diff --git a/lib/errorlogger.cpp b/lib/errorlogger.cpp
index 466452a3a..b4eb0fdc3 100644
--- a/lib/errorlogger.cpp
+++ b/lib/errorlogger.cpp
@@ -37,6 +37,9 @@ InternalError::InternalError(const Token *tok, const std::string &errorMsg, Type
     token(tok), errorMessage(errorMsg)
 {
     switch (type) {
+    case AST:
+        id = "internalAstError";
+        break;
     case SYNTAX:
         id = "syntaxError";
         break;
diff --git a/lib/errorlogger.h b/lib/errorlogger.h
index 2569f6c77..5473d7dc9 100644
--- a/lib/errorlogger.h
+++ b/lib/errorlogger.h
@@ -54,7 +54,7 @@ namespace tinyxml2 {
 
 /** @brief Simple container to be thrown when internal error is detected. */
 struct InternalError {
-    enum Type {SYNTAX, INTERNAL};
+    enum Type {AST, SYNTAX, INTERNAL};
     InternalError(const Token *tok, const std::string &errorMsg, Type type = INTERNAL);
     const Token *token;
     std::string errorMessage;
diff --git a/lib/tokenlist.cpp b/lib/tokenlist.cpp
index d4ed68218..76f95bf47 100644
--- a/lib/tokenlist.cpp
+++ b/lib/tokenlist.cpp
@@ -1128,11 +1128,11 @@ void TokenList::validateAst() const
     for (const Token *tok = _front; tok; tok = tok->next()) {
         // Syntax error if binary operator only has 1 operand
         if ((tok->isAssignmentOp() || tok->isComparisonOp() || Token::Match(tok,"[|^/%]")) && tok->astOperand1() && !tok->astOperand2())
-            throw InternalError(tok, "Syntax Error: AST broken, binary operator has only one operand.", InternalError::SYNTAX);
+            throw InternalError(tok, "Syntax Error: AST broken, binary operator has only one operand.", InternalError::AST);
 
         // Syntax error if we encounter "?" with operand2 that is not ":"
         if (tok->astOperand2() && tok->str() == "?" && tok->astOperand2()->str() != ":")
-            throw InternalError(tok, "Syntax Error: AST broken, ternary operator lacks ':'.", InternalError::SYNTAX);
+            throw InternalError(tok, "Syntax Error: AST broken, ternary operator lacks ':'.", InternalError::AST);
 
         // Check for endless recursion
         const Token* parent=tok->astParent();
@@ -1143,7 +1143,7 @@ void TokenList::validateAst() const
                 if (safeAstTokens.find(parent) != safeAstTokens.end())
                     break;
                 if (astTokens.find(parent) != astTokens.end())
-                    throw InternalError(tok, "AST broken: endless recursion from '" + tok->str() + "'", InternalError::SYNTAX);
+                    throw InternalError(tok, "AST broken: endless recursion from '" + tok->str() + "'", InternalError::AST);
                 astTokens.insert(parent);
             } while ((parent = parent->astParent()) != nullptr);
             safeAstTokens.insert(astTokens.begin(), astTokens.end());