diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 33ee8a53b5f37..9fdc8660a981e 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -629,6 +629,8 @@ Improvements to Clang's diagnostics #GH69470, #GH59391, #GH58172, #GH46215, #GH45915, #GH45891, #GH44490, #GH36703, #GH32903, #GH23312, #GH69874. +- Improve the diagnostics for placement new expression when const-qualified + object was passed as the storage argument. Improvements to Clang's time-trace ---------------------------------- diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td index 8fe7ad6138aa0..0bc1e7deff5ab 100644 --- a/clang/include/clang/Basic/DiagnosticSemaKinds.td +++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td @@ -8285,6 +8285,9 @@ def err_need_header_before_typeid : Error< def err_need_header_before_placement_new : Error< "no matching %0 function for non-allocating placement new expression; " "include ">; +def err_placement_new_into_const_qualified_storage : Error< + "placement new expression with a const-qualified argument of type %0 " + "is not allowed">; def err_ms___leave_not_in___try : Error< "'__leave' statement not in __try block">; def err_uuidof_without_guid : Error< diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp index ba52e8f8932d3..7367b906b70ba 100644 --- a/clang/lib/Sema/SemaExprCXX.cpp +++ b/clang/lib/Sema/SemaExprCXX.cpp @@ -2753,10 +2753,18 @@ static bool resolveAllocationOverloadInterior( if (Diagnose) { // If this is an allocation of the form 'new (p) X' for some object // pointer p (or an expression that will decay to such a pointer), - // diagnose the missing inclusion of . + // diagnose the reason for the error. if (!R.isClassLookup() && Args.size() == 2 && (Args[1]->getType()->isObjectPointerType() || Args[1]->getType()->isArrayType())) { + if (Args[1]->getType()->isPointerType()) { + if (Args[1]->getType()->getPointeeType().isConstQualified()) { + S.Diag(Args[1]->getExprLoc(), + diag::err_placement_new_into_const_qualified_storage) + << Args[1]->getType() << Args[1]->getSourceRange(); + return true; + } + } S.Diag(R.getNameLoc(), diag::err_need_header_before_placement_new) << R.getLookupName() << Range; // Listing the candidates is unlikely to be useful; skip it. diff --git a/clang/test/SemaCXX/new-delete.cpp b/clang/test/SemaCXX/new-delete.cpp index 9bbee32c58c36..fae9487cbe2c1 100644 --- a/clang/test/SemaCXX/new-delete.cpp +++ b/clang/test/SemaCXX/new-delete.cpp @@ -160,6 +160,13 @@ void bad_news(int *ip) #if __cplusplus < 201103L (void)new int[]{}; // expected-error {{array size must be specified in new expression with no initializer}} #endif + struct X { int n; }; + const X cx = {5}; + (void)new(&cx) X{10}; // expected-error {{placement new expression with a const-qualified argument of type 'const X *' is not allowed}} + const X* const cx2 = 0; + (void)new(cx2) X{10}; // expected-error {{placement new expression with a const-qualified argument of type 'const X *const' is not allowed}} + const int arr[1] = {1}; + (void)new(&arr[0]) int(10); // expected-error {{placement new expression with a const-qualified argument of type 'const int *' is not allowed}} } void no_matching_placement_new() {