From 7b61b7b515cc077e2ce76505cad94c4268ef2bb4 Mon Sep 17 00:00:00 2001
From: Curtis J Bezault <curtbezault@gmail.com>
Date: Thu, 9 Jan 2020 14:27:03 -0800
Subject: [PATCH] Allow ARM64 to build x86 things (#9578)

---
 toolsrc/src/vcpkg/base/system.cpp | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/toolsrc/src/vcpkg/base/system.cpp b/toolsrc/src/vcpkg/base/system.cpp
index d9c6349be8..c84b7f8be4 100644
--- a/toolsrc/src/vcpkg/base/system.cpp
+++ b/toolsrc/src/vcpkg/base/system.cpp
@@ -157,11 +157,24 @@ namespace vcpkg
         std::vector<CPUArchitecture> supported_architectures;
         supported_architectures.push_back(get_host_processor());
 
-        // AMD64 machines support to run x86 applications
+        // AMD64 machines support running x86 applications and ARM64 machines support running ARM applications
         if (supported_architectures.back() == CPUArchitecture::X64)
         {
             supported_architectures.push_back(CPUArchitecture::X86);
         }
+        else if (supported_architectures.back() == CPUArchitecture::ARM64)
+        {
+            supported_architectures.push_back(CPUArchitecture::ARM);
+        }
+
+#if defined(_WIN32)
+        // On ARM32/64 Windows we can rely on x86 emulation
+        if (supported_architectures.front() == CPUArchitecture::ARM ||
+            supported_architectures.front() == CPUArchitecture::ARM64)
+        {
+            supported_architectures.push_back(CPUArchitecture::X86);
+        }
+#endif
 
         return supported_architectures;
     }