[clang] 60a085b - Revert "[clang] deprecate frelaxed-template-template-args, make it on by default"
Yaxun Liu via cfe-commits
cfe-commits at lists.llvm.org
Tue Nov 2 14:03:30 PDT 2021
Author: Yaxun (Sam) Liu
Date: 2021-11-02T17:02:19-04:00
New Revision: 60a085beb04b055cf44c379c56cb247cb3587658
URL: https://github.com/llvm/llvm-project/commit/60a085beb04b055cf44c379c56cb247cb3587658
DIFF: https://github.com/llvm/llvm-project/commit/60a085beb04b055cf44c379c56cb247cb3587658.diff
LOG: Revert "[clang] deprecate frelaxed-template-template-args, make it on by default"
This reverts commit 2d7fba5f95f0614f6f2c4a4ed966b307d617898b.
The patch was reverted because it caused regression with rocThrust
due to ambiguity of template specialization.
For details please see https://reviews.llvm.org/D109496
Added:
Modified:
clang/include/clang/Basic/DiagnosticDriverKinds.td
clang/include/clang/Basic/LangOptions.def
clang/include/clang/Driver/Options.td
clang/lib/Driver/SanitizerArgs.cpp
clang/lib/Driver/ToolChains/Clang.cpp
clang/lib/Driver/ToolChains/CommonArgs.cpp
clang/lib/Sema/SemaTemplate.cpp
clang/test/CXX/temp/temp.arg/temp.arg.template/p3-2a.cpp
clang/test/Lexer/cxx-features.cpp
clang/test/SemaTemplate/deduction.cpp
clang/test/SemaTemplate/default-arguments.cpp
clang/test/SemaTemplate/instantiate-template-template-parm.cpp
clang/test/SemaTemplate/nested-template.cpp
clang/test/SemaTemplate/temp_arg_template.cpp
clang/test/SemaTemplate/temp_arg_template_cxx1z.cpp
clang/www/cxx_status.html
Removed:
clang/test/Driver/frelaxed-template-template-args.cpp
################################################################################
diff --git a/clang/include/clang/Basic/DiagnosticDriverKinds.td b/clang/include/clang/Basic/DiagnosticDriverKinds.td
index b823ade0eafb5..fa464952189ba 100644
--- a/clang/include/clang/Basic/DiagnosticDriverKinds.td
+++ b/clang/include/clang/Basic/DiagnosticDriverKinds.td
@@ -355,7 +355,7 @@ def warn_drv_diagnostics_hotness_requires_pgo : Warning<
def warn_drv_clang_unsupported : Warning<
"the clang compiler does not support '%0'">;
def warn_drv_deprecated_arg : Warning<
- "argument '%0' is deprecated%select{|, use '%2' instead}1">, InGroup<Deprecated>;
+ "argument '%0' is deprecated, use '%1' instead">, InGroup<Deprecated>;
def warn_drv_assuming_mfloat_abi_is : Warning<
"unknown platform, assuming -mfloat-abi=%0">;
def warn_ignoring_ftabstop_value : Warning<
diff --git a/clang/include/clang/Basic/LangOptions.def b/clang/include/clang/Basic/LangOptions.def
index 565ecd94f977c..4651f4fff6aa0 100644
--- a/clang/include/clang/Basic/LangOptions.def
+++ b/clang/include/clang/Basic/LangOptions.def
@@ -149,7 +149,7 @@ LANGOPT(NoMathBuiltin , 1, 0, "disable math builtin functions")
LANGOPT(GNUAsm , 1, 1, "GNU-style inline assembly")
LANGOPT(Coroutines , 1, 0, "C++20 coroutines")
LANGOPT(DllExportInlines , 1, 1, "dllexported classes dllexport inline methods")
-LANGOPT(RelaxedTemplateTemplateArgs, 1, 1, "C++17 relaxed matching of template template arguments")
+LANGOPT(RelaxedTemplateTemplateArgs, 1, 0, "C++17 relaxed matching of template template arguments")
LANGOPT(DoubleSquareBracketAttributes, 1, 0, "'[[]]' attributes extension for all language standard modes")
