Internals: Fix some -Wsuggest-attribute=const suggestions.

src/V3Ast.cpp

@@ -690,9 +690,6 @@ void AstNode::deleteNode() {
     // and we can debug easier.
 }
 
-AstNode::~AstNode() {
-}
-
 void AstNode::deleteTreeIter() {
     // private: Delete list of nodes. Publicly call deleteTree() instead.
     // Audited to make sure this is never NULL

src/V3Ast.h

@@ -1229,7 +1229,7 @@ public:
     bool	brokeExistsAbove() const;
 
     // CONSTRUCTORS
-    virtual ~AstNode();
+    virtual ~AstNode() {}
 #ifdef VL_LEAK_CHECKS
     static void* operator new(size_t size);
     static void operator delete(void* obj, size_t size);

src/V3GraphTest.cpp

@@ -327,8 +327,11 @@ public:
 
 class V3GraphTestImport : public V3GraphTest {
 
-    // cppcheck-suppress functionConst
+#ifdef GRAPH_IMPORT
     void dotImport();
+#else
+    void dotImport() {}
+#endif
 
 public:
     virtual string name() { return "import"; }
@@ -344,11 +347,8 @@ public:
     }
 };
 
-#if 0
+#ifdef GRAPH_IMPORT
 # include "graph_export.cpp"
-#else
-void V3GraphTestImport::dotImport() {
-}
 #endif
 
 //======================================================================

src/V3Number.cpp

@@ -287,8 +287,8 @@ void V3Number::setNames(AstNode* nodep) {
 
 int V3Number::log2b(uint32_t num) {
     // See also opCLog2
-    for (int bit=31; bit>0; bit--) if (num & (VL_ULL(1)<<bit)) return(bit);
-    return(0);
+    for (int bit=31; bit>0; bit--) if (num & (VL_ULL(1)<<bit)) return bit;
+    return 0;
 }
 
 //======================================================================

src/V3PreProc.cpp

@@ -170,7 +170,7 @@ public:
 	fileline()->v3errorEnd(str);
     }
 
-    const char* tokenName(int tok);
+    static const char* tokenName(int tok);
     void debugToken(int tok, const char* cmtp);
     void parseTop();
     void parseUndef();