[clang] Multilib error fixes (PR #110804)

[Peter Smith via cfe-commits]

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@@ -217,15 +215,15 @@ struct MultilibSetSerialization {
 template <> struct llvm::yaml::MappingTraits<MultilibSerialization> {
   static void mapping(llvm::yaml::IO &io, MultilibSerialization &V) {
     io.mapOptional("Dir", V.Dir);
-    io.mapOptional("FatalError", V.FatalError);
+    io.mapOptional("Error", V.Error);
     io.mapRequired("Flags", V.Flags);
     io.mapOptional("Group", V.Group);
   }
   static std::string validate(IO &io, MultilibSerialization &V) {
-    if (V.Dir.empty() && V.FatalError.empty())
-      return "one of the 'Dir' and 'FatalError' keys must be specified";
-    if (!V.Dir.empty() && !V.FatalError.empty())
-      return "the 'Dir' and 'FatalError' keys may not both be specified";
+    if (V.Dir.empty() && V.Error.empty())
+      return "one of the 'Dir' and 'atalError' keys must be specified";
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smithp35 wrote:

The 'atalError' looks like a typo. It probably means we're missing a test for that message too.

https://github.com/llvm/llvm-project/pull/110804