[llvm] [mlir] Shard the public llvm-config.h in multiple files (NFC) (PR #71273)

[Alexander Richardson via llvm-commits]

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@@ -0,0 +1,16 @@
+/*===------- llvm/Config/llvm-config-enable-curl.h.cmake ----------*- C -*-===*/
+/*                                                                            */
+/* Part of the LLVM Project, under the Apache License v2.0 with LLVM          */
+/* Exceptions.                                                                */
+/* See https://llvm.org/LICENSE.txt for license information.                  */
+/* SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception                    */
+/*                                                                            */
+/*===----------------------------------------------------------------------===*/
+
+#ifndef LLVM_CONFIG_ENABLE_CURL_H
+#define LLVM_CONFIG_ENABLE_CURL_H
+
+/* Define if we have curl and want to use it */
+#cmakedefine LLVM_ENABLE_CURL ${LLVM_ENABLE_CURL}
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arichardson wrote:

I worry that this split is going to cause subtle bugs if we don't use cmakedefine01 everywhere. Otherwise we could end up with #ifndef being evaluated incorrectly.

https://github.com/llvm/llvm-project/pull/71273