[clang] Apply more missing changes from several Sema-related commits

macurtis-amd · macurtis-amd · commit 6b48a5aad152 · 2024-10-28T14:33:57.000-04:00
cherry-picked: 9e1f1cf sdkrystian@gmail.com Tue Jul 9 16:40:53 2024 -0400 [Clang][Sema] Handle class member access expressions with valid nested-name-specifiers that become invalid after lookup (llvm#98167) 584e431 sdkrystian@gmail.com Wed Jul 3 12:12:53 2024 -0400 [Clang][Sema] Treat explicit specializations of static data member templates declared without 'static' as static data members when diagnosing uses of 'auto' (llvm#97425) a1bce0b dblaikie@gmail.com Thu Jun 27 08:17:40 2024 -0700 Clang: Add warning flag for storage class specifiers on explicit specializations (llvm#96699) f46d146 erickvelez7@gmail.com Fri May 31 11:02:21 2024 -0700 [clang] require template arg list after template kw (llvm#80801) 033ec09 hanwei62@huawei.com Fri Dec 22 09:00:41 2023 +0800 [Clang][Sema] Fix Wswitch-default bad warning in template (llvm#76007) c281782 dongjianqiang2@huawei.com Thu Dec 7 09:03:15 2023 +0800 [clang][Sema] Add -Wswitch-default warning option (llvm#73077) Change-Id: Ib2582201b01cc62c3bf62011347925556e8531f7
diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
@@ -260,6 +260,9 @@ Resolutions to C++ Defect Reports
 - Reject explicit object parameters with type ``void`` (``this void``).
   (`CWG2915: Explicit object parameters of type void <https://cplusplus.github.io/CWG/issues/2915.html>`_).
 
+- Clang now requires a template argument list after a template keyword.
+  (`CWG96: Syntactic disambiguation using the template keyword <https://cplusplus.github.io/CWG/issues/96.html>`_).
+
 - Clang now allows trailing requires clause on explicit deduction guides.
   (`CWG2707: Deduction guides cannot have a trailing requires-clause <https://cplusplus.github.io/CWG/issues/2707.html>`_).
 
@@ -389,6 +392,9 @@ Attribute Changes in Clang
 Improvements to Clang's diagnostics
 -----------------------------------
 
+- Clang's ``-Wswitch-default`` flag now diagnoses whenever a ``switch`` statement
+  does not have a ``default`` label.
+
 - Some template related diagnostics have been improved.
 
   .. code-block:: c++
diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td
@@ -674,7 +674,7 @@ def ShadowAll : DiagGroup<"shadow-all", [Shadow, ShadowFieldInConstructor,
 
 def : DiagGroup<"sign-promo">;
 def SignCompare : DiagGroup<"sign-compare">;
-def : DiagGroup<"switch-default">;
+def SwitchDefault  : DiagGroup<"switch-default">;
 def : DiagGroup<"synth">;
 def SizeofArrayArgument : DiagGroup<"sizeof-array-argument">;
 def SizeofArrayDecay : DiagGroup<"sizeof-array-decay">;
diff --git a/clang/include/clang/Basic/DiagnosticParseKinds.td b/clang/include/clang/Basic/DiagnosticParseKinds.td
@@ -902,7 +902,6 @@ def err_requires_expr_in_simple_requirement : Error<
   "requires expression in requirement body; did "
   "you intend to place it in a nested requirement? (add another 'requires' "
   "before the expression)">;
-
 def missing_template_arg_list_after_template_kw : Extension<
   "a template argument list is expected after a name prefixed by the template "
   "keyword">, InGroup<DiagGroup<"missing-template-arg-list-after-template-kw">>,
diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -10348,6 +10348,8 @@ def warn_missing_case : Warning<"%plural{"
   "3:enumeration values %1, %2, and %3 not handled in switch|"
   ":%0 enumeration values not handled in switch: %1, %2, %3...}0">,
   InGroup<Switch>;
+def warn_switch_default : Warning<"'switch' missing 'default' label">,
+  InGroup<SwitchDefault>, DefaultIgnore;
 
