Check and build conversion sequences for non-type template arguments in
dependent contexts when processing the template in C++11 and C++14, just like
we do in C++98 and C++1z. This allows us to diagnose invalid templates earlier.
llvm-svn: 290567
diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp
index 6da0768..47e3df2 100644
--- a/clang/lib/Sema/SemaOverload.cpp
+++ b/clang/lib/Sema/SemaOverload.cpp
@@ -5382,7 +5382,7 @@
APValue V;
auto R = ::CheckConvertedConstantExpression(*this, From, T, V, CCE, true);
- if (!R.isInvalid())
+ if (!R.isInvalid() && !R.get()->isValueDependent())
Value = V.getInt();
return R;
}
diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index 87667f2..83146af 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -5076,8 +5076,8 @@
// For a value-dependent argument, CheckConvertedConstantExpression is
// permitted (and expected) to be unable to determine a value.
if (ArgResult.get()->isValueDependent()) {
- Converted = TemplateArgument(Arg);
- return Arg;
+ Converted = TemplateArgument(ArgResult.get());
+ return ArgResult;
}
QualType CanonParamType = Context.getCanonicalType(ParamType);
@@ -5184,14 +5184,6 @@
// conversions (4.7) are applied.
if (getLangOpts().CPlusPlus11) {
- // We can't check arbitrary value-dependent arguments.
- // FIXME: If there's no viable conversion to the template parameter type,
- // we should be able to diagnose that prior to instantiation.
- if (Arg->isValueDependent()) {
- Converted = TemplateArgument(Arg);
- return Arg;
- }
-
// C++ [temp.arg.nontype]p1:
// A template-argument for a non-type, non-template template-parameter
// shall be one of:
@@ -5206,6 +5198,12 @@
if (ArgResult.isInvalid())
return ExprError();
+ // We can't check arbitrary value-dependent arguments.
+ if (ArgResult.get()->isValueDependent()) {
+ Converted = TemplateArgument(ArgResult.get());
+ return ArgResult;
+ }
+
// Widen the argument value to sizeof(parameter type). This is almost
// always a no-op, except when the parameter type is bool. In
// that case, this may extend the argument from 1 bit to 8 bits.
diff --git a/clang/test/SemaTemplate/temp_arg_nontype_cxx11.cpp b/clang/test/SemaTemplate/temp_arg_nontype_cxx11.cpp
index aa4cc8c..17e5253 100644
--- a/clang/test/SemaTemplate/temp_arg_nontype_cxx11.cpp
+++ b/clang/test/SemaTemplate/temp_arg_nontype_cxx11.cpp
@@ -27,3 +27,12 @@
namespace Auto {
template<auto> struct A { }; // expected-error {{until C++1z}}
}
+
+namespace check_conversion_early {
+ struct X {};
+ template<int> struct A {};
+ template<X &x> struct A<x> {}; // expected-error {{not implicitly convertible}}
+
+ struct Y { constexpr operator int() const { return 0; } };
+ template<Y &y> struct A<y> {}; // expected-error {{depends on a template parameter of the partial specialization}}
+}
diff --git a/clang/test/SemaTemplate/temp_arg_nontype_cxx1z.cpp b/clang/test/SemaTemplate/temp_arg_nontype_cxx1z.cpp
index abfb0f2..97ecbdb 100644
--- a/clang/test/SemaTemplate/temp_arg_nontype_cxx1z.cpp
+++ b/clang/test/SemaTemplate/temp_arg_nontype_cxx1z.cpp
@@ -137,7 +137,7 @@
struct Z { constexpr operator Y&() { return y; } } z;
constexpr Y::operator Z&() { return z; }
template<Y &> struct D {};
- template<Z &z> int d(D<z>); // expected-note {{does not have the same type}}
+ template<Z &z> int d(D<z>); // expected-note {{couldn't infer template argument 'z'}}
int d_imp = d(D<y>()); // expected-error {{no matching function}}
int d_exp = d<y>(D<y>());
}