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index 0d3c053e89ae4..b4a2411fa5c5c 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -2335,9 +2335,9 @@ defm application_extension : BoolFOption<"application-extension",
PosFlag<SetTrue, [CC1Option], "Restrict code to those available for App Extensions">,
NegFlag<SetFalse>>;
defm relaxed_template_template_args : BoolFOption<"relaxed-template-template-args",
- LangOpts<"RelaxedTemplateTemplateArgs">, DefaultTrue,
- PosFlag<SetTrue>,
- NegFlag<SetFalse, [CC1Option], "Disable C++17 relaxed template template argument matching">>;
+ LangOpts<"RelaxedTemplateTemplateArgs">, DefaultFalse,
+ PosFlag<SetTrue, [CC1Option], "Enable C++17 relaxed template template argument matching">,
+ NegFlag<SetFalse>>;
defm sized_deallocation : BoolFOption<"sized-deallocation",
LangOpts<"SizedDeallocation">, DefaultFalse,
PosFlag<SetTrue, [CC1Option], "Enable C++14 sized global deallocation functions">,
diff --git a/clang/lib/Driver/SanitizerArgs.cpp b/clang/lib/Driver/SanitizerArgs.cpp
index 6f426c6cad69c..36579060d8a26 100644
--- a/clang/lib/Driver/SanitizerArgs.cpp
+++ b/clang/lib/Driver/SanitizerArgs.cpp
@@ -683,8 +683,7 @@ SanitizerArgs::SanitizerArgs(const ToolChain &TC,
Arg->claim();
if (LegacySanitizeCoverage != 0) {
D.Diag(diag::warn_drv_deprecated_arg)
- << Arg->getAsString(Args) << true
- << "-fsanitize-coverage=trace-pc-guard";
+ << Arg->getAsString(Args) << "-fsanitize-coverage=trace-pc-guard";
}
continue;
}
@@ -719,11 +718,11 @@ SanitizerArgs::SanitizerArgs(const ToolChain &TC,
// enabled.
if (CoverageFeatures & CoverageTraceBB)
D.Diag(clang::diag::warn_drv_deprecated_arg)
- << "-fsanitize-coverage=trace-bb" << true
+ << "-fsanitize-coverage=trace-bb"
<< "-fsanitize-coverage=trace-pc-guard";
if (CoverageFeatures & Coverage8bitCounters)
D.Diag(clang::diag::warn_drv_deprecated_arg)
- << "-fsanitize-coverage=8bit-counters" << true
+ << "-fsanitize-coverage=8bit-counters"
<< "-fsanitize-coverage=trace-pc-guard";
int InsertionPointTypes = CoverageFunc | CoverageBB | CoverageEdge;
@@ -733,7 +732,7 @@ SanitizerArgs::SanitizerArgs(const ToolChain &TC,
if ((CoverageFeatures & InsertionPointTypes) &&
!(CoverageFeatures & InstrumentationTypes)) {
D.Diag(clang::diag::warn_drv_deprecated_arg)
- << "-fsanitize-coverage=[func|bb|edge]" << true
+ << "-fsanitize-coverage=[func|bb|edge]"
<< "-fsanitize-coverage=[func|bb|edge],[trace-pc-guard|trace-pc]";
}
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index 9856a42e1db53..c77413ddf1ace 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -6391,14 +6391,12 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
options::OPT_fno_assume_sane_operator_new))
CmdArgs.push_back("-fno-assume-sane-operator-new");
- // -frelaxed-template-template-args is deprecated and on by default.
- if (Arg *A =
- Args.getLastArg(options::OPT_frelaxed_template_template_args,
- options::OPT_fno_relaxed_template_template_args)) {
- D.Diag(diag::warn_drv_deprecated_arg) << A->getAsString(Args) << false;
- if (A->getOption().matches(options::OPT_fno_relaxed_template_template_args))
- CmdArgs.push_back("-fno-relaxed-template-template-args");
- }
+ // -frelaxed-template-template-args is off by default, as it is a severe
+ // breaking change until a corresponding change to template partial ordering
+ // is provided.