 def warn_unannotated_fallthrough : Warning<
   "unannotated fall-through between switch labels">,
diff --git a/clang/lib/Parse/ParseExprCXX.cpp b/clang/lib/Parse/ParseExprCXX.cpp
@@ -14,6 +14,7 @@
 #include "clang/AST/DeclTemplate.h"
 #include "clang/AST/ExprCXX.h"
 #include "clang/Basic/PrettyStackTrace.h"
+#include "clang/Basic/TemplateKinds.h"
 #include "clang/Basic/TokenKinds.h"
 #include "clang/Lex/LiteralSupport.h"
 #include "clang/Parse/ParseDiagnostic.h"
@@ -3036,12 +3037,23 @@ bool Parser::ParseUnqualifiedId(CXXScopeSpec &SS, ParsedType ObjectType,
           SS, ObjectType, ObjectHadErrors,
           TemplateKWLoc ? *TemplateKWLoc : SourceLocation(), Id, IdLoc,
           EnteringContext, Result, TemplateSpecified);
-    else if (TemplateSpecified &&
-             Actions.ActOnTemplateName(
-                 getCurScope(), SS, *TemplateKWLoc, Result, ObjectType,
-                 EnteringContext, Template,
-                 /*AllowInjectedClassName*/ true) == TNK_Non_template)
-      return true;
+
+    if (TemplateSpecified) {
+      TemplateNameKind TNK =
+          Actions.ActOnTemplateName(getCurScope(), SS, *TemplateKWLoc, Result,
+                                    ObjectType, EnteringContext, Template,
+                                    /*AllowInjectedClassName=*/true);
+      if (TNK == TNK_Non_template)
+        return true;
+
+      // C++2c [tem.names]p6
+      // A name prefixed by the keyword template shall be followed by a template
+      // argument list or refer to a class template or an alias template.
+      if ((TNK == TNK_Function_template || TNK == TNK_Dependent_template_name ||
+           TNK == TNK_Var_template) &&
+          !Tok.is(tok::less))
+        Diag(IdLoc, diag::missing_template_arg_list_after_template_kw);
+    }
     return false;
   }
 
diff --git a/clang/lib/Sema/SemaExprMember.cpp b/clang/lib/Sema/SemaExprMember.cpp
@@ -790,9 +790,6 @@ ExprResult Sema::BuildMemberReferenceExpr(
     ActOnMemberAccessExtraArgs *ExtraArgs) {
   LookupResult R(*this, NameInfo, LookupMemberName);
 
-  if (SS.isInvalid())
-    return ExprError();
-
   // Implicit member accesses.
   if (!Base) {
     TypoExpr *TE = nullptr;
@@ -827,6 +824,11 @@ ExprResult Sema::BuildMemberReferenceExpr(
     BaseType = Base->getType();
   }
 
+  // BuildMemberReferenceExpr expects the nested-name-specifier, if any, to be
+  // valid.
+  if (SS.isInvalid())
+    return ExprError();
+
   return BuildMemberReferenceExpr(Base, BaseType,
                                   OpLoc, IsArrow, SS, TemplateKWLoc,
                                   FirstQualifierInScope, R, TemplateArgs, S,
@@ -1746,14 +1748,9 @@ static ExprResult LookupMemberExpr(Sema &S, LookupResult &R,
 
 ExprResult Sema::ActOnMemberAccessExpr(Scope *S, Expr *Base,
                                        SourceLocation OpLoc,
-                                       tok::TokenKind OpKind,
-                                       CXXScopeSpec &SS,
+                                       tok::TokenKind OpKind, CXXScopeSpec &SS,
                                        SourceLocation TemplateKWLoc,
-                                       UnqualifiedId &Id,
-                                       Decl *ObjCImpDecl) {
-  if (SS.isSet() && SS.isInvalid())
-    return ExprError();
-
+                                       UnqualifiedId &Id, Decl *ObjCImpDecl) {
   // Warn about the explicit constructor calls Microsoft extension.
   if (getLangOpts().MicrosoftExt &&
       Id.getKind() == UnqualifiedIdKind::IK_ConstructorName)
diff --git a/clang/lib/Sema/SemaStmt.cpp b/clang/lib/Sema/SemaStmt.cpp
@@ -1384,10 +1384,7 @@ Sema::ActOnFinishSwitchStmt(SourceLocation SwitchLoc, Stmt *Switch,
       assert(!HasConstantCond ||
              (ConstantCondValue.getBitWidth() == CondWidth &&
               ConstantCondValue.isSigned() == CondIsSigned));
-#if NEEDS_PATCH_FOR_SWITCH
-//[clang][Sema] Add -Wswitch-default warning option (#73077)
       Diag(SwitchLoc, diag::warn_switch_default);
-#endif
     }
     bool ShouldCheckConstantCond = HasConstantCond;
 
