[llvm] [openmp] Deprecate LLVM_ENABLE_PROJECTS in favor of LLVM_ENABLE_RUNTIMES (PR #124711)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-openmp

Author: Petr Hosek (petrhosek)

<details>
<summary>Changes</summary>

We plan to make this a hard error in the LLVM 21 release.

Link #<!-- -->124014

---
Full diff: https://github.com/llvm/llvm-project/pull/124711.diff


1 Files Affected:

- (modified) llvm/CMakeLists.txt (+7) 


``````````diff
diff --git a/llvm/CMakeLists.txt b/llvm/CMakeLists.txt
index c9ff3696e22d69..4cb4e90fa5c7e8 100644
--- a/llvm/CMakeLists.txt
+++ b/llvm/CMakeLists.txt
@@ -164,6 +164,13 @@ if ("compiler-rt" IN_LIST LLVM_ENABLE_PROJECTS)
     "https://compiler-rt.llvm.org/ for building the runtimes.")
 endif()
 
+if ("openmp" IN_LIST LLVM_ENABLE_PROJECTS)
+  message(WARNING "Using LLVM_ENABLE_PROJECTS=openmp is deprecated now, and will "
+    "become a fatal error in the LLVM 21 release.  Please use "
+    "-DLLVM_ENABLE_RUNTIMES=openmp or see the instructions at "
+    "https://openmp.llvm.org/ for building the runtimes.")
+endif()
+
 # Select the runtimes to build
 #
 # As we migrate runtimes to using the bootstrapping build, the set of default runtimes

``````````

</details>


https://github.com/llvm/llvm-project/pull/124711