+ if (Args.hasFlag(options::OPT_frelaxed_template_template_args,
+ options::OPT_fno_relaxed_template_template_args, false))
+ CmdArgs.push_back("-frelaxed-template-template-args");
// -fsized-deallocation is off by default, as it is an ABI-breaking change for
// most platforms.
diff --git a/clang/lib/Driver/ToolChains/CommonArgs.cpp b/clang/lib/Driver/ToolChains/CommonArgs.cpp
index b796bd341e12b..c3abdf446cfaf 100644
--- a/clang/lib/Driver/ToolChains/CommonArgs.cpp
+++ b/clang/lib/Driver/ToolChains/CommonArgs.cpp
@@ -1890,12 +1890,12 @@ void tools::checkAMDGPUCodeObjectVersion(const Driver &D,
// Emit warnings for legacy options even if they are overridden.
if (Args.hasArg(options::OPT_mno_code_object_v3_legacy))
- D.Diag(diag::warn_drv_deprecated_arg)
- << "-mno-code-object-v3" << true << "-mcode-object-version=2";
+ D.Diag(diag::warn_drv_deprecated_arg) << "-mno-code-object-v3"
+ << "-mcode-object-version=2";
if (Args.hasArg(options::OPT_mcode_object_v3_legacy))
- D.Diag(diag::warn_drv_deprecated_arg)
- << "-mcode-object-v3" << true << "-mcode-object-version=3";
+ D.Diag(diag::warn_drv_deprecated_arg) << "-mcode-object-v3"
+ << "-mcode-object-version=3";
if (auto *CodeObjArg = getAMDGPUCodeObjectArgument(D, Args)) {
if (CodeObjArg->getOption().getID() ==
diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index aed96e1f404fc..6ff87eb61bf79 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -7407,7 +7407,9 @@ bool Sema::CheckTemplateTemplateArgument(TemplateTemplateParmDecl *Param,
// C++1z [temp.arg.template]p3: (DR 150)
// A template-argument matches a template template-parameter P when P
// is at least as specialized as the template-argument A.
- // FIXME: RelaxedTemplateTemplateArgs is deprecated, should be always on.
+ // FIXME: We should enable RelaxedTemplateTemplateArgs by default as it is a
+ // defect report resolution from C++17 and shouldn't be introduced by
+ // concepts.
if (getLangOpts().RelaxedTemplateTemplateArgs) {
// Quick check for the common case:
// If P contains a parameter pack, then A [...] matches P if each of A's
diff --git a/clang/test/CXX/temp/temp.arg/temp.arg.template/p3-2a.cpp b/clang/test/CXX/temp/temp.arg/temp.arg.template/p3-2a.cpp
index 2acdc2ca96b8e..8e69f134a3d14 100644
--- a/clang/test/CXX/temp/temp.arg/temp.arg.template/p3-2a.cpp
+++ b/clang/test/CXX/temp/temp.arg/temp.arg.template/p3-2a.cpp
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -std=c++2a -verify %s
+// RUN: %clang_cc1 -std=c++2a -frelaxed-template-template-args -verify %s
template<typename T> concept C = T::f();
// expected-note at -1{{similar constraint}}
diff --git a/clang/test/Driver/frelaxed-template-template-args.cpp b/clang/test/Driver/frelaxed-template-template-args.cpp
deleted file mode 100644
index dd6265ba8375e..0000000000000
--- a/clang/test/Driver/frelaxed-template-template-args.cpp
+++ /dev/null
@@ -1,5 +0,0 @@
-// RUN: %clang -fsyntax-only -frelaxed-template-template-args %s 2>&1 | FileCheck --check-prefix=CHECK-ON %s
-// RUN: %clang -fsyntax-only -fno-relaxed-template-template-args %s 2>&1 | FileCheck --check-prefix=CHECK-OFF %s
-
-// CHECK-ON: warning: argument '-frelaxed-template-template-args' is deprecated [-Wdeprecated]
-// CHECK-OFF: warning: argument '-fno-relaxed-template-template-args' is deprecated [-Wdeprecated]
diff --git a/clang/test/Lexer/cxx-features.cpp b/clang/test/Lexer/cxx-features.cpp
index a36986c2551b2..40c73f6019420 100644
--- a/clang/test/Lexer/cxx-features.cpp
+++ b/clang/test/Lexer/cxx-features.cpp
@@ -5,7 +5,7 @@
// RUN: %clang_cc1 -std=c++20 -fcxx-exceptions -fsized-deallocation -verify %s
// RUN: %clang_cc1 -std=c++2b -fcxx-exceptions -fsized-deallocation -verify %s
//
