[llvm] [orc-rt] add a check to ensure the headers on disk match what we install via the fileset. (PR #216482)

[Lang Hames via llvm-commits]

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@@ -46,30 +52,50 @@ set(ORC_RT_HEADERS
     orc-rt/sps-ci/MemoryAccessSPSCI.h
     orc-rt/sps-ci/NativeDylibManagerSPSCI.h
     orc-rt/sps-ci/SimpleNativeMemoryMapSPSCI.h
+    orc-rt/sps-ci/StandaloneMachOUnwindInfoRegistrarSPSCI.h
 )
+#LLVM prefers not to use globs, so we just use it to assert that the list is up to date.
+file(GLOB_RECURSE ORC_RT_DISK_INCLUDES
+  RELATIVE ${CMAKE_CURRENT_SOURCE_DIR}
+  CONFIGURE_DEPENDS
+  ${CMAKE_CURRENT_SOURCE_DIR}/*.h)
+
+set(ORC_RT_NOT_INCLUDED ${ORC_RT_DISK_INCLUDES})
+if(ORC_RT_HEADERS)
+  list(REMOVE_ITEM ORC_RT_NOT_INCLUDED ${ORC_RT_HEADERS})
+endif()
+
+set(ORC_RT_STALE ${ORC_RT_HEADERS})
+if(ORC_RT_DISK_INCLUDES)
+  list(REMOVE_ITEM ORC_RT_STALE ${ORC_RT_DISK_INCLUDES})
+endif()
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lhames wrote:

Can we fatal-error if ORC_RT_HEADERS isn't set? We definitely expect it to be for these checks.

https://github.com/llvm/llvm-project/pull/216482