[Mlir-commits] [mlir] [MLIR][Python] Add LLVM include directories to mlir-py cmake (PR #181779)

[Jakub Kuderski]

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@@ -8,6 +8,19 @@
 # nomenclature, adds libraries.
 ################################################################################
 
+# INTERFACE library that provides the include directories needed to compile
+# against MLIR CAPI headers. The CAPI headers (e.g., mlir/CAPI/Wrap.h)
+# transitively include LLVM headers (via mlir/Support/LLVM.h), so consumers
+# need the LLVM include paths even if they don't link against LLVMSupport.
+# Defined here (rather than in lib/CAPI/) so it is available to both in-tree
+# and external project builds that include this module.
+if(NOT TARGET MLIRCAPIHeaderDeps)
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kuhar wrote:

Why do we need this outer `if` statement?

https://github.com/llvm/llvm-project/pull/181779