[CTU] Do not allow different CPP dialects in CTU
Summary:
If CPP dialects are different then return with error.
Consider this STL code:
template<typename _Alloc>
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
diff --git a/clang/lib/CrossTU/CrossTranslationUnit.cpp b/clang/lib/CrossTU/CrossTranslationUnit.cpp
index a0b83e9..04c9854 100644
--- a/clang/lib/CrossTU/CrossTranslationUnit.cpp
+++ b/clang/lib/CrossTU/CrossTranslationUnit.cpp
@@ -42,6 +42,7 @@
"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 @@
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 @@
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 @@
return llvm::make_error<IndexError>(index_error_code::lang_mismatch);
}
+ // If CPP dialects are different then return with error.
+ //
+ // Consider this STL code:
+ // template<typename _Alloc>
+ // 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<IndexError>(
+ index_error_code::lang_dialect_mismatch);
+ }
+
TranslationUnitDecl *TU = Unit->getASTContext().getTranslationUnitDecl();
if (const FunctionDecl *ResultDecl =
findFunctionInDeclContext(TU, LookupFnName))