使用clang Libtooling API打印完全限定类型的参数(ParmVarDecl)或字段(FieldDecl

使用clang Libtooling API打印完全限定类型的参数(ParmVarDecl)或字段(FieldDecl)的步骤如下：

导入必要的头文件：

#include "clang/AST/AST.h"
#include "clang/ASTMatchers/ASTMatchers.h"
#include "clang/ASTMatchers/ASTMatchFinder.h"
#include "clang/Tooling/CommonOptionsParser.h"
#include "clang/Tooling/Tooling.h"
#include "llvm/Support/CommandLine.h"

创建一个ASTConsumer类，用于处理AST节点：

class MyASTConsumer : public clang::ASTConsumer {
public:
  virtual bool HandleTopLevelDecl(clang::DeclGroupRef DG) {
    for (clang::DeclGroupRef::iterator I = DG.begin(), E = DG.end(); I != E; ++I) {
      clang::Decl *D = *I;
      if (clang::ParmVarDecl *PVD = llvm::dyn_cast<clang::ParmVarDecl>(D)) {
        // 处理参数(ParmVarDecl)
        llvm::outs() << "参数类型: " << PVD->getType().getAsString() << "\n";
      } else if (clang::FieldDecl *FD = llvm::dyn_cast<clang::FieldDecl>(D)) {
        // 处理字段(FieldDecl)
        llvm::outs() << "字段类型: " << FD->getType().getAsString() << "\n";
      }
    }
    return true;
  }
};

创建一个ASTMatcher类，用于匹配参数或字段：

class MyASTMatcher : public clang::ast_matchers::MatchFinder::MatchCallback {
public:
  virtual void run(const clang::ast_matchers::MatchFinder::MatchResult &Result) {
    if (const clang::ParmVarDecl *PVD = Result.Nodes.getNodeAs<clang::ParmVarDecl>("parmVarDecl")) {
      // 匹配到参数(ParmVarDecl)
      llvm::outs() << "参数类型: " << PVD->getType().getAsString() << "\n";
    } else if (const clang::FieldDecl *FD = Result.Nodes.getNodeAs<clang::FieldDecl>("fieldDecl")) {
      // 匹配到字段(FieldDecl)
      llvm::outs() << "字段类型: " << FD->getType().getAsString() << "\n";
    }
  }
};

在主函数中创建一个ClangTool对象，并注册ASTConsumer和ASTMatcher：

int main(int argc, const char **argv) {
  clang::tooling::CommonOptionsParser OptionsParser(argc, argv);
  clang::tooling::ClangTool Tool(OptionsParser.getCompilations(), OptionsParser.getSourcePathList());

  MyASTConsumer Consumer;
  Tool.setASTConsumer(&Consumer);

  MyASTMatcher Matcher;
  clang::ast_matchers::MatchFinder Finder;
  Finder.addMatcher(clang::ast_matchers::parmVarDecl().bind("parmVarDecl"), &Matcher);
  Finder.addMatcher(clang::ast_matchers::fieldDecl().bind("fieldDecl"), &Matcher);

  return Tool.run(clang::tooling::newFrontendActionFactory(&Finder).get());
}