[clang] Add support for builtin_verbose_trap (PR #79230)

[Akira Hatanaka via cfe-commits]

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@@ -27,6 +27,9 @@ namespace llvm {
   }
 }
 
+// Prefix for __builtin_verbose_trap.
+#define CLANG_VERBOSE_TRAP_PREFIX "__llvm_verbose_trap"
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ahatanak wrote:

I can make it a C++ constant if that's preferable.

https://github.com/llvm/llvm-project/pull/79230