[clang] [flang] [llvm] [openmp] [Flang][OpenMP] Move builtin .mod generation into runtimes (PR #137828)

[David Truby via llvm-commits]

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@@ -91,6 +91,51 @@ include(CheckLibraryExists)
 include(LLVMCheckCompilerLinkerFlag)
 include(CheckCCompilerFlag)
 include(CheckCXXCompilerFlag)
+include(ExtendPath)
+
+
+# CMake 3.24 is the first version of CMake that directly recognizes Flang.
+# LLVM's requirement is only CMake 3.20, teach CMake 3.20-3.23 how to use Flang, if used.
+if (CMAKE_VERSION VERSION_LESS "3.24")
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DavidTruby wrote:

The flang support in CMake wasn't really complete/fully functional until 3.28 so I think this should be bumped up to that. Unless you've specifically tested with 3.24 and it doesn't hit the edge cases we didn't fix until later?

https://github.com/llvm/llvm-project/pull/137828