Index: cmake/modules/AddLLVM.cmake
===================================================================
--- cmake/modules/AddLLVM.cmake
+++ cmake/modules/AddLLVM.cmake
@@ -1531,7 +1531,7 @@
     endif()
   endif()
 
-  if(CMAKE_HOST_UNIX)
+  if(CMAKE_HOST_UNIX OR MSYS)
     set(LLVM_LINK_OR_COPY create_symlink)
   else()
     set(LLVM_LINK_OR_COPY copy)
Index: cmake/modules/LLVMInstallSymlink.cmake
===================================================================
--- cmake/modules/LLVMInstallSymlink.cmake
+++ cmake/modules/LLVMInstallSymlink.cmake
@@ -3,7 +3,7 @@
 # See PR8397.
 
 function(install_symlink name target outdir)
-  if(CMAKE_HOST_UNIX)
+  if(CMAKE_HOST_UNIX OR MSYS)
     set(LINK_OR_COPY create_symlink)
     set(DESTDIR $ENV{DESTDIR})
   else()