[clang] [clang] Don't warn on __COUNTER__ in system macros (PR #196689)

[Aaron Ballman via cfe-commits]

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@@ -0,0 +1,7 @@
+#define COUNTER_ALIAS __COUNTER__
+#define COUNTER_MACRO() __COUNTER__
+
+int header_counter_value = __COUNTER__;
+int header_counter_alias = COUNTER_ALIAS;
+int header_counter_macro = COUNTER_MACRO();
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AaronBallman wrote:

Can you also add a test case like what's happening in https://github.com/llvm/llvm-project/issues/196474 ? I believe that issue should also be resolved by these changes.

https://github.com/llvm/llvm-project/pull/196689