diff --git a/clang/lib/Sema/SemaType.cpp b/clang/lib/Sema/SemaType.cpp
@@ -3224,8 +3224,7 @@ static QualType GetDeclSpecTypeForDeclarator(TypeProcessingState &state,
       break;
     }
     case DeclaratorContext::Member: {
-      if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_static ||
-          D.isFunctionDeclarator())
+      if (D.isStaticMember() || D.isFunctionDeclarator())
         break;
       bool Cxx = SemaRef.getLangOpts().CPlusPlus;
       if (isa<ObjCContainerDecl>(SemaRef.CurContext)) {
diff --git a/clang/test/CXX/basic/basic.lookup/basic.lookup.qual/basic.lookup.qual.general/p2.cpp b/clang/test/CXX/basic/basic.lookup/basic.lookup.qual/basic.lookup.qual.general/p2.cpp
@@ -0,0 +1,16 @@
+// RUN: %clang_cc1 -verify -Wno-unused %s
+
+struct A {
+  int y;
+};
+
+struct B; // expected-note 4{{forward declaration of 'B'}}
+
+void f(A *a, B *b) {
+  a->B::x; // expected-error {{incomplete type 'B' named in nested name specifier}}
+  a->A::x; // expected-error {{no member named 'x' in 'A'}}
+  a->A::y;
+  b->B::x; // expected-error {{member access into incomplete type 'B'}}
+  b->A::x; // expected-error {{member access into incomplete type 'B'}}
+  b->A::y; // expected-error {{member access into incomplete type 'B'}}
+}
diff --git a/clang/test/CXX/dcl.dcl/dcl.spec/dcl.stc/p1.cpp b/clang/test/CXX/dcl.dcl/dcl.spec/dcl.stc/p1.cpp
@@ -1,4 +1,5 @@
-// RUN: %clang_cc1 -fsyntax-only -verify %s
+// RUN: %clang_cc1 -fsyntax-only -verify=expected,spec %s
+// RUN: %clang_cc1 -fsyntax-only -verify -Wno-explicit-specialization-storage-class %s
 
 // A storage-class-specifier shall not be specified in an explicit
 // specialization (14.7.3) or an explicit instantiation (14.7.2)
@@ -7,13 +8,13 @@ template<typename T> void f(T) {}
 template<typename T> static void g(T) {}
 
 
-template<> static void f<int>(int); // expected-warning{{explicit specialization cannot have a storage class}}
+template<> static void f<int>(int); // spec-warning{{explicit specialization cannot have a storage class}}
 template static void f<float>(float); // expected-error{{explicit instantiation cannot have a storage class}}
 
 template<> void f<double>(double);
 template void f<long>(long);
 
-template<> static void g<int>(int); // expected-warning{{explicit specialization cannot have a storage class}}
+template<> static void g<int>(int); // spec-warning{{explicit specialization cannot have a storage class}}
 template static void g<float>(float); // expected-error{{explicit instantiation cannot have a storage class}}
 
 template<> void g<double>(double);
@@ -29,5 +30,12 @@ int X<T>::value = 17;
 
 template static int X<int>::value; // expected-error{{explicit instantiation cannot have a storage class}}
 
-template<> static int X<float>::value; // expected-warning{{explicit specialization cannot have a storage class}}
+template<> static int X<float>::value; // spec-warning{{explicit specialization cannot have a storage class}}
                                        // expected-error@-1{{'static' can only be specified inside the class definition}}
+
+struct t1 {
+  template<typename>
+  static void f1();
+  template<>
+  static void f1<int>(); // spec-warning{{explicit specialization cannot have a storage class}}
+};
diff --git a/clang/test/CXX/dcl.dcl/dcl.spec/dcl.type/dcl.spec.auto/p5-cxx14.cpp b/clang/test/CXX/dcl.dcl/dcl.spec/dcl.type/dcl.spec.auto/p5-cxx14.cpp
@@ -0,0 +1,12 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s -std=c++14
+
+struct A {
+  template<int N>
+  static constexpr auto x = N;
+
+  template<>
+  constexpr auto x<1> = 1;
+
+  template<>
+  static constexpr auto x<2> = 2; // expected-warning{{explicit specialization cannot have a storage class}}
+};
diff --git a/clang/test/CXX/drs/cwg0xx.cpp b/clang/test/CXX/drs/cwg0xx.cpp
@@ -1404,7 +1404,7 @@ namespace cwg95 { // cwg95: 3.3
   //   expected-note@#cwg95-C-f {{implicitly declared private here}}
 }
 
-namespace cwg96 { // cwg96: no
+namespace cwg96 { // cwg96: sup P1787
   struct A {
     void f(int);
     template<typename T> int f(T);
@@ -1419,6 +1419,7 @@ namespace cwg96 { // cwg96: no
     // name a class template.
     // FIXME: What about alias templates?
     int k2 = a.template f(1);
+    // expected-error@-1 {{a template argument list is expected after a name prefixed by the template keyword}}
     A::template S<int> s;
     B<A::template S> b;
   }
diff --git a/clang/test/Sema/switch-default.cpp b/clang/test/Sema/switch-default.cpp
@@ -1,7 +1,5 @@
 // RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 -Wswitch-default %s
 
