diff options
| -rw-r--r-- | clang/include/clang/Basic/DiagnosticGroups.td | 2 | ||||
| -rw-r--r-- | clang/include/clang/Basic/DiagnosticSemaKinds.td | 5 | ||||
| -rw-r--r-- | clang/lib/Sema/SemaLambda.cpp | 11 | ||||
| -rw-r--r-- | clang/test/SemaCXX/cxx2a-lambda-equals-this.cpp | 12 |
4 files changed, 28 insertions, 2 deletions
diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td index a7fe5032dff..e021cf69758 100644 --- a/clang/include/clang/Basic/DiagnosticGroups.td +++ b/clang/include/clang/Basic/DiagnosticGroups.td @@ -120,6 +120,7 @@ def DeprecatedDynamicExceptionSpec def DeprecatedImplementations :DiagGroup<"deprecated-implementations">; def DeprecatedIncrementBool : DiagGroup<"deprecated-increment-bool">; def DeprecatedRegister : DiagGroup<"deprecated-register">; +def DeprecatedThisCapture : DiagGroup<"deprecated-this-capture">; def DeprecatedWritableStr : DiagGroup<"deprecated-writable-strings", [CXX11CompatDeprecatedWritableStr]>; // FIXME: Why is DeprecatedImplementations not in this group? @@ -128,6 +129,7 @@ def Deprecated : DiagGroup<"deprecated", [DeprecatedAttributes, DeprecatedDynamicExceptionSpec, DeprecatedIncrementBool, DeprecatedRegister, + DeprecatedThisCapture, DeprecatedWritableStr]>, DiagCategory<"Deprecations">; diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td index c02e7d27806..0f1ce0e1203 100644 --- a/clang/include/clang/Basic/DiagnosticSemaKinds.td +++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td @@ -6545,6 +6545,11 @@ let CategoryName = "Lambda Issue" in { def ext_equals_this_lambda_capture_cxx2a : ExtWarn< "explicit capture of 'this' with a capture default of '=' " "is a C++2a extension">, InGroup<CXX2a>; + def warn_deprecated_this_capture : Warning< + "implicit capture of 'this' with a capture default of '=' is deprecated">, + InGroup<DeprecatedThisCapture>, DefaultIgnore; + def note_deprecated_this_capture : Note< + "add an explicit capture of 'this' to capture '*this' by reference">; } def err_return_in_captured_stmt : Error< diff --git a/clang/lib/Sema/SemaLambda.cpp b/clang/lib/Sema/SemaLambda.cpp index fcacc2a17c9..5e69feceda6 100644 --- a/clang/lib/Sema/SemaLambda.cpp +++ b/clang/lib/Sema/SemaLambda.cpp @@ -1548,6 +1548,17 @@ ExprResult Sema::BuildLambdaExpr(SourceLocation StartLoc, SourceLocation EndLoc, // Handle 'this' capture. if (From.isThisCapture()) { + // Capturing 'this' implicitly with a default of '[=]' is deprecated, + // because it results in a reference capture. Don't warn prior to + // C++2a; there's nothing that can be done about it before then. + if (getLangOpts().CPlusPlus2a && IsImplicit && + CaptureDefault == LCD_ByCopy) { + Diag(From.getLocation(), diag::warn_deprecated_this_capture); + Diag(CaptureDefaultLoc, diag::note_deprecated_this_capture) + << FixItHint::CreateInsertion( + getLocForEndOfToken(CaptureDefaultLoc), ", this"); + } + Captures.push_back( LambdaCapture(From.getLocation(), IsImplicit, From.isCopyCapture() ? LCK_StarThis : LCK_This)); diff --git a/clang/test/SemaCXX/cxx2a-lambda-equals-this.cpp b/clang/test/SemaCXX/cxx2a-lambda-equals-this.cpp index ce6916322e5..652fb8da9b6 100644 --- a/clang/test/SemaCXX/cxx2a-lambda-equals-this.cpp +++ b/clang/test/SemaCXX/cxx2a-lambda-equals-this.cpp @@ -1,5 +1,4 @@ -// RUN: %clang_cc1 -std=c++2a -verify %s -// expected-no-diagnostics +// RUN: %clang_cc1 -std=c++2a -verify %s -Wdeprecated // This test does two things. // Deleting the copy constructor ensures that an [=, this] capture doesn't copy the object. @@ -13,3 +12,12 @@ class A { L(); } }; + +struct B { + int i; + void f() { + (void) [=] { // expected-note {{add an explicit capture of 'this'}} + return i; // expected-warning {{implicit capture of 'this' with a capture default of '=' is deprecated}} + }; + } +}; |