-// RUN: %clang_cc1 -std=c++17 -fcxx-exceptions -fsized-deallocation -fno-relaxed-template-template-args -DNO_RELAXED_TEMPLATE_TEMPLATE_ARGS=1 -verify %s
+// RUN: %clang_cc1 -std=c++17 -fcxx-exceptions -fsized-deallocation -frelaxed-template-template-args -DRELAXED_TEMPLATE_TEMPLATE_ARGS=1 -verify %s
// RUN: %clang_cc1 -std=c++17 -fcxx-exceptions -fsized-deallocation -DCONCEPTS_TS=1 -verify %s
// RUN: %clang_cc1 -std=c++14 -fno-rtti -fno-threadsafe-statics -verify %s -DNO_EXCEPTIONS -DNO_RTTI -DNO_THREADSAFE_STATICS -fsized-deallocation
// RUN: %clang_cc1 -std=c++14 -fcoroutines-ts -DNO_EXCEPTIONS -DCOROUTINES -verify -fsized-deallocation %s
@@ -195,9 +195,9 @@
#error "wrong value for __cpp_nontype_template_args"
#endif
-#if defined(NO_RELAXED_TEMPLATE_TEMPLATE_ARGS) \
- ? check(template_template_args, 0, 0, 0, 0, 0, 0) \
- : check(template_template_args, 201611, 201611, 201611, 201611, 201611, 201611)
+#if defined(RELAXED_TEMPLATE_TEMPLATE_ARGS) \
+ ? check(template_template_args, 0, 0, 0, 201611, 201611, 201611) \
+ : check(template_template_args, 0, 0, 0, 0, 0, 0)
#error "wrong value for __cpp_template_template_args"
#endif
diff --git a/clang/test/SemaTemplate/deduction.cpp b/clang/test/SemaTemplate/deduction.cpp
index 964f8b4896e7a..9c75595bc74a5 100644
--- a/clang/test/SemaTemplate/deduction.cpp
+++ b/clang/test/SemaTemplate/deduction.cpp
@@ -60,14 +60,12 @@ struct Replace<const T, Arg1, Arg2> {
// Replacement of templates
template<template<typename> class TT, typename T1, typename Arg1, typename Arg2>
struct Replace<TT<T1>, Arg1, Arg2> {
-// expected-note at -1 2 {{partial specialization matches}}
typedef TT<typename Replace<T1, Arg1, Arg2>::type> type;
};
template<template<typename, typename> class TT, typename T1, typename T2,
typename Arg1, typename Arg2>
struct Replace<TT<T1, T2>, Arg1, Arg2> {
-// expected-note at -1 2 {{partial specialization matches}}
typedef TT<typename Replace<T1, Arg1, Arg2>::type,
typename Replace<T2, Arg1, Arg2>::type> type;
};
@@ -81,19 +79,8 @@ struct Replace<TT<T1, _2>, Arg1, Arg2> {
int array0[is_same<Replace<_1, int, float>::type, int>::value? 1 : -1];
int array1[is_same<Replace<const _1, int, float>::type, const int>::value? 1 : -1];
-
int array2[is_same<Replace<vector<_1>, int, float>::type, vector<int> >::value? 1 : -1];
-// expected-error at -1 {{ambiguous partial specializations of 'Replace<vector<_1>, int, float>'}}
-// FIXME: Some bad error recovery from the parser here:
-// expected-error at -3 {{expected '(' for function-style cast or type construction}}
-// expected-error at -4 {{no member named 'value' in the global namespace}}
-
int array3[is_same<Replace<vector<const _1>, int, float>::type, vector<const int> >::value? 1 : -1];
-// expected-error at -1 {{ambiguous partial specializations of 'Replace<vector<const _1>, int, float>'}}
-// FIXME: Some bad error recovery from the parser here:
-// expected-error at -3 {{expected '(' for function-style cast or type construction}}
-// expected-error at -4 {{no member named 'value' in the global namespace}}
-
int array4[is_same<Replace<vector<int, _2>, double, float>::type, vector<int, float> >::value? 1 : -1];
// PR5911
diff --git a/clang/test/SemaTemplate/default-arguments.cpp b/clang/test/SemaTemplate/default-arguments.cpp
index 84178b7e26d14..882b279de1d08 100644
--- a/clang/test/SemaTemplate/default-arguments.cpp
+++ b/clang/test/SemaTemplate/default-arguments.cpp
@@ -112,14 +112,15 @@ template<typename T, template<typename> class X = T::template apply>
int array4[is_same<X4<add_pointer>,
X4<add_pointer, add_pointer::apply> >::value? 1 : -1];
-template<int> struct X5 {};
+template<int> struct X5 {}; // expected-note{{has a
diff erent type 'int'}}
template<long> struct X5b {};
template<typename T,
- template<T> class B = X5>
