Author: tstellar Date: Wed May 30 11:19:45 2018 New Revision: 333571 URL: http://llvm.org/viewvc/llvm-project?rev=333571&view=rev Log: Merging r326476:
------------------------------------------------------------------------ r326476 | mstorsjo | 2018-03-01 12:22:57 -0800 (Thu, 01 Mar 2018) | 7 lines [RecordLayout] Only assert that fundamental type sizes are power of two on MSVC Make types with sizes that aren't a power of two an error (that can be disabled) in structs with ms_struct layout, except on mingw where the situation is quite likely to occur and GCC handles it silently. Differential Revision: https://reviews.llvm.org/D43908 ------------------------------------------------------------------------ Added: cfe/branches/release_60/test/CodeGen/ms_struct-long-double.c Modified: cfe/branches/release_60/include/clang/Basic/DiagnosticSemaKinds.td cfe/branches/release_60/lib/AST/RecordLayoutBuilder.cpp Modified: cfe/branches/release_60/include/clang/Basic/DiagnosticSemaKinds.td URL: http://llvm.org/viewvc/llvm-project/cfe/branches/release_60/include/clang/Basic/DiagnosticSemaKinds.td?rev=333571&r1=333570&r2=333571&view=diff ============================================================================== --- cfe/branches/release_60/include/clang/Basic/DiagnosticSemaKinds.td (original) +++ cfe/branches/release_60/include/clang/Basic/DiagnosticSemaKinds.td Wed May 30 11:19:45 2018 @@ -759,6 +759,10 @@ def warn_cxx_ms_struct : Warning<"ms_struct may not produce Microsoft-compatible layouts for classes " "with base classes or virtual functions">, DefaultError, InGroup<IncompatibleMSStruct>; +def warn_npot_ms_struct : + Warning<"ms_struct may not produce Microsoft-compatible layouts with fundamental " + "data types with sizes that aren't a power of two">, + DefaultError, InGroup<IncompatibleMSStruct>; def err_section_conflict : Error<"%0 causes a section type conflict with %1">; def err_no_base_classes : Error<"invalid use of '__super', %0 has no base classes">; def err_invalid_super_scope : Error<"invalid use of '__super', " Modified: cfe/branches/release_60/lib/AST/RecordLayoutBuilder.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/branches/release_60/lib/AST/RecordLayoutBuilder.cpp?rev=333571&r1=333570&r2=333571&view=diff ============================================================================== --- cfe/branches/release_60/lib/AST/RecordLayoutBuilder.cpp (original) +++ cfe/branches/release_60/lib/AST/RecordLayoutBuilder.cpp Wed May 30 11:19:45 2018 @@ -1751,10 +1751,32 @@ void ItaniumRecordLayoutBuilder::LayoutF QualType T = Context.getBaseElementType(D->getType()); if (const BuiltinType *BTy = T->getAs<BuiltinType>()) { CharUnits TypeSize = Context.getTypeSizeInChars(BTy); - assert( - (llvm::isPowerOf2_64(TypeSize.getQuantity()) || - Context.getTargetInfo().getTriple().isWindowsGNUEnvironment()) && - "Non PowerOf2 size outside of GNU mode"); + + if (!llvm::isPowerOf2_64(TypeSize.getQuantity())) { + assert( + !Context.getTargetInfo().getTriple().isWindowsMSVCEnvironment() && + "Non PowerOf2 size in MSVC mode"); + // Base types with sizes that aren't a power of two don't work + // with the layout rules for MS structs. This isn't an issue in + // MSVC itself since there are no such base data types there. + // On e.g. x86_32 mingw and linux, long double is 12 bytes though. + // Any structs involving that data type obviously can't be ABI + // compatible with MSVC regardless of how it is laid out. + + // Since ms_struct can be mass enabled (via a pragma or via the + // -mms-bitfields command line parameter), this can trigger for + // structs that don't actually need MSVC compatibility, so we + // need to be able to sidestep the ms_struct layout for these types. + + // Since the combination of -mms-bitfields together with structs + // like max_align_t (which contains a long double) for mingw is + // quite comon (and GCC handles it silently), just handle it + // silently there. For other targets that have ms_struct enabled + // (most probably via a pragma or attribute), trigger a diagnostic + // that defaults to an error. + if (!Context.getTargetInfo().getTriple().isWindowsGNUEnvironment()) + Diag(D->getLocation(), diag::warn_npot_ms_struct); + } if (TypeSize > FieldAlign && llvm::isPowerOf2_64(TypeSize.getQuantity())) FieldAlign = TypeSize; Added: cfe/branches/release_60/test/CodeGen/ms_struct-long-double.c URL: http://llvm.org/viewvc/llvm-project/cfe/branches/release_60/test/CodeGen/ms_struct-long-double.c?rev=333571&view=auto ============================================================================== --- cfe/branches/release_60/test/CodeGen/ms_struct-long-double.c (added) +++ cfe/branches/release_60/test/CodeGen/ms_struct-long-double.c Wed May 30 11:19:45 2018 @@ -0,0 +1,17 @@ +// RUN: %clang_cc1 -emit-llvm-only -triple i686-windows-gnu -fdump-record-layouts %s | FileCheck %s +// RUN: %clang_cc1 -emit-llvm-only -triple i686-linux -fdump-record-layouts -Wno-incompatible-ms-struct %s | FileCheck %s +// RUN: not %clang_cc1 -emit-llvm-only -triple i686-linux -fdump-record-layouts %s 2>&1 | FileCheck %s -check-prefix=ERROR + +struct ldb_struct { + char c; + long double ldb; +} __attribute__((__ms_struct__)); + +struct ldb_struct a; + +// CHECK: 0 | struct ldb_struct +// CHECK-NEXT: 0 | char c +// CHECK-NEXT: 4 | long double ldb +// CHECK-NEXT: | [sizeof=16, align=4] + +// ERROR: error: ms_struct may not produce Microsoft-compatible layouts with fundamental data types with sizes that aren't a power of two _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits