[lldb] Fix UB cast when encountering DW_LANG_* >= eNumLanguageTypes

lldb/include/lldb/lldb-enumerations.h

@@ -518,6 +518,7 @@ enum LanguageType {
   eLanguageTypeAssembly = 0x0031,
   eLanguageTypeC_sharp = 0x0032,
   eLanguageTypeMojo = 0x0033,
+  eLanguageTypeLastStandardLanguage = eLanguageTypeMojo,
 
   // Vendor Extensions
   // Note: Language::GetNameForLanguageType

lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp

@@ -4330,13 +4330,16 @@ SymbolFileDWARF::GetContainingDeclContext(const DWARFDIE &die) {
 }
 
 LanguageType SymbolFileDWARF::LanguageTypeFromDWARF(uint64_t val) {
+  if (val <= eLanguageTypeLastStandardLanguage)
+    return static_cast<LanguageType>(val);
+
   // Note: user languages between lo_user and hi_user must be handled
   // explicitly here.
   switch (val) {
   case DW_LANG_Mips_Assembler:
     return eLanguageTypeMipsAssembler;
   default:
-    return static_cast<LanguageType>(val);
+    return eLanguageTypeUnknown;
   }
 }
 

lldb/source/Target/Language.cpp

@@ -257,7 +257,7 @@ static uint32_t num_languages =
 LanguageType Language::GetLanguageTypeFromString(llvm::StringRef string) {
   for (const auto &L : language_names) {
     if (string.equals_insensitive(L.name))
-      return static_cast<LanguageType>(L.type);
+      return L.type;
   }
 
   return eLanguageTypeUnknown;