+ template<T> class B = X5> // expected-error{{template template argument has
diff erent}} \
+ // expected-note{{previous non-type template parameter}}
struct X6 {};
X6<int> x6a;
-X6<long> x6b;
+X6<long> x6b; // expected-note{{while checking a default template argument}}
X6<long, X5b> x6c;
diff --git a/clang/test/SemaTemplate/instantiate-template-template-parm.cpp b/clang/test/SemaTemplate/instantiate-template-template-parm.cpp
index f97e5b7c548e8..a70c7e8b081a4 100644
--- a/clang/test/SemaTemplate/instantiate-template-template-parm.cpp
+++ b/clang/test/SemaTemplate/instantiate-template-template-parm.cpp
@@ -20,29 +20,30 @@ apply<add_reference, int>::type ir = i;
apply<add_reference, float>::type fr = i; // expected-error{{non-const lvalue reference to type 'float' cannot bind to a value of unrelated type 'int'}}
// Template template parameters
-template<int> struct B;
+template<int> struct B; // expected-note{{has a
diff erent type 'int'}}
template<typename T,
- template<T Value> class X> // expected-error{{cannot have type 'float'}}
+ template<T Value> class X> // expected-error{{cannot have type 'float'}} \
+ // expected-note{{with type 'long'}}
struct X0 { };
X0<int, B> x0b1;
X0<float, B> x0b2; // expected-note{{while substituting}}
-X0<long, B> x0b3;
+X0<long, B> x0b3; // expected-error{{template template argument has
diff erent template parameters}}
-template<template<int V> class TT>
+template<template<int V> class TT> // expected-note{{parameter with type 'int'}}
struct X1 { };
template<typename T, template<T V> class TT>
struct X2 {
- X1<TT> x1;
+ X1<TT> x1; // expected-error{{has
diff erent template parameters}}
};
template<int V> struct X3i { };
-template<long V> struct X3l { };
+template<long V> struct X3l { }; // expected-note{{
diff erent type 'long'}}
X2<int, X3i> x2okay;
-X2<long, X3l> x2bad;
+X2<long, X3l> x2bad; // expected-note{{instantiation}}
template <typename T, template <T, T> class TT, class R = TT<1, 2> >
struct Comp {
diff --git a/clang/test/SemaTemplate/nested-template.cpp b/clang/test/SemaTemplate/nested-template.cpp
index 5bd388d4dff3d..efbde2076b9fa 100644
--- a/clang/test/SemaTemplate/nested-template.cpp
+++ b/clang/test/SemaTemplate/nested-template.cpp
@@ -112,16 +112,18 @@ template struct X1<int>::B<bool>;
// Template template parameters
template<typename T>
struct X2 {
- template<template<class U, T Value> class> // expected-error{{cannot have type 'float'}}
+ template<template<class U, T Value> class> // expected-error{{cannot have type 'float'}} \
+ // expected-note{{previous non-type template}}
struct Inner { };
};
-template<typename T, int Value>
+template<typename T,
+ int Value> // expected-note{{template non-type parameter}}
struct X2_arg;
X2<int>::Inner<X2_arg> x2i1;
X2<float> x2a; // expected-note{{instantiation}}
-X2<long>::Inner<X2_arg> x2i3;
+X2<long>::Inner<X2_arg> x2i3; // expected-error{{template template argument has
diff erent}}
namespace PR10896 {
template<typename TN>
diff --git a/clang/test/SemaTemplate/temp_arg_template.cpp b/clang/test/SemaTemplate/temp_arg_template.cpp
index 42926fa368929..37e1e52521263 100644
--- a/clang/test/SemaTemplate/temp_arg_template.cpp
+++ b/clang/test/SemaTemplate/temp_arg_template.cpp
@@ -6,11 +6,11 @@ template<template<typename T> class X> struct A; // expected-note 2{{previous te
template<template<typename T, int I> class X> struct B; // expected-note{{previous template template parameter is here}}
-template<template<int I> class X> struct C; // expected-note {{previous non-type template parameter with type 'int' is here}}
+template<template<int I> class X> struct C; // expected-note 2{{previous non-type template parameter with type 'int' is here}}
template<class> struct X; // expected-note{{too few template parameters in template template argument}}
