diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp b/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
--- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
@@ -2026,6 +2026,7 @@
     CompilerType clang_type;
     uint64_t uval64 = 0;
     bool uval64_valid = false;
+    bool is_default_template_arg = false;
     if (num_attributes > 0) {
       DWARFFormValue form_value;
       for (size_t i = 0; i < num_attributes; ++i) {
@@ -2056,6 +2057,11 @@
             uval64 = form_value.Unsigned();
           }
           break;
+        case DW_AT_default_value:
+          if (attributes.ExtractFormValueAtIndex(i, form_value)) {
+            is_default_template_arg = form_value.Boolean();
+          }
+          break;
         default:
           break;
         }
@@ -2078,19 +2084,21 @@
           if (!size)
             return false;
           llvm::APInt apint(*size, uval64, is_signed);
-          template_param_infos.InsertArg(
-              name,
+          auto TA =
               clang::TemplateArgument(ast, llvm::APSInt(apint, !is_signed),
-                                      ClangUtil::GetQualType(clang_type)));
+                                      ClangUtil::GetQualType(clang_type));
+          TA.setIsDefaulted(is_default_template_arg);
+          template_param_infos.InsertArg(name, std::move(TA));
         } else {
-          template_param_infos.InsertArg(
-              name,
-              clang::TemplateArgument(ClangUtil::GetQualType(clang_type)));
+          auto TA = clang::TemplateArgument(ClangUtil::GetQualType(clang_type));
+          TA.setIsDefaulted(is_default_template_arg);
+          template_param_infos.InsertArg(name, std::move(TA));
         }
       } else {
         auto *tplt_type = m_ast.CreateTemplateTemplateParmDecl(template_name);
-        template_param_infos.InsertArg(
-            name, clang::TemplateArgument(clang::TemplateName(tplt_type)));
+        auto TA = clang::TemplateArgument(clang::TemplateName(tplt_type));
+        TA.setIsDefaulted(is_default_template_arg);
+        template_param_infos.InsertArg(name, std::move(TA));
       }
     }
   }