Revert r359949 "[clang] adding explicit(bool) from c++2a"

This caused Clang to start erroring on the following:

  struct S {
    template <typename = int> explicit S();
  };

  struct T : S {};

  struct U : T {
    U();
  };
  U::U() {}

  $ clang -c /tmp/x.cc
  /tmp/x.cc:10:4: error: call to implicitly-deleted default constructor of 'T'
  U::U() {}
     ^
  /tmp/x.cc:5:12: note: default constructor of 'T' is implicitly deleted
    because base class 'S' has no default constructor
  struct T : S {};
             ^
  1 error generated.

See discussion on the cfe-commits email thread.

This also reverts the follow-ups r359966 and r359968.

> this patch adds support for the explicit bool specifier.
>
> Changes:
> - The parsing for the explicit(bool) specifier was added in ParseDecl.cpp.
> - The storage of the explicit specifier was changed. the explicit specifier was stored as a boolean value in the FunctionDeclBitfields and in the DeclSpec class. now it is stored as a PointerIntPair<Expr*, 2> with a flag and a potential expression in CXXConstructorDecl, CXXDeductionGuideDecl, CXXConversionDecl and in the DeclSpec class.
> - Following the AST change, Serialization, ASTMatchers, ASTComparator and ASTPrinter were adapted.
> - Template instantiation was adapted to instantiate the potential expressions of the explicit(bool) specifier When instantiating their associated declaration.
> - The Add*Candidate functions were adapted, they now take a Boolean indicating if the context allowing explicit constructor or conversion function and this boolean is used to remove invalid overloads that required template instantiation to be detected.
> - Test for Semantic and Serialization were added.
>
> This patch is not yet complete. I still need to check that interaction with CTAD and deduction guides is correct. and add more tests for AST operations. But I wanted first feedback.
> Perhaps this patch should be spited in smaller patches, but making each patch testable as a standalone may be tricky.
>
> Patch by Tyker
>
> Differential Revision: https://reviews.llvm.org/D60934

llvm-svn: 360024

1 files changed, 9 insertions, 9 deletions

diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 86b5645d115..379e2aefb46 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -5705,7 +5705,7 @@ void Sema::DiagnoseFunctionSpecifiers(const DeclSpec &DS) {
     Diag(DS.getVirtualSpecLoc(),
          diag::err_virtual_non_function);
 
-  if (DS.hasExplicitSpecifier())
+  if (DS.isExplicitSpecified())
     Diag(DS.getExplicitSpecLoc(),
          diag::err_explicit_non_function);
 
@@ -7969,7 +7969,7 @@ static FunctionDecl* CreateNewFunctionDecl(Sema &SemaRef, Declarator &D,
     return NewFD;
   }
 
-  ExplicitSpecifier ExplicitSpecifier = D.getDeclSpec().getExplicitSpecifier();
+  bool isExplicit = D.getDeclSpec().isExplicitSpecified();
   bool isConstexpr = D.getDeclSpec().isConstexprSpecified();
 
   // Check that the return type is not an abstract class type.
@@ -7989,7 +7989,7 @@ static FunctionDecl* CreateNewFunctionDecl(Sema &SemaRef, Declarator &D,
     R = SemaRef.CheckConstructorDeclarator(D, R, SC);
     return CXXConstructorDecl::Create(
         SemaRef.Context, cast<CXXRecordDecl>(DC), D.getBeginLoc(), NameInfo, R,
-        TInfo, ExplicitSpecifier, isInline,
+        TInfo, isExplicit, isInline,
         /*isImplicitlyDeclared=*/false, isConstexpr);
 
   } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
@@ -8034,13 +8034,13 @@ static FunctionDecl* CreateNewFunctionDecl(Sema &SemaRef, Declarator &D,
     IsVirtualOkay = true;
     return CXXConversionDecl::Create(
         SemaRef.Context, cast<CXXRecordDecl>(DC), D.getBeginLoc(), NameInfo, R,
-        TInfo, isInline, ExplicitSpecifier, isConstexpr, SourceLocation());
+        TInfo, isInline, isExplicit, isConstexpr, SourceLocation());
 
   } else if (Name.getNameKind() == DeclarationName::CXXDeductionGuideName) {
     SemaRef.CheckDeductionGuideDeclarator(D, R, SC);
 
     return CXXDeductionGuideDecl::Create(SemaRef.Context, DC, D.getBeginLoc(),
-                                         ExplicitSpecifier, NameInfo, R, TInfo,
+                                         isExplicit, NameInfo, R, TInfo,
                                          D.getEndLoc());
   } else if (DC->isRecord()) {
     // If the name of the function is the same as the name of the record,
@@ -8401,7 +8401,7 @@ Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC,
   if (getLangOpts().CPlusPlus) {
     bool isInline = D.getDeclSpec().isInlineSpecified();
     bool isVirtual = D.getDeclSpec().isVirtualSpecified();
-    bool hasExplicit = D.getDeclSpec().hasExplicitSpecifier();
+    bool isExplicit = D.getDeclSpec().isExplicitSpecified();
     bool isConstexpr = D.getDeclSpec().isConstexprSpecified();
     isFriend = D.getDeclSpec().isFriendSpecified();
     if (isFriend && !isInline && D.isFunctionDefinition()) {
@@ -8584,20 +8584,20 @@ Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC,
     //  The explicit specifier shall be used only in the declaration of a
     //  constructor or conversion function within its class definition;
     //  see 12.3.1 and 12.3.2.
-    if (hasExplicit && !NewFD->isInvalidDecl() &&
+    if (isExplicit && !NewFD->isInvalidDecl() &&
         !isa<CXXDeductionGuideDecl>(NewFD)) {
       if (!CurContext->isRecord()) {
         // 'explicit' was specified outside of the class.
         Diag(D.getDeclSpec().getExplicitSpecLoc(),
              diag::err_explicit_out_of_class)
-            << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecRange());
+          << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc());
       } else if (!isa<CXXConstructorDecl>(NewFD) &&
                  !isa<CXXConversionDecl>(NewFD)) {
         // 'explicit' was specified on a function that wasn't a constructor
         // or conversion function.
         Diag(D.getDeclSpec().getExplicitSpecLoc(),
              diag::err_explicit_non_ctor_or_conv_function)
-            << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecRange());
+          << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc());
       }
     }