Commit 5f967a72 authored by Hans Wennborg's avatar Hans Wennborg
Browse files

Merging r325576: 

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r325576 | hans | 2018-02-20 13:43:02 +0100 (Tue, 20 Feb 2018) | 13 lines

Revert r325375 "[MS] Make constexpr static data members implicitly inline"

This broke Clang bootstrap on Windows, PR36453.

> This handles them exactly the same way that we handle const integral
> static data members with inline definitions, which is what MSVC does.
>
> As a follow-up, now that we have a way to mark variables inline in the
> AST, we should consider marking them implicitly inline there instead of
> only treating them as inline in CodeGen. Unfortunately, this breaks a
> lot of dllimport test cases, so that is future work for now.
>
> Fixes PR36125.
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llvm-svn: 325577
parent 337d926f

clang/lib/AST/ASTContext.cpp

+1 −1
Original line number Diff line number Diff line
@@ -5854,7 +5854,7 @@ CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) const { 
bool ASTContext::isMSStaticDataMemberInlineDefinition(const VarDecl *VD) const {

  return getTargetInfo().getCXXABI().isMicrosoft() &&

         VD->isStaticDataMember() &&

         (VD->getType()->isIntegralOrEnumerationType() || VD->isConstexpr()) &&

         VD->getType()->isIntegralOrEnumerationType() &&

         !VD->getFirstDecl()->isOutOfLine() && VD->getFirstDecl()->hasInit();

}

clang/test/CodeGenCXX/static-data-member.cpp

+4 −36
Original line number Diff line number Diff line 
// RUN: %clang_cc1 -triple x86_64-pc-linux -std=c++14 -emit-llvm -o - %s | FileCheck %s

// RUN: %clang_cc1 -triple x86_64-apple-darwin -std=c++14 -emit-llvm -o - %s \

// RUN:     | FileCheck %s --check-prefix=MACHO

// RUN: %clang_cc1 -triple x86_64-pc-windows-msvc -std=c++14 -emit-llvm -o - %s \

// RUN:     | FileCheck %s --check-prefix=MSVC

// RUN: %clang_cc1 -triple x86_64-pc-windows-msvc -std=c++17 -emit-llvm -o - %s \

// RUN:     | FileCheck %s --check-prefix=MSVC

// RUN: %clang_cc1 -triple x86_64-pc-linux -emit-llvm -o - %s | FileCheck %s

// RUN: %clang_cc1 -triple x86_64-apple-darwin -emit-llvm -o - %s | \

// RUN: FileCheck --check-prefix=MACHO %s



// CHECK: @_ZN5test11A1aE = constant i32 10, align 4

// CHECK: @_ZN5test212_GLOBAL__N_11AIiE1xE = internal global i32 0, align 4
@@ -13,25 +9,12 @@ 
// MACHO: @_ZGVN5test31AIiE1xE = weak_odr global i64 0

// MACHO-NOT: comdat



// MSVC: @"\01?a@A@test1@@2HB" = linkonce_odr constant i32 10, comdat, align 4

// MSVC: @"\01?i@S@test1@@2HA" = external global i32

// MSVC: @"\01?x@?$A@H@?A@test2@@2HA" = internal global i32 0, align 4



// CHECK: _ZN5test51U2k0E = global i32 0

// CHECK: _ZN5test51U2k1E = global i32 0

// CHECK: _ZN5test51U2k2E = constant i32 76

// CHECK-NOT: test51U2k3E

// CHECK-NOT: test51U2k4E



// On Linux in C++14, neither of these are inline.

// CHECK: @_ZN16inline_constexpr1A10just_constE = available_externally constant i32 42

// CHECK: @_ZN16inline_constexpr1A10const_exprE = available_externally constant i32 43

//

// In MSVC, these are both implicitly inline regardless of the C++ standard

// version.

// MSVC: @"\01?just_const@A@inline_constexpr@@2HB" = linkonce_odr constant i32 42, comdat, align 4

// MSVC: @"\01?const_expr@A@inline_constexpr@@2HB" = linkonce_odr constant i32 43, comdat, align 4



// PR5564.

namespace test1 {

  struct A {
@@ -45,7 +28,7 @@ namespace test1 { 
  };



  void f() { 

    int a = *&A::a + S::i;

    int a = S::i;

  }

}
@@ -67,11 +50,6 @@ namespace test2 { 
  // CHECK:      [[TMP:%.*]] = call i32 @_ZN5test23fooEv()

  // CHECK-NEXT: store i32 [[TMP]], i32* @_ZN5test212_GLOBAL__N_11AIiE1xE, align 4

  // CHECK-NEXT: ret void



  // MSVC-LABEL: define internal void @"\01??__Ex@?$A@H@?A@test2@@2HA@YAXXZ"()

  // MSVC:      [[TMP:%.*]] = call i32 @"\01?foo@test2@@YAHXZ"()

  // MSVC-NEXT: store i32 [[TMP]], i32* @"\01?x@?$A@H@?A@test2@@2HA", align 4

  // MSVC-NEXT: ret void

}



// Test that we don't use threadsafe statics when initializing
@@ -130,13 +108,3 @@ namespace test5 { 
  // CHECK: store i32 {{.*}}, i32* @_ZN5test51U2k1E

  // CHECK-NOT: store {{.*}} i32* @_ZN5test51U2k2E

}
 


// Test that MSVC mode static constexpr data members are always inline, even pre

// C++17.

namespace inline_constexpr {

struct A {

  static const int just_const = 42;

  static constexpr int const_expr = 43;

};

int useit() { return *&A::just_const + *&A::const_expr; }

}