[clang] [C++20] Fix a crash with spaceship and vector types (PR #139767)

[Erich Keane via cfe-commits]

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@@ -8651,6 +8651,11 @@ class DefaultedComparisonAnalyzer
         assert(Best->BuiltinParamTypes[2].isNull() &&
                "invalid builtin comparison");
 
+        // FIXME: If the type we deduced is a vector type, we mark the
+        // comparison as deleted because we don't yet support this.
+        if (isa<VectorType>(T))
+          return Result::deleted();
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erichkeane wrote:

The other versions of 'deleted' all seem to diagnose first, is there a reason to not do so here? 

https://github.com/llvm/llvm-project/pull/139767