[clang] [Clang] Add #pragma clang deprecated_header (PR #168041)

[Aaron Ballman via cfe-commits]

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@@ -0,0 +1,13 @@
+// RUN: %clang_cc1 -Wdeprecated %s -fsyntax-only -verify -Wunknown-pragmas -Wextra-tokens
+
+#pragma clang deprecated_header( // expected-error {{expected string literal in #pragma clang deprecated_header}}
+#pragma clang deprecated_header() // expected-error {{expected string literal in #pragma clang deprecated_header}}
+#pragma clang deprecated_header("" // expected-error {{expected )}}
+#pragma clang deprecated_header something // expected-warning {{extra tokens at end of #pragma clang deprecated_header directive}}
+#pragma clang deprecated_header("") something // expected-warning {{extra tokens at end of #pragma clang deprecated_header directive}}
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AaronBallman wrote:

We should also have a test that we reject writing this in a source file.

https://github.com/llvm/llvm-project/pull/168041