[compiler-rt] [llvm] [cmake] Refactor DIA SDK detection into FindDIASDK module (PR #160354)

[Ruoyu Zhong via llvm-commits]

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@@ -0,0 +1,74 @@
+# Finds the Microsoft DIA SDK and sets DIASDK_FOUND and related variables.
+#
+# This module is intended to be used both internally by LLVM's build system and
+# by consuming projects when loading LLVMConfig.cmake.
+#
+# LLVM_WINSYSROOT may be set for locating the DIA SDK.
+#
+# If successful, the following variables will be defined:
+#   DIASDK_FOUND
+#   DIASDK_INCLUDE_DIR
+#   DIASDK_LIBRARIES
+#
+# Additionally, the following import target will be defined:
+#   DIASDK::Diaguids
+
+if(NOT WIN32)
+  set(DIASDK_FOUND FALSE)
+  return()
+endif()
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ZhongRuoyu wrote:

It doesn't have to, because DIA SDK will not be found anyway if we're not building for WIN32 (which, despite its name, covers the entire set of Windows targets). As far as this project is concerned, all `find(DIASDK)` logic is guarded by `LLVM_ENABLE_DIA_SDK`, which in turn is conditioned on `MSVC`, so I don't really expect this early return to take effect.

Open to remove/update this if you find this unnecessary/inaccurate.


https://github.com/llvm/llvm-project/pull/160354