另一个我认为比模糊解析更适合 OP 的解决方案。
在解析时，clang 通过分析器的 Sema 部分维护语义信息。当遇到未知符号时，Sema 将回退到 ExternalSemaSource 来获取有关此符号的一些信息。通过这种方式，您可以实现您想要的功能。
这是一个快速设置它的示例。它不是完全功能的（我在 LookupUnqualified 方法中没有做任何事情），您可能需要进行进一步的调查，我认为这是一个很好的开始。
#include <clang/Frontend/FrontendActions.h>
#include <clang/Tooling/CommonOptionsParser.h>
#include <clang/Tooling/Tooling.h>
#include <llvm/Support/CommandLine.h>
#include <clang/AST/AST.h>
#include <clang/AST/ASTConsumer.h>
#include <clang/AST/RecursiveASTVisitor.h>
#include <clang/Frontend/ASTConsumers.h>
#include <clang/Frontend/FrontendActions.h>
#include <clang/Frontend/CompilerInstance.h>
#include <clang/Tooling/CommonOptionsParser.h>
#include <clang/Tooling/Tooling.h>
#include <clang/Rewrite/Core/Rewriter.h>
#include <llvm/Support/raw_ostream.h>
#include <clang/Sema/ExternalSemaSource.h>
#include <clang/Sema/Sema.h>
#include "clang/Basic/DiagnosticOptions.h"
#include "clang/Frontend/TextDiagnosticPrinter.h"
#include "clang/Frontend/CompilerInstance.h"
#include "clang/Basic/TargetOptions.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/Basic/FileManager.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Lex/Preprocessor.h"
#include "clang/Basic/Diagnostic.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/ASTConsumer.h"
#include "clang/Parse/Parser.h"
#include "clang/Parse/ParseAST.h"
#include <clang/Sema/Lookup.h>
#include <iostream>
using namespace clang;
using namespace clang::tooling;
using namespace llvm;
class ExampleVisitor : public RecursiveASTVisitor<ExampleVisitor> {
private:
ASTContext *astContext;
public:
explicit ExampleVisitor(CompilerInstance *CI, StringRef file)
: astContext(&(CI->getASTContext())) {}
virtual bool VisitVarDecl(VarDecl *d) {
std::cout << d->getNameAsString() << "@\n";
return true;
}
};
class ExampleASTConsumer : public ASTConsumer {
private:
ExampleVisitor visitor;
public:
explicit ExampleASTConsumer(CompilerInstance *CI, StringRef file)
: visitor(CI, file) {}
virtual void HandleTranslationUnit(ASTContext &Context) {
visitor.TraverseDecl(Context.getTranslationUnitDecl());
}
};
class DynamicIDHandler : public clang::ExternalSemaSource {
public:
DynamicIDHandler(clang::Sema *Sema)
: m_Sema(Sema), m_Context(Sema->getASTContext()) {}
~DynamicIDHandler() = default;
virtual bool LookupUnqualified(clang::LookupResult &R, clang::Scope *S) {
DeclarationName Name = R.getLookupName();
std::cout << Name.getAsString() << "\n";
return false;
}
private:
clang::Sema *m_Sema;
clang::ASTContext &m_Context;
};
LangOptions getFormattingLangOpts(bool Cpp03 = false) {
LangOptions LangOpts;
LangOpts.CPlusPlus = 1;
LangOpts.CPlusPlus11 = Cpp03 ? 0 : 1;
LangOpts.CPlusPlus14 = Cpp03 ? 0 : 1;
LangOpts.LineComment = 1;
LangOpts.Bool = 1;
LangOpts.ObjC1 = 1;
LangOpts.ObjC2 = 1;
return LangOpts;
}
int main() {
using clang::CompilerInstance;
using clang::TargetOptions;
using clang::TargetInfo;
using clang::FileEntry;
using clang::Token;
using clang::ASTContext;
using clang::ASTConsumer;
using clang::Parser;
using clang::DiagnosticOptions;
using clang::TextDiagnosticPrinter;
CompilerInstance ci;
ci.getLangOpts() = getFormattingLangOpts(false);
DiagnosticOptions diagnosticOptions;
ci.createDiagnostics();
std::shared_ptr<clang::TargetOptions> pto = std::make_shared<clang::TargetOptions>();
pto->Triple = llvm::sys::getDefaultTargetTriple();
TargetInfo *pti = TargetInfo::CreateTargetInfo(ci.getDiagnostics(), pto);
ci.setTarget(pti);
ci.createFileManager();
ci.createSourceManager(ci.getFileManager());
ci.createPreprocessor(clang::TU_Complete);
ci.getPreprocessorOpts().UsePredefines = false;
ci.createASTContext();
ci.setASTConsumer(
llvm::make_unique<ExampleASTConsumer>(&ci, "../src/test.cpp"));
ci.createSema(TU_Complete, nullptr);
auto &sema = ci.getSema();
sema.Initialize();
DynamicIDHandler handler(&sema);
sema.addExternalSource(&handler);
const FileEntry *pFile = ci.getFileManager().getFile("../src/test.cpp");
ci.getSourceManager().setMainFileID(ci.getSourceManager().createFileID(
pFile, clang::SourceLocation(), clang::SrcMgr::C_User));
ci.getDiagnosticClient().BeginSourceFile(ci.getLangOpts(),
&ci.getPreprocessor());
clang::ParseAST(sema,true,false);
ci.getDiagnosticClient().EndSourceFile();
return 0;
}
这个想法和 DynamicIDHandler 类来自于 cling 项目，其中未知符号为变量（因此有注释和代码）。
