Commit c5b1e744 authored by Hans Wennborg's avatar Hans Wennborg
Browse files

Merging r228792: 

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r228792 | rsmith | 2015-02-10 18:41:33 -0800 (Tue, 10 Feb 2015) | 5 lines

Add a warning for direct-list-initialization of a variable with a deduced type
(or of a lambda init-capture, which is sort-of such a variable). The semantics
of such constructs will change when we implement N3922, so we intend to warn on
this in Clang 3.6 then change the semantics in Clang 3.7.

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llvm-svn: 228799
parent fece094b

clang/include/clang/Basic/DiagnosticGroups.td

+3 −0
Original line number Diff line number Diff line
@@ -749,3 +749,6 @@ def SerializedDiagnostics : DiagGroup<"serialized-diagnostics">; 
// A warning group for warnings about code that clang accepts when

// compiling CUDA C/C++ but which is not compatible with the CUDA spec.

def CudaCompat : DiagGroup<"cuda-compat">;



// A warning group for things that will change semantics in the future.

def FutureCompat : DiagGroup<"future-compat">;

clang/include/clang/Basic/DiagnosticParseKinds.td

+4 −0
Original line number Diff line number Diff line
@@ -802,6 +802,10 @@ def warn_cxx98_compat_lambda : Warning< 
def err_lambda_missing_parens : Error<

  "lambda requires '()' before %select{'mutable'|return type|"

  "attribute specifier}0">;

def warn_init_capture_direct_list_init : Warning<

  "direct list initialization of a lambda init-capture will change meaning in "

  "a future version of Clang; insert an '=' to avoid a change in behavior">,

  InGroup<FutureCompat>;



// Availability attribute

def err_expected_version : Error<

clang/include/clang/Basic/DiagnosticSemaKinds.td

+4 −0
Original line number Diff line number Diff line
@@ -1635,6 +1635,10 @@ def err_auto_var_init_multiple_expressions : Error< 
def err_auto_var_init_paren_braces : Error<

  "cannot deduce type for variable %0 with type %1 from "

  "parenthesized initializer list">;

def warn_auto_var_direct_list_init : Warning<

  "direct list initialization of a variable with a deduced type will change "

  "meaning in a future version of Clang; insert an '=' to avoid a change in "

  "behavior">, InGroup<FutureCompat>;

def err_auto_new_ctor_multiple_expressions : Error<

  "new expression for type %0 contains multiple constructor arguments">;

def err_auto_missing_trailing_return : Error<

clang/lib/Parse/ParseExprCXX.cpp

+8 −3
Original line number Diff line number Diff line
@@ -894,11 +894,16 @@ Optional<unsigned> Parser::ParseLambdaIntroducer(LambdaIntroducer &Intro, 
        // to save the necessary state, and restore it later.

        EnterExpressionEvaluationContext EC(Actions,

                                            Sema::PotentiallyEvaluated);

        TryConsumeToken(tok::equal);

        bool HadEquals = TryConsumeToken(tok::equal);



        if (!SkippedInits)

        if (!SkippedInits) {

          // Warn on constructs that will change meaning when we implement N3922

          if (!HadEquals && Tok.is(tok::l_brace)) {

            Diag(Tok, diag::warn_init_capture_direct_list_init)

              << FixItHint::CreateInsertion(Tok.getLocation(), "=");

          }

          Init = ParseInitializer();

        else if (Tok.is(tok::l_brace)) {

        } else if (Tok.is(tok::l_brace)) {

          BalancedDelimiterTracker Braces(*this, tok::l_brace);

          Braces.consumeOpen();

          Braces.skipToEnd();

clang/lib/Sema/SemaDecl.cpp

+8 −0
Original line number Diff line number Diff line
@@ -8702,6 +8702,14 @@ void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, 
    CheckVariableDeclarationType(VDecl);

    if (VDecl->isInvalidDecl())

      return;













    // If all looks well, warn if this is a case that will change meaning when













    // we implement N3922.













    if (DirectInit && !CXXDirectInit && isa<InitListExpr>(Init)) {













      Diag(Init->getLocStart(),













           diag::warn_auto_var_direct_list_init)













        << FixItHint::CreateInsertion(Init->getLocStart(), "=");













    }















  }





























  // dllimport cannot be used on variable definitions.