r300262 - PR32185: Revert r291512 and add a testcase for PR32185.
Richard Smith via cfe-commits
cfe-commits at lists.llvm.org
Thu Apr 13 14:37:24 PDT 2017
Author: rsmith
Date: Thu Apr 13 16:37:24 2017
New Revision: 300262
URL: http://llvm.org/viewvc/llvm-project?rev=300262&view=rev
Log:
PR32185: Revert r291512 and add a testcase for PR32185.
This reverts an attempt to check that types match when matching a
dependently-typed non-type template parameter. (This comes up when matching the
parameters of a template template parameter against the parameters of a
template template argument.)
The matching rules here are murky at best. Our behavior after this revert is
definitely wrong for certain C++17 features (for 'auto' template parameter
types within the parameter list of a template template argument in particular),
but our behavior before this revert is wrong for some pre-existing testcases,
so reverting to our prior behavior seems like our best option.
Modified:
cfe/trunk/lib/Sema/SemaTemplate.cpp
cfe/trunk/test/Modules/cxx-templates.cpp
cfe/trunk/test/SemaCXX/cxx1z-class-template-argument-deduction.cpp
cfe/trunk/test/SemaTemplate/deduction.cpp
cfe/trunk/test/SemaTemplate/temp_arg_template.cpp
cfe/trunk/test/SemaTemplate/temp_arg_template_cxx1z.cpp
Modified: cfe/trunk/lib/Sema/SemaTemplate.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaTemplate.cpp?rev=300262&r1=300261&r2=300262&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaTemplate.cpp (original)
+++ cfe/trunk/lib/Sema/SemaTemplate.cpp Thu Apr 13 16:37:24 2017
@@ -2109,7 +2109,6 @@ struct DependencyChecker : RecursiveASTV
typedef RecursiveASTVisitor<DependencyChecker> super;
unsigned Depth;
- bool FindLessThanDepth;
// Whether we're looking for a use of a template parameter that makes the
// overall construct type-dependent / a dependent type. This is strictly
@@ -2120,16 +2119,25 @@ struct DependencyChecker : RecursiveASTV
bool Match;
SourceLocation MatchLoc;
- DependencyChecker(unsigned Depth, bool IgnoreNonTypeDependent,
- bool FindLessThanDepth = false)
- : Depth(Depth), FindLessThanDepth(FindLessThanDepth),
- IgnoreNonTypeDependent(IgnoreNonTypeDependent), Match(false) {}
+ DependencyChecker(unsigned Depth, bool IgnoreNonTypeDependent)
+ : Depth(Depth), IgnoreNonTypeDependent(IgnoreNonTypeDependent),
+ Match(false) {}
DependencyChecker(TemplateParameterList *Params, bool IgnoreNonTypeDependent)
- : DependencyChecker(Params->getDepth(), IgnoreNonTypeDependent) {}
+ : IgnoreNonTypeDependent(IgnoreNonTypeDependent), Match(false) {
+ NamedDecl *ND = Params->getParam(0);
+ if (TemplateTypeParmDecl *PD = dyn_cast<TemplateTypeParmDecl>(ND)) {
+ Depth = PD->getDepth();
+ } else if (NonTypeTemplateParmDecl *PD =
+ dyn_cast<NonTypeTemplateParmDecl>(ND)) {
+ Depth = PD->getDepth();
+ } else {
+ Depth = cast<TemplateTemplateParmDecl>(ND)->getDepth();
+ }
+ }
bool Matches(unsigned ParmDepth, SourceLocation Loc = SourceLocation()) {
- if (FindLessThanDepth ^ (ParmDepth >= Depth)) {
+ if (ParmDepth >= Depth) {
Match = true;
MatchLoc = Loc;
return true;
@@ -6432,15 +6440,6 @@ Sema::BuildExpressionFromIntegralTemplat
return E;
}
-static bool isDependentOnOuter(NonTypeTemplateParmDecl *NTTP) {
- if (NTTP->getDepth() == 0 || !NTTP->getType()->isDependentType())
- return false;
- DependencyChecker Checker(NTTP->getDepth(), /*IgnoreNonTypeDependent*/ false,
- /*FindLessThanDepth*/ true);
- Checker.TraverseType(NTTP->getType());
- return Checker.Match;
-}
-
/// \brief Match two template parameters within template parameter lists.
static bool MatchTemplateParameterKind(Sema &S, NamedDecl *New, NamedDecl *Old,
bool Complain,
@@ -6497,10 +6496,11 @@ static bool MatchTemplateParameterKind(S
// If we are matching a template template argument to a template
// template parameter and one of the non-type template parameter types
- // is dependent on an outer template's parameter, then we must wait until
- // template instantiation time to actually compare the arguments.
