[llvm] Revert "[Cygwin] Define LLVM_ABI for Cygwin (#143222)" (PR #144210)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-llvm-support

Author: Tomohiro Kashiwada (kikairoya)

<details>
<summary>Changes</summary>

Flang Merge CI rejects changes to llvm/Support/Compiler.h because precompiled headers aren't rebuilt when their dependencies change.

This reverts commit 60d000496b5485c89c51e64b2b339210d48263be.

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Full diff: https://github.com/llvm/llvm-project/pull/144210.diff


1 Files Affected:

- (modified) llvm/include/llvm/Support/Compiler.h (+1-1) 


``````````diff
diff --git a/llvm/include/llvm/Support/Compiler.h b/llvm/include/llvm/Support/Compiler.h
index 0de789ec68c49..f6bc05011e3c3 100644
--- a/llvm/include/llvm/Support/Compiler.h
+++ b/llvm/include/llvm/Support/Compiler.h
@@ -209,7 +209,7 @@
 #define LLVM_ABI_FRIEND LLVM_ABI
 #define LLVM_ABI_EXPORT __declspec(dllexport)
 #elif defined(__ELF__) || defined(__MINGW32__) || defined(_AIX) ||             \
-    defined(__MVS__) || defined(__CYGWIN__)
+    defined(__MVS__)
 #define LLVM_ABI LLVM_ATTRIBUTE_VISIBILITY_DEFAULT
 #define LLVM_ABI_FRIEND
 #define LLVM_TEMPLATE_ABI LLVM_ATTRIBUTE_VISIBILITY_DEFAULT

``````````

</details>


https://github.com/llvm/llvm-project/pull/144210