The 'constexpr implies const' rule for non-static member functions is gone in
C++1y, so stop adding the 'const' there. Provide a compatibility warning for
code relying on this in C++11, with a fix-it hint. Update our lazily-written
tests to add the const, except for those ones which were testing our
implementation of this rule.
llvm-svn: 179969
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index c20b5ff..6ecc84f 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -6726,9 +6726,12 @@
//
// This needs to be delayed until we know whether this is an out-of-line
// definition of a static member function.
+ //
+ // This rule is not present in C++1y, so we produce a backwards
+ // compatibility warning whenever it happens in C++11.
CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
- if (MD && MD->isConstexpr() && !MD->isStatic() &&
- !isa<CXXConstructorDecl>(MD) &&
+ if (!getLangOpts().CPlusPlus1y && MD && MD->isConstexpr() &&
+ !MD->isStatic() && !isa<CXXConstructorDecl>(MD) &&
(MD->getTypeQualifiers() & Qualifiers::Const) == 0) {
CXXMethodDecl *OldMD = dyn_cast_or_null<CXXMethodDecl>(OldDecl);
if (FunctionTemplateDecl *OldTD =
@@ -6743,6 +6746,18 @@
ArrayRef<QualType>(FPT->arg_type_begin(),
FPT->getNumArgs()),
EPI));
+
+ // Warn that we did this, if we're not performing template instantiation.
+ // In that case, we'll have warned already when the template was defined.
+ if (ActiveTemplateInstantiations.empty()) {
+ SourceLocation AddConstLoc;
+ if (FunctionTypeLoc FTL = MD->getTypeSourceInfo()->getTypeLoc()
+ .IgnoreParens().getAs<FunctionTypeLoc>())
+ AddConstLoc = PP.getLocForEndOfToken(FTL.getRParenLoc());
+
+ Diag(MD->getLocation(), diag::warn_cxx1y_compat_constexpr_not_const)
+ << FixItHint::CreateInsertion(AddConstLoc, " const");
+ }
}
}