[clang] 2c4620c - [clang-repl] Consider the scope spec in template lookups for deduction guides.

[Vassil Vassilev via cfe-commits]

Author: Vassil Vassilev
Date: 2023-05-08T17:54:56Z
New Revision: 2c4620c1dadc032f968ce0aa835a441f268a8cdb

URL: https://github.com/llvm/llvm-project/commit/2c4620c1dadc032f968ce0aa835a441f268a8cdb
DIFF: https://github.com/llvm/llvm-project/commit/2c4620c1dadc032f968ce0aa835a441f268a8cdb.diff

LOG: [clang-repl] Consider the scope spec in template lookups for deduction guides.

isDeductionGuideName looks up the underlying template and if the template name
is qualified we miss that qualification resulting in an error. This issue
resurfaced in clang-repl where we call isDeductionGuideName more often to
distinguish between if we had a statement or declaration.

This patch passes the CXXScopeSpec information down to LookupTemplateName to
make the lookup more precise.

Differential revision: https://reviews.llvm.org/D147319

Added: 
    

Modified: 
    clang/include/clang/Sema/Sema.h
    clang/lib/Parse/ParseDecl.cpp
    clang/lib/Parse/ParseExprCXX.cpp
    clang/lib/Parse/ParseTentative.cpp
    clang/lib/Sema/SemaTemplate.cpp
    clang/test/Interpreter/disambiguate-decl-stmt.cpp

Removed: 
    


################################################################################
diff  --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index c6facd4e9e4af..e28ec936e4c2f 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -8081,7 +8081,7 @@ class Sema final {
   /// Determine whether a particular identifier might be the name in a C++1z
   /// deduction-guide declaration.
   bool isDeductionGuideName(Scope *S, const IdentifierInfo &Name,
-                            SourceLocation NameLoc,
+                            SourceLocation NameLoc, CXXScopeSpec &SS,
                             ParsedTemplateTy *Template = nullptr);
 
   bool DiagnoseUnknownTemplateName(const IdentifierInfo &II,

diff  --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp
index e28d609464123..2bbe2ba82139d 100644
--- a/clang/lib/Parse/ParseDecl.cpp
+++ b/clang/lib/Parse/ParseDecl.cpp
@@ -3696,11 +3696,12 @@ void Parser::ParseDeclarationSpecifiers(
 
       // Likewise, if this is a context where the identifier could be a template
       // name, check whether this is a deduction guide declaration.
+      CXXScopeSpec SS;
       if (getLangOpts().CPlusPlus17 &&
           (DSContext == DeclSpecContext::DSC_class ||
            DSContext == DeclSpecContext::DSC_top_level) &&
           Actions.isDeductionGuideName(getCurScope(), *Tok.getIdentifierInfo(),
-                                       Tok.getLocation()) &&
+                                       Tok.getLocation(), SS) &&
           isConstructorDeclarator(/*Unqualified*/ true,
                                   /*DeductionGuide*/ true))
         goto DoneWithDeclSpec;

diff  --git a/clang/lib/Parse/ParseExprCXX.cpp b/clang/lib/Parse/ParseExprCXX.cpp
index 8f56316cefcdf..123cf432b0969 100644
--- a/clang/lib/Parse/ParseExprCXX.cpp
+++ b/clang/lib/Parse/ParseExprCXX.cpp
@@ -2911,9 +2911,9 @@ bool Parser::ParseUnqualifiedId(CXXScopeSpec &SS, ParsedType ObjectType,
       if (!Ty)
         return true;
       Result.setConstructorName(Ty, IdLoc, IdLoc);
-    } else if (getLangOpts().CPlusPlus17 &&
-               AllowDeductionGuide && SS.isEmpty() &&
-               Actions.isDeductionGuideName(getCurScope(), *Id, IdLoc,
+    } else if (getLangOpts().CPlusPlus17 && AllowDeductionGuide &&
+               SS.isEmpty() &&
+               Actions.isDeductionGuideName(getCurScope(), *Id, IdLoc, SS,
                                             &TemplateName)) {
       // We have parsed a template-name naming a deduction guide.
       Result.setDeductionGuideName(TemplateName, IdLoc);

diff  --git a/clang/lib/Parse/ParseTentative.cpp b/clang/lib/Parse/ParseTentative.cpp
index 934087e59b809..02aa59ec6fa1f 100644
--- a/clang/lib/Parse/ParseTentative.cpp
+++ b/clang/lib/Parse/ParseTentative.cpp
@@ -74,9 +74,8 @@ bool Parser::isCXXDeclarationStatement(
       switch (Tok.getKind()) {
       case tok::identifier: {
         IdentifierInfo *II = Tok.getIdentifierInfo();
-        bool isDeductionGuide =
-            Actions.isDeductionGuideName(getCurScope(), *II, Tok.getLocation(),
-                                         /*Template=*/nullptr);
+        bool isDeductionGuide = Actions.isDeductionGuideName(
+            getCurScope(), *II, Tok.getLocation(), SS, /*Template=*/nullptr);
         if (Actions.isCurrentClassName(*II, getCurScope(), &SS) ||
             isDeductionGuide) {
           if (isConstructorDeclarator(/*Unqualified=*/SS.isEmpty(),

diff  --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index ca1b86c06097e..4fe4b9192ecd3 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -316,9 +316,8 @@ TemplateNameKind Sema::isTemplateName(Scope *S,
 }
 
 bool Sema::isDeductionGuideName(Scope *S, const IdentifierInfo &Name,
-                                SourceLocation NameLoc,
-                                ParsedTemplateTy *Template) {
-  CXXScopeSpec SS;
+                                SourceLocation NameLoc, CXXScopeSpec &SS,
+                                ParsedTemplateTy *Template /*=nullptr*/) {
   bool MemberOfUnknownSpecialization = false;
 
   // We could use redeclaration lookup here, but we don't need to: the

diff  --git a/clang/test/Interpreter/disambiguate-decl-stmt.cpp b/clang/test/Interpreter/disambiguate-decl-stmt.cpp
index 6f97310475980..85160b6d8a9bf 100644
--- a/clang/test/Interpreter/disambiguate-decl-stmt.cpp
+++ b/clang/test/Interpreter/disambiguate-decl-stmt.cpp
@@ -7,6 +7,10 @@ extern "C" int printf(const char*,...);
 
 // Decls which are hard to disambiguate
 
+// Templates
+namespace ns1 { template<typename T> void tmplt(T &) {}}
+int arg_tmplt = 12; ns1::tmplt(arg_tmplt);
+
 // ParseStatementOrDeclaration returns multiple statements.
 #ifdef MS
 int g_bFlag = 1;