On Tue, Jan 8, 2013 at 3:47 PM, Richard Smith <[email protected]> wrote: > On Tue, Jan 8, 2013 at 3:29 PM, Eli Friedman <[email protected]> wrote: >> On Tue, Jan 8, 2013 at 3:17 PM, Fariborz Jahanian <[email protected]> >> wrote: >>> Author: fjahanian >>> Date: Tue Jan 8 17:17:51 2013 >>> New Revision: 171912 >>> >>> URL: http://llvm.org/viewvc/llvm-project?rev=171912&view=rev >>> Log: >>> objectiveC blocks: It is impractical to capture >>> struct variables with flexiable array members in >>> blocks (and lambdas). Issue error instead of >>> crashing in IRGen. // rdar://12655829 >>> >>> Added: >>> cfe/trunk/test/SemaObjCXX/capturing-flexible-array-in-block.mm >>> Modified: >>> cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td >>> cfe/trunk/lib/Sema/SemaExpr.cpp >>> >>> Modified: cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td?rev=171912&r1=171911&r2=171912&view=diff >>> ============================================================================== >>> --- cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td (original) >>> +++ cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td Tue Jan 8 >>> 17:17:51 2013 >>> @@ -4224,6 +4224,9 @@ >>> def err_ref_non_value : Error<"%0 does not refer to a value">; >>> def err_ref_vm_type : Error< >>> "cannot refer to declaration with a variably modified type inside >>> block">; >>> +def err_ref_flexarray_type : Error< >>> + "cannot refer to declaration of structure variable with flexible array >>> member " >>> + "inside block">; >>> def err_ref_array_type : Error< >>> "cannot refer to declaration with an array type inside block">; >>> def err_property_not_found : Error< >>> @@ -4609,6 +4612,9 @@ >>> def err_lambda_capture_vm_type : Error< >>> "variable %0 with variably modified type cannot be captured in " >>> "a lambda expression">; >>> + def err_lambda_capture_flexarray_type : Error< >>> + "variable %0 with flexible array member cannot be captured in " >>> + "a lambda expression">; >>> def err_lambda_impcap : Error< >>> "variable %0 cannot be implicitly captured in a lambda with no " >>> "capture-default specified">; >>> >>> Modified: cfe/trunk/lib/Sema/SemaExpr.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaExpr.cpp?rev=171912&r1=171911&r2=171912&view=diff >>> ============================================================================== >>> --- cfe/trunk/lib/Sema/SemaExpr.cpp (original) >>> +++ cfe/trunk/lib/Sema/SemaExpr.cpp Tue Jan 8 17:17:51 2013 >>> @@ -10759,7 +10759,22 @@ >>> } >>> return true; >>> } >>> - >>> + // Prohibit prohibit structs with flexisble array members too. >>> + // We cannot capture what is in the tail end of the struct. >>> + if (const RecordType *VTTy = Var->getType()->getAs<RecordType>()) { >>> + if (VTTy->getDecl()->hasFlexibleArrayMember()) { >>> + if (BuildAndDiagnose) { >>> + if (IsBlock) >>> + Diag(Loc, diag::err_ref_flexarray_type); >>> + else >>> + Diag(Loc, diag::err_lambda_capture_flexarray_type) >>> + << Var->getDeclName(); >>> + Diag(Var->getLocation(), diag::note_previous_decl) >>> + << Var->getDeclName(); >>> + } >>> + return true; >>> + } >>> + } >>> // Lambdas are not allowed to capture __block variables; they don't >>> // support the expected semantics. >>> if (IsLambda && HasBlocksAttr) { >>> >>> Added: cfe/trunk/test/SemaObjCXX/capturing-flexible-array-in-block.mm >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaObjCXX/capturing-flexible-array-in-block.mm?rev=171912&view=auto >>> ============================================================================== >>> --- cfe/trunk/test/SemaObjCXX/capturing-flexible-array-in-block.mm (added) >>> +++ cfe/trunk/test/SemaObjCXX/capturing-flexible-array-in-block.mm Tue Jan >>> 8 17:17:51 2013 >>> @@ -0,0 +1,9 @@ >>> +// RUN: %clang_cc1 -fsyntax-only -fblocks -verify -std=c++11 %s >>> +// rdar://12655829 >>> + >>> +void f() { >>> + struct { int x; int y[]; } a; // expected-note 2 {{'a' declared here}} >>> + ^{return a.x;}(); // expected-error {{cannot refer to declaration of >>> structure variable with flexible array member inside block}} >>> + >>> + [] {return a.x;}(); // expected-error {{variable 'a' with flexible array >>> member cannot be captured in a lambda expression}} >>> +} >> >> We can do whatever we want with blocks, but the C++11 standard doesn't >> allow us to reject this construct for lambda expressions. > > C++11 doesn't have flexible array members. The diagnostic seems > sensible to me for lambdas.
Oh, oops... clang is missing a diagnostic here. -Eli _______________________________________________ cfe-commits mailing list [email protected] http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
