#include #include int A(int a); int main() { int x = 0, y = 0; int z = 1; x = A(z); y = x; } int A(int a) { int m = a; ...-Go服务器开发

为了识别变量z到变量y的传递路径，我们可以使用C++抽象语法树（AST）来分析代码。以下是使用clang作为解析器的示例代码：

#include <iostream>
#include <string>
#include <vector>
#include "clang/AST/ASTConsumer.h"
#include "clang/ASTMatchers/ASTMatchFinder.h"
#include "clang/Basic/DiagnosticOptions.h"
#include "clang/Frontend/CompilerInstance.h"
#include "clang/Frontend/FrontendDiagnostic.h"
#include "clang/Lex/HeaderSearchOptions.h"
#include "clang/Lex/Lexer.h"
#include "clang/Lex/PreprocessorOptions.h"
#include "llvm/Support/CommandLine.h"

using namespace clang;
using namespace clang::ast_matchers;

class MyMatcher : public MatchFinder::MatchCallback {
public:
    virtual void run(const MatchFinder::MatchResult &Result) {
        const VarDecl *VarZ = Result.Nodes.getNodeAs<VarDecl>("varZ");
        if (VarZ) {
            const DeclRefExpr *RefZ = Result.Nodes.getNodeAs<DeclRefExpr>("refZ");
            if (RefZ && RefZ->getDecl() == VarZ) {
                const VarDecl *VarY = Result.Nodes.getNodeAs<VarDecl>("varY");
                if (VarY) {
                    std::cout << VarY->getNameAsString() << " is assigned from variable "
                              << VarZ->getNameAsString() << std::endl;
                }
            }
        }
    }
};

int main() {
    // 创建编译器实例
    CompilerInstance CI;
    CI.createDiagnostics();

    // 配置编译选项
    LangOptions LO;
    auto PPOpts = std::make_shared<PreprocessorOptions>();
    HeaderSearchOptions HSO;
    CI.getHeaderSearchOpts() = HSO;

    // 设置源码
    const std::string Code = R"(
        #include <stdio.h>
        #include <stdlib.h>

        int A(int a);

        int main() {
            int x = 0, y = 0;
            int z = 1;
            x = A(z);
            y = x;
        }

        int A(int a) {
            int m = a;
            return m;
        }
    )";

    // 创建编译器预处理器和解析器
    auto PCHandler =
        std::make_shared<PCHContainerOperations>(CI.getFileSystemOpts());
    auto FileMgr =
        std::make_shared<FileManager>(CI.getFileSystemOpts(), PCHandler);
    Preprocessor PP(CI, LO, *PPOpts, *FileMgr,
                    /*Record=*/nullptr);

    // 对源码进行标记化
    const MemoryBufferRef BufferRef(StringRef(Code), "test.cpp");
    SourceManager SM(CI.getDiagnostics(), CI.getFileManager());
    bool IsMainFileOverridden =
        PP.Initialize(BufferRef.getName(),
                      BufferRef.getMemoryBuffer(),
                      /*RemapFiles=*/{},
                      /*RemappedFilesKeepOriginalName=*/true);
    
	// 解析AST
	ASTContext &Ctx = CI.getASTContext();
	MyMatcher Matcher;

	MatchFinder Finder;
	Finder.addMatcher(varDecl(hasName("z")).bind("varZ"), &Matcher);
	Finder.addMatcher(declRefExpr(to(varDecl(hasName("z")))).bind("refZ"), &Matcher);
	Finder.addMatcher(varDecl(hasName("y")).bind("varY"), &Matcher);

	Ctx.getDiagnostics().setIgnoreAllWarnings(true); // 忽略所有警告
	Finder.matchAST(Ctx);

	return 0;
}

运行上述代码后，会输出以下信息：