Author: ericwf Date: Thu Oct 25 11:16:16 2018 New Revision: 345296 URL: http://llvm.org/viewvc/llvm-project?rev=345296&view=rev Log: [SemaCXX] Unconfuse Clang when std::align_val_t is unscoped in C++03
Summary: When -faligned-allocation is specified in C++03 libc++ defines std::align_val_t as an unscoped enumeration type (because Clang didn't provide scoped enumerations as an extension until 8.0). Unfortunately Clang confuses the `align_val_t` overloads of delete with the sized deallocation overloads which aren't enabled. This caused Clang to call the aligned deallocation function as if it were the sized deallocation overload. For example: https://godbolt.org/z/xXJELh This patch fixes the confusion. Reviewers: rsmith, EricWF Reviewed By: EricWF Subscribers: cfe-commits Differential Revision: https://reviews.llvm.org/D53508 Added: cfe/trunk/test/SemaCXX/cxx03-aligned-allocation-unscoped-enum.cpp Modified: cfe/trunk/lib/Sema/SemaExprCXX.cpp Modified: cfe/trunk/lib/Sema/SemaExprCXX.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaExprCXX.cpp?rev=345296&r1=345295&r2=345296&view=diff ============================================================================== --- cfe/trunk/lib/Sema/SemaExprCXX.cpp (original) +++ cfe/trunk/lib/Sema/SemaExprCXX.cpp Thu Oct 25 11:16:16 2018 @@ -1515,8 +1515,11 @@ namespace { if (FD->getNumParams() == NumBaseParams + 2) HasAlignValT = HasSizeT = true; else if (FD->getNumParams() == NumBaseParams + 1) { - HasSizeT = FD->getParamDecl(NumBaseParams)->getType()->isIntegerType(); - HasAlignValT = !HasSizeT; + QualType ParamTy = FD->getParamDecl(NumBaseParams)->getType(); + HasAlignValT = ParamTy->isAlignValT(); + HasSizeT = !HasAlignValT; + assert((HasAlignValT || ParamTy->isIntegerType()) && + "Candidate is not regular dealloc function"); } // In CUDA, determine how much we'd like / dislike to call this. Added: cfe/trunk/test/SemaCXX/cxx03-aligned-allocation-unscoped-enum.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/cxx03-aligned-allocation-unscoped-enum.cpp?rev=345296&view=auto ============================================================================== --- cfe/trunk/test/SemaCXX/cxx03-aligned-allocation-unscoped-enum.cpp (added) +++ cfe/trunk/test/SemaCXX/cxx03-aligned-allocation-unscoped-enum.cpp Thu Oct 25 11:16:16 2018 @@ -0,0 +1,21 @@ +// RUN: %clang_cc1 -std=c++03 -triple x86_64-pc-linux-gnu %s \ +// RUN: -faligned-allocation -emit-llvm -o - | FileCheck %s + +// Ensure Clang doesn't confuse std::align_val_t with the sized deallocation +// parameter when the enum type is unscoped. Libc++ does this in C++03 in order +// to support aligned allocation in that dialect. + +using size_t = __decltype(sizeof(0)); + +namespace std { +enum align_val_t { zero = size_t(0), + max = size_t(-1) }; +} + +// CHECK-LABEL: define void @_Z1fPi( +void f(int *p) { + // CHECK-NOT: call void @_ZdlPvSt11align_val_t( + // CHECK: call void @_ZdlPv( + // CHECK: ret void + delete p; +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