-// XFAIL: *
-
 int f1(int a) {
   switch (a) {                // expected-warning {{'switch' missing 'default' label}}
     case 1: a++; break;
@@ -52,4 +50,3 @@ int t2(Index i)
 int main() {
   return t1(1);       // expected-note {{in instantiation of function template specialization 't1<int>' requested here}}
 }
-
diff --git a/clang/test/SemaCXX/cxx1y-variable-templates_in_class.cpp b/clang/test/SemaCXX/cxx1y-variable-templates_in_class.cpp
@@ -1,7 +1,7 @@
 // RUN: %clang_cc1 -triple %itanium_abi_triple -std=c++98 -verify -fsyntax-only %s -Wno-c++11-extensions -Wno-c++1y-extensions -DPRECXX11
 // RUN: %clang_cc1 -triple %itanium_abi_triple -std=c++11 -verify -fsyntax-only -Wno-c++1y-extensions %s
 // RUN: %clang_cc1 -triple %itanium_abi_triple -std=c++1y -verify -fsyntax-only %s -DCPP1Y
-// XFAIL: *
+
 #define CONST const
 
 #ifdef PRECXX11
diff --git a/clang/test/SemaCXX/template-specialization.cpp b/clang/test/SemaCXX/template-specialization.cpp
@@ -11,7 +11,7 @@ struct B {
   template <int i>
   static void foo() {
     int array[i];
-    A::template bar(array[0]); // expected-error {{no matching function for call to 'bar'}}
+    A::template bar(array[0]); // expected-error {{a template argument list is expected after a name prefixed by the template keyword}} expected-error {{no matching function for call to 'bar'}}
   }
 };
 
diff --git a/clang/test/SemaCXX/warn-explicit-specialization-storage-class.cpp b/clang/test/SemaCXX/warn-explicit-specialization-storage-class.cpp
@@ -0,0 +1,18 @@
+// RUN: %clang_cc1 -triple i686-pc-linux-gnu -fsyntax-only -verify %s
+// RUN: %clang_cc1 -triple i686-pc-linux-gnu -fsyntax-only -Wno-explicit-specialization-storage-class -verify=expnone %s
+
+// expnone-no-diagnostics
+
+struct A {
+    template<typename T>
+    static constexpr int x = 0;
+
+    template<>
+    static constexpr int x<void> = 1; // expected-warning{{explicit specialization cannot have a storage class}}
+};
+
+template<typename T>
+static constexpr int x = 0;
+
+template<>
+static constexpr int x<void> = 1; // expected-warning{{explicit specialization cannot have a storage class}}
diff --git a/clang/test/SemaTemplate/dependent-names.cpp b/clang/test/SemaTemplate/dependent-names.cpp
@@ -420,7 +420,7 @@ template <typename> struct CT2 {
 template <typename T> int CT2<int>::X<>; // expected-error {{template parameter list matching the non-templated nested type 'CT2<int>' should be empty}}
 
 namespace DependentTemplateIdWithNoArgs {
-  template<typename T> void f() { T::template f(); }
+  template<typename T> void f() { T::template f(); } // expected-error {{a template argument list is expected after a name prefixed by the template keyword}}
   struct X {
     template<int = 0> static void f();
   };
@@ -431,7 +431,7 @@ namespace DependentUnresolvedUsingTemplate {
   template<typename T>
   struct X : T {
     using T::foo;
-    void f() { this->template foo(); } // expected-error {{does not refer to a template}}
+    void f() { this->template foo(); } // expected-error {{does not refer to a template}} expected-error {{a template argument list is expected after a name prefixed by the template keyword}}
     void g() { this->template foo<>(); } // expected-error {{does not refer to a template}}
     void h() { this->template foo<int>(); } // expected-error {{does not refer to a template}}
   };
@@ -450,7 +450,7 @@ namespace DependentUnresolvedUsingTemplate {
 namespace PR37680 {
   template <class a> struct b : a {
     using a::add;
-    template<int> int add() { return this->template add(0); }
+    template<int> int add() { return this->template add(0); } // expected-error {{a template argument list is expected after a name prefixed by the template keyword}}
   };
   struct a {
     template<typename T = void> int add(...);
diff --git a/clang/test/SemaTemplate/template-id-expr.cpp b/clang/test/SemaTemplate/template-id-expr.cpp
diff --git a/clang/test/SemaTemplate/template-id-printing.cpp b/clang/test/SemaTemplate/template-id-printing.cpp
diff --git a/clang/www/cxx_dr_status.html b/clang/www/cxx_dr_status.html
