[clang] [lld] [llvm] [LLVM][Windows] Elide `PrettyStackTrace` output for usage errors (PR #140956)

[Nikita Popov via cfe-commits]

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@@ -61,11 +61,14 @@ struct ScopedFatalErrorHandler {
 /// @deprecated Use reportFatalInternalError() or reportFatalUsageError()
 /// instead.
 [[noreturn]] LLVM_ABI void report_fatal_error(const char *reason,
-                                              bool gen_crash_diag = true);
+                                              bool gen_crash_diag = true,
+                                              bool is_usage_error = false);
 [[noreturn]] LLVM_ABI void report_fatal_error(StringRef reason,
-                                              bool gen_crash_diag = true);
+                                              bool gen_crash_diag = true,
+                                              bool is_usage_error = false);
 [[noreturn]] LLVM_ABI void report_fatal_error(const Twine &reason,
-                                              bool gen_crash_diag = true);
+                                              bool gen_crash_diag = true,
+                                              bool is_usage_error = false);
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nikic wrote:

These changes don't make sense: gen_crash_diag *is* already the flag that indicates whether this is a usage error and controls whether a stack trace is displayed.

Calling reportFatalUsageError() will correctly not display a stack trace and not ask for a bug report on Linux. If this is not the case on Windows, you need to identify why there is a difference in behavior. Adding an extra flag here is certainly the wrong thing to do though.

https://github.com/llvm/llvm-project/pull/140956