From a006b80a74874fbc25e349dcb71462fc5f93aac7 Mon Sep 17 00:00:00 2001 From: Gabor Marton Date: Thu, 28 Feb 2019 15:24:59 +0000 Subject: [PATCH] [CTU] Do not allow different CPP dialects in CTU Summary: If CPP dialects are different then return with error. Consider this STL code: template struct __alloc_traits #if __cplusplus >= 201103L : std::allocator_traits<_Alloc> #endif { // ... }; This class template would create ODR errors during merging the two units, since in one translation unit the class template has a base class, however in the other unit it has none. Reviewers: xazax.hun, a_sidorin, r.stahl Subscribers: rnkovacs, dkrupp, Szelethus, gamesh411, cfe-commits Tags: #clang Differential Revision: https://reviews.llvm.org/D57906 llvm-svn: 355096 --- .../clang/CrossTU/CrossTranslationUnit.h | 3 ++- clang/lib/CrossTU/CrossTranslationUnit.cpp | 26 +++++++++++++++++++ 2 files changed, 28 insertions(+), 1 deletion(-) diff --git a/clang/include/clang/CrossTU/CrossTranslationUnit.h b/clang/include/clang/CrossTU/CrossTranslationUnit.h index 507cf2889d3a3..bbbba7ad7b447 100644 --- a/clang/include/clang/CrossTU/CrossTranslationUnit.h +++ b/clang/include/clang/CrossTU/CrossTranslationUnit.h @@ -43,7 +43,8 @@ enum class index_error_code { failed_to_get_external_ast, failed_to_generate_usr, triple_mismatch, - lang_mismatch + lang_mismatch, + lang_dialect_mismatch }; class IndexError : public llvm::ErrorInfo { diff --git a/clang/lib/CrossTU/CrossTranslationUnit.cpp b/clang/lib/CrossTU/CrossTranslationUnit.cpp index a0b83e92e25f8..04c98545ae543 100644 --- a/clang/lib/CrossTU/CrossTranslationUnit.cpp +++ b/clang/lib/CrossTU/CrossTranslationUnit.cpp @@ -42,6 +42,7 @@ STATISTIC(NumGetCTUSuccess, "requested function's body"); STATISTIC(NumTripleMismatch, "The # of triple mismatches"); STATISTIC(NumLangMismatch, "The # of language mismatches"); +STATISTIC(NumLangDialectMismatch, "The # of language dialect mismatches"); // Same as Triple's equality operator, but we check a field only if that is // known in both instances. @@ -99,6 +100,8 @@ class IndexErrorCategory : public std::error_category { return "Triple mismatch"; case index_error_code::lang_mismatch: return "Language mismatch"; + case index_error_code::lang_dialect_mismatch: + return "Language dialect mismatch"; } llvm_unreachable("Unrecognized index_error_code."); } @@ -228,6 +231,7 @@ CrossTranslationUnitContext::getCrossTUDefinition(const FunctionDecl *FD, const auto &LangTo = Context.getLangOpts(); const auto &LangFrom = Unit->getASTContext().getLangOpts(); + // FIXME: Currenty we do not support CTU across C++ and C and across // different dialects of C++. if (LangTo.CPlusPlus != LangFrom.CPlusPlus) { @@ -235,6 +239,28 @@ CrossTranslationUnitContext::getCrossTUDefinition(const FunctionDecl *FD, return llvm::make_error(index_error_code::lang_mismatch); } + // If CPP dialects are different then return with error. + // + // Consider this STL code: + // template + // struct __alloc_traits + // #if __cplusplus >= 201103L + // : std::allocator_traits<_Alloc> + // #endif + // { // ... + // }; + // This class template would create ODR errors during merging the two units, + // since in one translation unit the class template has a base class, however + // in the other unit it has none. + if (LangTo.CPlusPlus11 != LangFrom.CPlusPlus11 || + LangTo.CPlusPlus14 != LangFrom.CPlusPlus14 || + LangTo.CPlusPlus17 != LangFrom.CPlusPlus17 || + LangTo.CPlusPlus2a != LangFrom.CPlusPlus2a) { + ++NumLangDialectMismatch; + return llvm::make_error( + index_error_code::lang_dialect_mismatch); + } + TranslationUnitDecl *TU = Unit->getASTContext().getTranslationUnitDecl(); if (const FunctionDecl *ResultDecl = findFunctionInDeclContext(TU, LookupFnName))