Fix #12151 (Tokenizer::arraySize: enum constant used as index in array initialization) (#5633)

lib/symboldatabase.h

@@ -553,6 +553,10 @@ public:
         return mDimensions.at(index_).known;
     }
 
+    void setDimensions(const std::vector<Dimension> &dimensions_) {
+        mDimensions = dimensions_;
+    }
+
     /**
      * Checks if the variable is an STL type ('std::')
      * E.g.:

lib/tokenize.cpp

@@ -3393,6 +3393,8 @@ bool Tokenizer::simplifyTokens1(const std::string &configuration)
         } else {
             ValueFlow::setValues(list, *mSymbolDatabase, mErrorLogger, mSettings, mTimerResults);
         }
+
+        arraySizeAfterValueFlow();
     }
 
     // Warn about unhandled character literals
@@ -3807,6 +3809,45 @@ void Tokenizer::arraySize()
     }
 }
 
+void Tokenizer::arraySizeAfterValueFlow()
+{
+    // After ValueFlow, adjust array sizes.
+    for (const Variable* var: mSymbolDatabase->variableList()) {
+        if (!var || !var->isArray())
+            continue;
+        if (!Token::Match(var->nameToken(), "%name% [ ] = { ["))
+            continue;
+        MathLib::bigint maxIndex = -1;
+        const Token* const startToken = var->nameToken()->tokAt(4);
+        const Token* const endToken = startToken->link();
+        for (const Token* tok = startToken; tok != endToken; tok = tok->next()) {
+            if (!Token::Match(tok, "[{,] [") || !Token::simpleMatch(tok->linkAt(1), "] ="))
+                continue;
+            const Token* expr = tok->next()->astOperand1();
+            if (expr && expr->hasKnownIntValue())
+                maxIndex = std::max(maxIndex, expr->getKnownIntValue());
+        }
+        if (maxIndex >= 0) {
+            // insert array size
+            Token* tok = const_cast<Token*>(var->nameToken()->next());
+            tok->insertToken(std::to_string(maxIndex + 1));
+            // ast
+            tok->astOperand2(tok->next());
+            // Token::scope
+            tok->next()->scope(tok->scope());
+            // Value flow
+            ValueFlow::Value value(maxIndex + 1);
+            value.setKnown();
+            tok->next()->addValue(value);
+            // Set array dimensions
+            Dimension d;
+            d.num = maxIndex + 1;
+            std::vector<Dimension> dimensions{d};
+            const_cast<Variable*>(var)->setDimensions(dimensions);
+        }
+    }
+}
+
 static Token *skipTernaryOp(Token *tok)
 {
     int colonLevel = 1;

lib/tokenize.h

@@ -164,6 +164,7 @@ public:
 
     /** Insert array size where it isn't given */
     void arraySize();
+    void arraySizeAfterValueFlow(); // cppcheck-suppress functionConst
 
     /** Simplify labels and 'case|default' syntaxes.
      */

test/testtokenize.cpp

@@ -272,6 +272,7 @@ private:
         TEST_CASE(cpp14template); // Ticket #6708
 
         TEST_CASE(arraySize);
+        TEST_CASE(arraySizeAfterValueFlow);
 
         TEST_CASE(labels);
         TEST_CASE(simplifyInitVar);
@@ -4156,6 +4157,11 @@ private:
         ASSERT_EQUALS("; const char c [ 4 ] = \"abc\" ;", tokenizeAndStringify(";const char c[] = { \"abc\" };"));
     }
 
+    void arraySizeAfterValueFlow() {
+        const char code[] = "enum {X=10}; int a[] = {[X]=1};";
+        ASSERT_EQUALS("enum Anonymous0 { X = 10 } ; int a [ 11 ] = { [ X ] = 1 } ;", tokenizeAndStringify(code));
+    }
+
     void labels() {
         ASSERT_EQUALS("void f ( ) { ab : ; a = 0 ; }", tokenizeAndStringify("void f() { ab: a=0; }"));
         //ticket #3176