64"
+#  define HOST_TOOLS_ARCH ""
 #elif defined(_M_ARM)
 #  define HOST_PLATFORM_NAME "ARM"
+#  define HOST_TOOLS_ARCH ""
 #elif defined(_M_IA64)
 #  define HOST_PLATFORM_NAME "Itanium"
+#  define HOST_TOOLS_ARCH ""
 #else
 #  include "cmsys/SystemInformation.hxx"
 #endif
@@ -33,6 +36,20 @@ static std::string VSHostPlatformName()
 #endif
 }
 
+static std::string VSHostArchitecture()
+{
+#ifdef HOST_TOOLS_ARCH
+  return HOST_TOOLS_ARCH;
+#else
+  cmsys::SystemInformation info;
+  if (info.Is64Bits()) {
+    return "x64";
+  } else {
+    return "x86";
+  }
+#endif
+}
+
 static unsigned int VSVersionToMajor(
   cmGlobalVisualStudioGenerator::VSVersion v)
 {
@@ -262,6 +279,7 @@ cmGlobalVisualStudioVersionedGenerator::cmGlobalVisualStudioVersionedGenerator(
   this->DefaultLinkFlagTableName = VSVersionToToolset(this->Version);
   if (this->Version >= cmGlobalVisualStudioGenerator::VS16) {
     this->DefaultPlatformName = VSHostPlatformName();
+    this->DefaultPlatformToolsetHostArchitecture = VSHostArchitecture();
   }
 }