+ // is dependent, then we must wait until template instantiation time
+ // to actually compare the arguments.
if (Kind == Sema::TPL_TemplateTemplateArgumentMatch &&
- (isDependentOnOuter(OldNTTP) || isDependentOnOuter(NewNTTP)))
+ (OldNTTP->getType()->isDependentType() ||
+ NewNTTP->getType()->isDependentType()))
return true;
if (!S.Context.hasSameType(OldNTTP->getType(), NewNTTP->getType())) {
Modified: cfe/trunk/test/Modules/cxx-templates.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Modules/cxx-templates.cpp?rev=300262&r1=300261&r2=300262&view=diff
==============================================================================
--- cfe/trunk/test/Modules/cxx-templates.cpp (original)
+++ cfe/trunk/test/Modules/cxx-templates.cpp Thu Apr 13 16:37:24 2017
@@ -49,8 +49,14 @@ void g() {
// expected-note at Inputs/cxx-templates-a.h:11 {{candidate}}
// expected-note at Inputs/cxx-templates-b.h:11 {{candidate}}
- template_param_kinds_3<Tmpl_T_T_A>();
- template_param_kinds_3<Tmpl_T_T_B>();
+ // FIXME: This should be valid, but we incorrectly match the template template
+ // argument against both template template parameters.
+ template_param_kinds_3<Tmpl_T_T_A>(); // expected-error {{ambiguous}}
+ // expected-note at Inputs/cxx-templates-a.h:12 {{candidate}}
+ // expected-note at Inputs/cxx-templates-b.h:12 {{candidate}}
+ template_param_kinds_3<Tmpl_T_T_B>(); // expected-error {{ambiguous}}
+ // expected-note at Inputs/cxx-templates-a.h:12 {{candidate}}
+ // expected-note at Inputs/cxx-templates-b.h:12 {{candidate}}
// Trigger the instantiation of a template in 'a' that uses a type defined in
// 'common'. That type is not visible here.
Modified: cfe/trunk/test/SemaCXX/cxx1z-class-template-argument-deduction.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/cxx1z-class-template-argument-deduction.cpp?rev=300262&r1=300261&r2=300262&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/cxx1z-class-template-argument-deduction.cpp (original)
+++ cfe/trunk/test/SemaCXX/cxx1z-class-template-argument-deduction.cpp Thu Apr 13 16:37:24 2017
@@ -179,9 +179,9 @@ namespace default_args_from_ctor {
namespace transform_params {
template<typename T, T N, template<T (*v)[N]> typename U, T (*X)[N]>
- struct A { // expected-note 2{{candidate}}
+ struct A {
template<typename V, V M, V (*Y)[M], template<V (*v)[M]> typename W>
- A(U<X>, W<Y>); // expected-note {{[with V = int, M = 12, Y = &transform_params::n]}}
+ A(U<X>, W<Y>);
static constexpr T v = N;
};
@@ -189,9 +189,7 @@ namespace transform_params {
int n[12];
template<int (*)[12]> struct Q {};
Q<&n> qn;
- // FIXME: The class template argument deduction result here is correct, but
- // we incorrectly fail to deduce arguments for the constructor!
- A a(qn, qn); // expected-error {{no matching constructor for initialization of 'transform_params::A<int, 12, Q, &transform_params::n>'}}
+ A a(qn, qn);
static_assert(a.v == 12);
template<typename ...T> struct B {
@@ -203,16 +201,12 @@ namespace transform_params {
};
B b({1, 2, 3}, "foo", {'x', 'y', 'z', 'w'}); // ok
- // This should be accepted once -std=c++1z implies
- // -frelaxed-template-template-args. Without that, a template template
- // parameter 'template<int, int, int> typename' cannot bind to a template
- // template argument 'template<int...> typename'.
- template<typename ...T> struct C { // expected-note {{candidate}}
+ template<typename ...T> struct C {
template<T ...V, template<T...> typename X>
- C(X<V...>); // expected-note {{substitution failure [with T = <int, int, int>, V = <0, 1, 2>]}}
+ C(X<V...>);
};
template<int...> struct Y {};
- C c(Y<0, 1, 2>{}); // expected-error {{no viable constructor or deduction guide}}
+ C c(Y<0, 1, 2>{});
template<typename ...T> struct D {
template<T ...V> D(Y<V...>);
Modified: cfe/trunk/test/SemaTemplate/deduction.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaTemplate/deduction.cpp?rev=300262&r1=300261&r2=300262&view=diff
==============================================================================
--- cfe/trunk/test/SemaTemplate/deduction.cpp (original)
+++ cfe/trunk/test/SemaTemplate/deduction.cpp Thu Apr 13 16:37:24 2017
@@ -483,16 +483,15 @@ namespace check_extended_pack {
}
namespace dependent_template_template_param_non_type_param_type {
- template<int N> struct A { // expected-note 2{{candidate}}
+ template<int N> struct A {
template<typename V = int, V M = 12, V (*Y)[M], template<V (*v)[M]> class W>
- A(W<Y>); // expected-note {{[with V = int, M = 12, Y = &dependent_template_template_param_non_type_param_type::n]}}
+ A(W<Y>);
};
int n[12];
template<int (*)[12]> struct Q {};
Q<&n> qn;
- // FIXME: This should be accepted, but we somehow fail to deduce W.
