我认为另一种解决方案更适合 OP 而不是模糊解析。
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以获取有关此符号的一些信息。通过这个，你可以实现你想要的。
这是一个如何设置它的快速示例。它并不完全起作用（我没有在LookupUnqualified方法中做任何事情），您可能需要做进一步的调查，我认为这是一个好的开始。
// Declares clang::SyntaxOnlyAction.
#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) {
// de cette façon, on applique le visiteur sur l'ensemble de la translation
// unit
visitor.TraverseDecl(Context.getTranslationUnitDecl());
}
};
class DynamicIDHandler : public clang::ExternalSemaSource {
public:
DynamicIDHandler(clang::Sema *Sema)
: m_Sema(Sema), m_Context(Sema->getASTContext()) {}
~DynamicIDHandler() = default;
/// \brief Provides last resort lookup for failed unqualified lookups
///
/// If there is failed lookup, tell sema to create an artificial declaration
/// which is of dependent type. So the lookup result is marked as dependent
/// and the diagnostics are suppressed. After that is's an interpreter's
/// responsibility to fix all these fake declarations and lookups.
/// It is done by the DynamicExprTransformer.
///
/// @param[out] R The recovered symbol.
/// @param[in] S The scope in which the lookup failed.
virtual bool LookupUnqualified(clang::LookupResult &R, clang::Scope *S) {
DeclarationName Name = R.getLookupName();
std::cout << Name.getAsString() << "\n";
// IdentifierInfo *II = Name.getAsIdentifierInfo();
// SourceLocation Loc = R.getNameLoc();
// VarDecl *Result =
// // VarDecl::Create(m_Context, R.getSema().getFunctionLevelDeclContext(),
// // Loc, Loc, II, m_Context.DependentTy,
// // /*TypeSourceInfo*/ 0, SC_None, SC_None);
// if (Result) {
// R.addDecl(Result);
// // Say that we can handle the situation. Clang should try to recover
// return true;
// } else{
// return false;
// }
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类来自未知符号是可变的项目（因此是注释和代码）。