[libunwind] [libunwind] introduce _LIBUNWIND_TRACE_DWARF_EVAL for increased baremetal friendliness (PR #72040)

[Alexander Richardson via cfe-commits]

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@@ -223,6 +223,21 @@
     } while (0)
 #endif
 
+#define _LIBUNWIND_TRACING_DWARF_EVAL (0)
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arichardson wrote:

Maybe it would be best to follow the same pattern as above and allow turning it on for debug builds? But seeing as it's always been hardcoded to false, maybe the current preprocessor define makes more sense. It should be very rare that this kind of tracing is needed and a debugger might be better.

https://github.com/llvm/llvm-project/pull/72040