diff --git a/lib/valueflow.cpp b/lib/valueflow.cpp
index 6cf0a2fd8..b822eefc2 100644
--- a/lib/valueflow.cpp
+++ b/lib/valueflow.cpp
@@ -570,14 +570,28 @@ static void setTokenValue(Token* tok, const ValueFlow::Value &value)
     }
 }
 
+
+// Handle various constants..
+static void valueFlowSetConstantValue(const Token *tok)
+{
+    if ((tok->isNumber() && MathLib::isInt(tok->str())) || (tok->tokType() == Token::eChar)) {
+        ValueFlow::Value value(MathLib::toLongNumber(tok->str()));
+        value.setKnown();
+        setTokenValue(const_cast<Token *>(tok), value);
+    }
+
+    if (tok->enumerator() && tok->enumerator()->value_known) {
+        ValueFlow::Value value(tok->enumerator()->value);
+        value.setKnown();
+        setTokenValue(const_cast<Token *>(tok), value);
+    }
+}
+
+
 static void valueFlowNumber(TokenList *tokenlist)
 {
     for (Token *tok = tokenlist->front(); tok; tok = tok->next()) {
-        if ((tok->isNumber() && MathLib::isInt(tok->str())) || (tok->tokType() == Token::eChar)) {
-            ValueFlow::Value value(MathLib::toLongNumber(tok->str()));
-            value.setKnown();
-            setTokenValue(tok, value);
-        }
+        valueFlowSetConstantValue(tok);
     }
 
     if (tokenlist->isCPP()) {
@@ -2363,6 +2377,16 @@ static void valueFlowFunctionReturn(TokenList *tokenlist, ErrorLogger *errorLogg
     }
 }
 
+void ValueFlow::valueFlowConstantFoldAST(const Token *expr)
+{
+    if (!expr || !expr->values.empty())
+        return;
+    valueFlowConstantFoldAST(expr->astOperand1());
+    valueFlowConstantFoldAST(expr->astOperand2());
+    valueFlowSetConstantValue(expr);
+}
+
+
 void ValueFlow::setValues(TokenList *tokenlist, SymbolDatabase* symboldatabase, ErrorLogger *errorLogger, const Settings *settings)
 {
     for (Token *tok = tokenlist->front(); tok; tok = tok->next())
@@ -2400,3 +2424,5 @@ std::string ValueFlow::eitherTheConditionIsRedundant(const Token *condition)
     }
     return "Either the condition '" + condition->expressionString() + "' is redundant";
 }
+
+
diff --git a/lib/valueflow.h b/lib/valueflow.h
index 31454d118..1beec7934 100644
--- a/lib/valueflow.h
+++ b/lib/valueflow.h
@@ -94,6 +94,10 @@ namespace ValueFlow {
         }
     };
 
+    /// Constant folding of expression. This can be used before the full ValueFlow has been executed (ValueFlow::setValues).
+    void valueFlowConstantFoldAST(const Token *expr);
+
+    /// Perform valueflow analysis.
     void setValues(TokenList *tokenlist, SymbolDatabase* symboldatabase, ErrorLogger *errorLogger, const Settings *settings);
 
     std::string eitherTheConditionIsRedundant(const Token *condition);
diff --git a/test/testvalueflow.cpp b/test/testvalueflow.cpp
index 4a613afb1..baed0d96e 100644
--- a/test/testvalueflow.cpp
+++ b/test/testvalueflow.cpp
@@ -164,11 +164,12 @@ private:
     }
 
     void valueFlowNumber() {
-        ASSERT_EQUALS(123, valueOfTok("x=123;",   "123").intvalue);
+        ASSERT_EQUALS(123, valueOfTok("x=123;", "123").intvalue);
+        ASSERT_EQUALS(10, valueOfTok("enum {A=10,B=15}; x=A+0;", "+").intvalue);
         ASSERT_EQUALS(0, valueOfTok("x=false;", "false").intvalue);
-        ASSERT_EQUALS(1, valueOfTok("x=true;",  "true").intvalue);
-        ASSERT_EQUALS(0, valueOfTok("x(NULL);",  "NULL").intvalue);
-        ASSERT_EQUALS((int)('a'), valueOfTok("x='a';",  "'a'").intvalue);
+        ASSERT_EQUALS(1, valueOfTok("x=true;", "true").intvalue);
+        ASSERT_EQUALS(0, valueOfTok("x(NULL);", "NULL").intvalue);
+        ASSERT_EQUALS((int)('a'), valueOfTok("x='a';", "'a'").intvalue);
         ASSERT_EQUALS((int)('\n'), valueOfTok("x='\\n';", "'\\n'").intvalue);
     }