Author: Utkarsh Saxena Date: 2022-08-18T10:30:40+02:00 New Revision: 0e0e8b65765e32776a5188e96d1672baeb11b16c
URL: https://github.com/llvm/llvm-project/commit/0e0e8b65765e32776a5188e96d1672baeb11b16c DIFF: https://github.com/llvm/llvm-project/commit/0e0e8b65765e32776a5188e96d1672baeb11b16c.diff LOG: Do not evaluate dependent immediate invocations We deferred the evaluation of dependent immediate invocations in https://reviews.llvm.org/D119375 until instantiation. We should also not consider them referenced from a non-consteval context. Fixes: https://github.com/llvm/llvm-project/issues/55601 ``` template<typename T> class Bar { consteval static T x() { return 5; } public: Bar() : a(x()) {} private: int a; }; Bar<int> g(); ``` Is now accepted by clang. Previously it errored with: `cannot take address of consteval function 'x' outside of an immediate invocation Bar() : a(x()) {}` Differential Revision: https://reviews.llvm.org/D132031 Added: Modified: clang/docs/ReleaseNotes.rst clang/lib/Sema/SemaExpr.cpp clang/test/SemaCXX/cxx2a-consteval.cpp Removed: ################################################################################ diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 4a6c9deb0c9c2..f74af34abea99 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -159,6 +159,8 @@ C++20 Feature Support template instantiation to be constexpr/consteval even though a call to such a function cannot appear in a constant expression. (C++14 [dcl.constexpr]p6 (CWG DR647/CWG DR1358)) +- Correctly defer dependent immediate function invocations until template instantiation. + This fixes `GH55601 <https://github.com/llvm/llvm-project/issues/55601>`_. diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp index 48a00f9de671c..377bfaa5f177d 100644 --- a/clang/lib/Sema/SemaExpr.cpp +++ b/clang/lib/Sema/SemaExpr.cpp @@ -19676,7 +19676,8 @@ void Sema::MarkDeclRefReferenced(DeclRefExpr *E, const Expr *Base) { if (auto *FD = dyn_cast<FunctionDecl>(E->getDecl())) if (!isUnevaluatedContext() && !isConstantEvaluated() && - FD->isConsteval() && !RebuildingImmediateInvocation) + FD->isConsteval() && !RebuildingImmediateInvocation && + !FD->isDependentContext()) ExprEvalContexts.back().ReferenceToConsteval.insert(E); MarkExprReferenced(*this, E->getLocation(), E->getDecl(), E, OdrUse, RefsMinusAssignments); diff --git a/clang/test/SemaCXX/cxx2a-consteval.cpp b/clang/test/SemaCXX/cxx2a-consteval.cpp index 4251d82c17e60..78011e2003417 100644 --- a/clang/test/SemaCXX/cxx2a-consteval.cpp +++ b/clang/test/SemaCXX/cxx2a-consteval.cpp @@ -648,9 +648,40 @@ template <typename T> constexpr int baz() { static_assert(bar<15>() == 15); static_assert(baz<int>() == sizeof(int)); - } // namespace value_dependent +// https://github.com/llvm/llvm-project/issues/55601 +namespace issue_55601 { +template<typename T> +class Bar { + consteval static T x() { return 5; } // expected-note {{non-constexpr constructor 'derp' cannot be used in a constant expression}} + public: + Bar() : a(x()) {} // expected-error {{call to consteval function 'issue_55601::Bar<issue_55601::derp>::x' is not a constant expression}} + // expected-error@-1 {{call to consteval function 'issue_55601::derp::operator int' is not a constant expression}} + // expected-note@-2 {{in call to 'x()'}} + // expected-note@-3 {{non-literal type 'issue_55601::derp' cannot be used in a constant expression}} + private: + int a; +}; +Bar<int> f; +Bar<float> g; + +struct derp { + // Can't be used in a constant expression + derp(int); // expected-note {{declared here}} + consteval operator int() const { return 5; } +}; +Bar<derp> a; // expected-note {{in instantiation of member function 'issue_55601::Bar<issue_55601::derp>::Bar' requested here}} + +struct constantDerp { + // Can be used in a constant expression. + consteval constantDerp(int) {} + consteval operator int() const { return 5; } +}; +Bar<constantDerp> b; + +} // namespace issue_55601 + namespace default_argument { // Previously calls of consteval functions in default arguments were rejected. _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
