Revert "[clang][SemaCXX] Diagnose tautological uses of consteval if and is_constant_evaluated"

This reverts commit 491b2810fb7fe5f080fa9c4f5945ed0a6909dc92.

This change broke valid code and generated incorrect diagnostics, see
https://reviews.llvm.org/D155064

1 files changed, 0 insertions, 42 deletions

diff --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp
index f5b4107..748b9d5 100644
--- a/clang/lib/Parse/ParseDecl.cpp
+++ b/clang/lib/Parse/ParseDecl.cpp
@@ -2461,15 +2461,6 @@ Decl *Parser::ParseDeclarationAfterDeclarator(
   return ParseDeclarationAfterDeclaratorAndAttributes(D, TemplateInfo);
 }
 
-/// Determine whether the given declaration is a global variable or
-/// static data member.
-static bool isNonlocalVariable(const Decl *D) {
-  if (const VarDecl *Var = dyn_cast_or_null<VarDecl>(D))
-    return Var->hasGlobalStorage();
-
-  return false;
-}
-
 Decl *Parser::ParseDeclarationAfterDeclaratorAndAttributes(
     Declarator &D, const ParsedTemplateInfo &TemplateInfo, ForRangeInit *FRI) {
   // RAII type used to track whether we're inside an initializer.
@@ -2502,36 +2493,6 @@ Decl *Parser::ParseDeclarationAfterDeclaratorAndAttributes(
       ThisDecl = nullptr;
     }
   };
-  struct EnterInitializerExpressionEvaluationContext {
-    Sema &S;
-    bool Entered;
-
-    EnterInitializerExpressionEvaluationContext(Sema &S, Declarator &D,
-                                                Decl *ThisDecl)
-        : S(S), Entered(false) {
-      if (ThisDecl && S.getLangOpts().CPlusPlus && !ThisDecl->isInvalidDecl()) {
-        Entered = true;
-        bool RuntimeEvaluated = S.ExprEvalContexts.back().IsRuntimeEvaluated;
-        Sema::ExpressionEvaluationContext NewEEC =
-            S.ExprEvalContexts.back().Context;
-        if ((D.getDeclSpec().getTypeQualifiers() == DeclSpec::TQ_const ||
-             isNonlocalVariable(ThisDecl)) &&
-            S.ExprEvalContexts.back().IsRuntimeEvaluated) {
-          RuntimeEvaluated = false;
-        }
-        if (D.getDeclSpec().hasConstexprSpecifier()) {
-          NewEEC = Sema::ExpressionEvaluationContext::ConstantEvaluated;
-          RuntimeEvaluated = false;
-        }
-        S.PushExpressionEvaluationContext(NewEEC, ThisDecl);
-        S.ExprEvalContexts.back().IsRuntimeEvaluated = RuntimeEvaluated;
-      }
-    }
-    ~EnterInitializerExpressionEvaluationContext() {
-      if (Entered)
-        S.PopExpressionEvaluationContext();
-    }
-  };
 
   enum class InitKind { Uninitialized, Equal, CXXDirect, CXXBraced };
   InitKind TheInitKind;
@@ -2631,7 +2592,6 @@ Decl *Parser::ParseDeclarationAfterDeclaratorAndAttributes(
             << getLangOpts().CPlusPlus20;
     } else {
       InitializerScopeRAII InitScope(*this, D, ThisDecl);
-      EnterInitializerExpressionEvaluationContext InitEC(Actions, D, ThisDecl);
 
       if (Tok.is(tok::code_completion)) {
         cutOffParsing();
@@ -2679,7 +2639,6 @@ Decl *Parser::ParseDeclarationAfterDeclaratorAndAttributes(
     ExprVector Exprs;
 
     InitializerScopeRAII InitScope(*this, D, ThisDecl);
-    EnterInitializerExpressionEvaluationContext InitEC(Actions, D, ThisDecl);
 
     auto ThisVarDecl = dyn_cast_or_null<VarDecl>(ThisDecl);
     auto RunSignatureHelp = [&]() {
@@ -2730,7 +2689,6 @@ Decl *Parser::ParseDeclarationAfterDeclaratorAndAttributes(
     Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists);
 
     InitializerScopeRAII InitScope(*this, D, ThisDecl);
-    EnterInitializerExpressionEvaluationContext InitEC(Actions, D, ThisDecl);
 
     PreferredType.enterVariableInit(Tok.getLocation(), ThisDecl);
     ExprResult Init(ParseBraceInitializer());