[concepts] Fixes for gh72557

zyn0217 · Feb 4, 2024 · c04bb95 · c04bb95
1 parent 141de74
commit c04bb95
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Showing 3 changed files with 34 additions and 2 deletions.
diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
@@ -197,6 +197,9 @@ Bug Fixes to C++ Support
   Fixes (`#67976 <https://github.com/llvm/llvm-project/issues/67976>`_)
 - Fix crash and diagnostic with const qualified member operator new.
   Fixes (`#79748 <https://github.com/llvm/llvm-project/issues/79748>`_)
+- Fixed a crash where substituting into a requires-expression that involves parameter packs
+  during the equivalence determination of two constraint expressions.
+  (`#72557 <https://github.com/llvm/llvm-project/issues/72557>`_)
 
 Bug Fixes to AST Handling
 ^^^^^^^^^^^^^^^^^^^^^^^^^

diff --git a/clang/lib/Sema/SemaTemplateInstantiate.cpp b/clang/lib/Sema/SemaTemplateInstantiate.cpp
@@ -241,10 +241,21 @@ Response HandleFunctionTemplateDecl(const FunctionTemplateDecl *FTD,
 
     while (const Type *Ty = NNS ? NNS->getAsType() : nullptr) {
       if (NNS->isInstantiationDependent()) {
-        if (const auto *TSTy = Ty->getAs<TemplateSpecializationType>())
+        if (const auto *TSTy = Ty->getAs<TemplateSpecializationType>()) {
+          ArrayRef<TemplateArgument> Arguments = TSTy->template_arguments();
+          if (TSTy->isCurrentInstantiation()) {
+            auto *RD = TSTy->getCanonicalTypeInternal()->getAsCXXRecordDecl();
+            if (ClassTemplateDecl *CTD = RD->getDescribedClassTemplate())
+              Arguments = CTD->getInjectedTemplateArgs();
+            else if (auto *Specializtion =
+                         dyn_cast<ClassTemplateSpecializationDecl>(RD))
+              Arguments =
+                  Specializtion->getTemplateInstantiationArgs().asArray();
+          }
           Result.addOuterTemplateArguments(
-              const_cast<FunctionTemplateDecl *>(FTD), TSTy->template_arguments(),
+              const_cast<FunctionTemplateDecl *>(FTD), Arguments,
               /*Final=*/false);
+        }
       }
 
       NNS = NNS->getPrefix();

diff --git a/clang/test/SemaTemplate/concepts-out-of-line-def.cpp b/clang/test/SemaTemplate/concepts-out-of-line-def.cpp
@@ -581,3 +581,21 @@ void S<T>::test(T target, U... value)
   }
 {}
 } // namespace GH74447
+
+namespace GH72557 {
+
+template <typename...>
+concept IsAnyOf = true;
+
+template <class... DerTs> struct DerivedCollection {
+  template <class DerT>
+    requires IsAnyOf<DerTs...>
+  unsigned long index();
+};
+
+template <class... DerTs>
+template <class DerT>
+  requires IsAnyOf<DerTs...>
+unsigned long DerivedCollection<DerTs...>::index() {}
+
+} // namespace GH72557