- A<0> a(qn); // expected-error {{no matching constructor for initialization}}
+ A<0> a(qn);
}
namespace dependent_list_deduction {
Modified: cfe/trunk/test/SemaTemplate/temp_arg_template.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaTemplate/temp_arg_template.cpp?rev=300262&r1=300261&r2=300262&view=diff
==============================================================================
--- cfe/trunk/test/SemaTemplate/temp_arg_template.cpp (original)
+++ cfe/trunk/test/SemaTemplate/temp_arg_template.cpp Thu Apr 13 16:37:24 2017
@@ -102,7 +102,42 @@ void foo() {
}
namespace CheckDependentNonTypeParamTypes {
- template<template<typename T, typename U, T v> class> struct A {}; // expected-note {{previous}}
- template<typename T, typename U, U v> struct B {}; // expected-note {{different type}}
- A<B> ab; // expected-error {{different template parameters}}
+ template<template<typename T, typename U, T v> class X> struct A {
+ void f() {
+ X<int, void*, 3> x; // expected-error {{does not refer to any declaration}}
+ }
+ void g() {
+ X<int, long, 3> x;
+ }
+ void h() {
+ // FIXME: If we accept A<B> at all, it's not obvious what should happen
+ // here. While parsing the template, we form
+ // X<unsigned char, int, (unsigned char)1234>
+ // but in the final instantiation do we get
+ // B<unsigned char, int, (int)1234>
+ // or
+ // B<unsigned char, int, (int)(unsigned char)1234>
+ // ?
+ X<unsigned char, int, 1234> x;
+ int check[x.value == 1234 ? 1 : -1];
+ }
+ };
+
+ template<typename T, typename U, U v> struct B { // expected-note {{parameter}}
+ static const U value = v;
+ };
+
+ // FIXME: This should probably be rejected, but the rules are at best unclear.
+ A<B> ab;
+
+ void use() {
+ ab.f(); // expected-note {{instantiation of}}
+ ab.g();
+ ab.h();
+ }
+}
+
+namespace PR32185 {
+ template<template<typename T, T> class U> struct A {};
+ template<template<typename T, T> class U> struct B : A<U> {};
}
Modified: cfe/trunk/test/SemaTemplate/temp_arg_template_cxx1z.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaTemplate/temp_arg_template_cxx1z.cpp?rev=300262&r1=300261&r2=300262&view=diff
==============================================================================
--- cfe/trunk/test/SemaTemplate/temp_arg_template_cxx1z.cpp (original)
+++ cfe/trunk/test/SemaTemplate/temp_arg_template_cxx1z.cpp Thu Apr 13 16:37:24 2017
@@ -78,7 +78,7 @@ namespace Auto {
template<int*> struct IntPtr;
TInt<Auto> ia;
- TInt<AutoPtr> iap; // expected-error {{different template parameters}}
+ TInt<AutoPtr> iap; // FIXME: ill-formed (?)
TInt<DecltypeAuto> ida;
TInt<Int> ii;
TInt<IntPtr> iip; // expected-error {{different template parameters}}
@@ -90,18 +90,18 @@ namespace Auto {
TIntPtr<IntPtr> ipip;
TAuto<Auto> aa;
- TAuto<AutoPtr> aap; // expected-error {{different template parameters}}
- TAuto<Int> ai; // expected-error {{different template parameters}}
- TAuto<IntPtr> aip; // expected-error {{different template parameters}}
+ TAuto<AutoPtr> aap; // FIXME: ill-formed (?)
+ TAuto<Int> ai; // FIXME: ill-formed (?)
+ TAuto<IntPtr> aip; // FIXME: ill-formed (?)
TAutoPtr<Auto> apa;
TAutoPtr<AutoPtr> apap;
- TAutoPtr<Int> api; // expected-error {{different template parameters}}
- TAutoPtr<IntPtr> apip; // expected-error {{different template parameters}}
+ TAutoPtr<Int> api; // FIXME: ill-formed (?)
+ TAutoPtr<IntPtr> apip; // FIXME: ill-formed (?)
TDecltypeAuto<DecltypeAuto> dada;
- TDecltypeAuto<Int> dai; // expected-error {{different template parameters}}
- TDecltypeAuto<IntPtr> daip; // expected-error {{different template parameters}}
+ TDecltypeAuto<Int> dai; // FIXME: ill-formed (?)
+ TDecltypeAuto<IntPtr> daip; // FIXME: ill-formed (?)
// FIXME: It's completely unclear what should happen here, but these results
// seem at least plausible:
@@ -111,7 +111,7 @@ namespace Auto {
// parameters (such as 'user-defined-type &') that are not valid 'auto'
// parameters.
TDecltypeAuto<Auto> daa;
- TDecltypeAuto<AutoPtr> daa; // expected-error {{different template parameters}}
+ TDecltypeAuto<AutoPtr> daap; // FIXME: should probably be ill-formed
int n;
template<auto A, decltype(A) B = &n> struct SubstFailure;
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