template<int N> struct Y; // expected-note{{template parameter has a
diff erent kind in template argument}}
-template<long N> struct Ylong;
+template<long N> struct Ylong; // expected-note{{template non-type parameter has a
diff erent type 'long' in template argument}}
template<const int &N> struct Yref; // expected-note{{template non-type parameter has a
diff erent type 'const int &' in template argument}}
namespace N {
@@ -27,7 +27,7 @@ A<Y> *a4; // expected-error{{template template argument has
diff erent template p
A<TooMany> *a5; // expected-error{{template template argument has
diff erent template parameters than its corresponding template template parameter}}
B<X> *a6; // expected-error{{template template argument has
diff erent template parameters than its corresponding template template parameter}}
C<Y> *a7;
-C<Ylong> *a8;
+C<Ylong> *a8; // expected-error{{template template argument has
diff erent template parameters than its corresponding template template parameter}}
C<Yref> *a9; // expected-error{{template template argument has
diff erent template parameters than its corresponding template template parameter}}
template<typename T> void f(int);
diff --git a/clang/test/SemaTemplate/temp_arg_template_cxx1z.cpp b/clang/test/SemaTemplate/temp_arg_template_cxx1z.cpp
index 372a00efc601e..03ef78f8cf14e 100644
--- a/clang/test/SemaTemplate/temp_arg_template_cxx1z.cpp
+++ b/clang/test/SemaTemplate/temp_arg_template_cxx1z.cpp
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -fsyntax-only -verify -std=c++1z %s
+// RUN: %clang_cc1 -fsyntax-only -verify -std=c++1z -frelaxed-template-template-args %s
// expected-note at temp_arg_template_cxx1z.cpp:* 1+{{}}
diff --git a/clang/www/cxx_status.html b/clang/www/cxx_status.html
index db30a79a634ad..6894ca1b1ea64 100755
--- a/clang/www/cxx_status.html
+++ b/clang/www/cxx_status.html
@@ -596,7 +596,7 @@ <h2 id="cxx17">C++17 implementation status</h2>
<p>You can use Clang in C++17 mode with the <code>-std=c++17</code> option
(use <code>-std=c++1z</code> in Clang 4 and earlier).</p>
-<details>
+<details open>
<summary>List of features and minimum Clang version with support</summary>
<table width="689" border="1" cellspacing="0">
@@ -813,8 +813,8 @@ <h2 id="cxx17">C++17 implementation status</h2>
<!-- Issaquah 2016 papers -->
<tr>
<td>Matching template template parameters to compatible arguments</td>
- <td><a href="https://wg21.link/p0522r0">P0522R0</a> (<a href="#dr">DR</a>)</td>
- <td class="full" align="center">Clang 4 <a href="#p0522">(10)</a></td>
+ <td><a href="https://wg21.link/p0522r0">P0522R0</a></td>
+ <td class="partial" align="center">Partial <a href="#p0522">(10)</a></td>
</tr>
<tr>
<td>Removing deprecated dynamic exception specifications</td>
@@ -842,10 +842,13 @@ <h2 id="cxx17">C++17 implementation status</h2>
reverse construction order in that ABI.
This is not fully supported during constant expression evaluation until Clang 12.
</span><br>
-<span id="p0522">(10): Prior to Clang 14, this feature is not enabled by
-default, but can be enabled with <tt>-frelaxed-template-template-args</tt>.
-Starting from Clang 14, the flag is deprecated and will be removed in a future
-version.
+<span id="p0522">(10): Despite being the resolution to a Defect Report, this
+feature is disabled by default in all language versions, and can be enabled
+explicitly with the flag <tt>-frelaxed-template-template-args</tt> in Clang 4
+onwards.
+The change to the standard lacks a corresponding change for template partial
+ordering, resulting in ambiguity errors for reasonable and previously-valid
+code. This issue is expected to be rectified soon.
</span>
</p>
</details>
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