diff options
| -rw-r--r-- | lib/Sema/SemaStmt.cpp | 8 | ||||
| -rw-r--r-- | test/SemaObjCXX/blocks.mm | 16 |
2 files changed, 20 insertions, 4 deletions
diff --git a/lib/Sema/SemaStmt.cpp b/lib/Sema/SemaStmt.cpp index a8832e9a1c..390e1b52c8 100644 --- a/lib/Sema/SemaStmt.cpp +++ b/lib/Sema/SemaStmt.cpp @@ -2743,15 +2743,17 @@ bool Sema::isCopyElisionCandidate(QualType ReturnType, const VarDecl *VD, // ...automatic... if (!VD->hasLocalStorage()) return false; + // Return false if VD is a __block variable. We don't want to implicitly move + // out of a __block variable during a return because we cannot assume the + // variable will no longer be used. + if (VD->hasAttr<BlocksAttr>()) return false; + if (AllowParamOrMoveConstructible) return true; // ...non-volatile... if (VD->getType().isVolatileQualified()) return false; - // __block variables can't be allocated in a way that permits NRVO. - if (VD->hasAttr<BlocksAttr>()) return false; - // Variables with higher required alignment than their type's ABI // alignment cannot use NRVO. if (!VD->getType()->isDependentType() && VD->hasAttr<AlignedAttr>() && diff --git a/test/SemaObjCXX/blocks.mm b/test/SemaObjCXX/blocks.mm index 09d614d372..3f901cc0a8 100644 --- a/test/SemaObjCXX/blocks.mm +++ b/test/SemaObjCXX/blocks.mm @@ -1,4 +1,4 @@ -// RUN: %clang_cc1 -fsyntax-only -verify -fblocks -Wno-objc-root-class %s +// RUN: %clang_cc1 -fsyntax-only -verify -fblocks -Wno-objc-root-class -std=c++11 %s @protocol NSObject; void bar(id(^)(void)); @@ -144,3 +144,17 @@ namespace DependentReturn { template void f<X>(X); } + +namespace MoveBlockVariable { +struct B0 { +}; + +struct B1 { // expected-note 2 {{candidate constructor (the implicit}} + B1(B0&&); // expected-note {{candidate constructor not viable}} +}; + +B1 test_move() { + __block B0 b; + return b; // expected-error {{no viable conversion from returned value of type 'MoveBlockVariable::B0' to function return type 'MoveBlockVariable::B1'}} +} +} |