[llvm] [mlir] [mlir][Python] create MLIRPythonSupport (PR #171775)

[Maksim Levental via llvm-commits]

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@@ -297,6 +302,58 @@ function(_mlir_python_install_sources name source_root_dir destination)
   )
 endfunction()
 
+function(build_nanobind_lib)
+  cmake_parse_arguments(ARG
+    ""
+    "INSTALL_COMPONENT;INSTALL_DESTINATION;OUTPUT_DIRECTORY;MLIR_BINDINGS_PYTHON_NB_DOMAIN"
+    ""
+    ${ARGN})
+
+  # Only build in free-threaded mode if the Python ABI supports it.
+  # See https://github.com/wjakob/nanobind/blob/4ba51fcf795971c5d603d875ae4184bc0c9bd8e6/cmake/nanobind-config.cmake#L363-L371.
+  if (NB_ABI MATCHES "[0-9]t")
+    set(_ft "-ft")
+  endif()
+  # nanobind does a string match on the suffix to figure out whether to build
+  # the lib with free threading...
+  set(NB_LIBRARY_TARGET_NAME "nanobind${_ft}-${ARG_MLIR_BINDINGS_PYTHON_NB_DOMAIN}")
+  set(NB_LIBRARY_TARGET_NAME "${NB_LIBRARY_TARGET_NAME}" PARENT_SCOPE)
+  nanobind_build_library(${NB_LIBRARY_TARGET_NAME} AS_SYSINCLUDE)
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makslevental wrote:

This is their blessed way of silencing all of the warnings we usually get https://github.com/wjakob/nanobind/blob/4ba51fcf795971c5d603d875ae4184bc0c9bd8e6/cmake/nanobind-config.cmake#L390

https://github.com/llvm/llvm-project/pull/171775