Clang-检索ParmVarDecl的初始化值

如何解决Clang-检索ParmVarDecl的初始化值

我有一个ForStmt，我想为其检索GetBoundFunc()返回的循环绑定，如下所示：

void testASTVistor (int N) {
  N = 123;
  for (int i = 0; i <= GetBoundFunc(N); i++ ){
    //do Sth;
  }  
}

AST对于N看起来像这样：

 -FunctionDecl 0x55d60e61cd48 <line:3:1,line:8:1> line:3:6 testASTVistor 'void (int)'
  |-ParmVarDecl 0x55d60e61cc88 <col:21,col:25> col:25 used N 'int'
  `-CompoundStmt 0x55d60e61d0e8 <col:28,line:8:1>
  ¦ |-BinaryOperator 0x55d60e61ce28 <line:4:3,col:7> 'int' lvalue '='
  ¦ | |-DeclRefExpr 0x55d60e61cde8 <col:3> 'int' lvalue ParmVar 0x55d60e61cc88 'N' 'int'
  ¦ | `-IntegerLiteral 0x55d60e61ce08 <col:7> 'int' 123

但是，当我的ASTRecurvieVisitor代码应返回N的初始化值时，它会不断出现段错误：

class BinaryVisitor : public clang::RecursiveASTVisitor<BinaryVisitor> {
public:
  bool VisitBinaryOperator(clang::BinaryOperator *BO) {
  
      if (const CallExpr *RHS = dyn_cast<CallExpr>(BO->getRHS()->IgnoreParenImpCasts())) {
        if (const DeclRefExpr *DRE = dyn_cast_or_null<DeclRefExpr>(RHS->getArg(0))) {
          if (const ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(DRE->getDecl())) {       
            if (const IntegerLiteral *Bound = dyn_cast<IntegerLiteral>(PVD->getinit()->ignoreImpCasts())) {

    return false;
            }
          }
        }
};

/// ...
BinaryVisitor visitor;
visitor.TraverseDecl(someDecl); 

evaluateValue()和getEvaluatedValue()也尝试过，似乎没有人绕过这个问题。