[Clang] Preserve more sugars in constraint evaluation (llvm#162991)

zyn0217 · web-flow · commit d72cd24ac438 · 2025-10-13T00:47:01.000+08:00
Using the canonical form of SugarConverted was an oversight during the iteration of e9972de. We now retain sugar for better diagnostics.
diff --git a/clang/lib/Sema/SemaConcept.cpp b/clang/lib/Sema/SemaConcept.cpp
@@ -614,8 +614,7 @@ ConstraintSatisfactionChecker::SubstitutionInTemplateArguments(
   for (unsigned I = 0, MappedIndex = 0; I < Used.size(); I++) {
     TemplateArgument Arg;
     if (Used[I])
-      Arg = S.Context.getCanonicalTemplateArgument(
-          CTAI.SugaredConverted[MappedIndex++]);
+      Arg = CTAI.SugaredConverted[MappedIndex++];
     if (I < SubstitutedOuterMost.size()) {
       SubstitutedOuterMost[I] = Arg;
       Offset = I + 1;
diff --git a/clang/test/CXX/expr/expr.prim/expr.prim.req/compound-requirement.cpp b/clang/test/CXX/expr/expr.prim/expr.prim.req/compound-requirement.cpp
@@ -149,7 +149,7 @@ namespace std_example {
   template<typename T> constexpr bool is_same_v<T, T> = true;
 
   template<typename T, typename U> concept same_as = is_same_v<T, U>;
-  // expected-note@-1 {{because 'is_same_v<int, typename std_example::T2::inner>' evaluated to false}}
+  // expected-note@-1 {{because 'is_same_v<int, typename T2::inner>' evaluated to false}}
 
   static_assert(C1<int>);
   static_assert(C1<int*>);
@@ -160,7 +160,7 @@ namespace std_example {
   template<typename T> concept C2 =
     requires(T x) {
       {*x} -> same_as<typename T::inner>;
-      // expected-note@-1{{because 'same_as<int, typename std_example::T2::inner>' evaluated to false}}
+      // expected-note@-1{{because 'same_as<int, typename T2::inner>' evaluated to false}}
       // expected-note@-2{{because '*x' would be invalid: indirection requires pointer operand ('int' invalid)}}
     };
 
diff --git a/clang/test/CXX/expr/expr.prim/expr.prim.req/nested-requirement.cpp b/clang/test/CXX/expr/expr.prim/expr.prim.req/nested-requirement.cpp
@@ -27,7 +27,7 @@ using r4i = X<void>::r4<int>; // expected-error{{constraints not satisfied for c
 
 // C++ [expr.prim.req.nested] Examples
 namespace std_example {
-  template<typename U> concept C1 = sizeof(U) == 1; // expected-note{{because 'sizeof(int) == 1' (4 == 1) evaluated to false}}
+  template<typename U> concept C1 = sizeof(U) == 1; // expected-note{{because 'sizeof(decltype(+t)) == 1' (4 == 1) evaluated to false}}
   template<typename T> concept D =
     requires (T t) {
       requires C1<decltype (+t)>; // expected-note{{because 'decltype(+t)' (aka 'int') does not satisfy 'C1'}}
diff --git a/clang/test/CXX/temp/temp.param/p10-2a.cpp b/clang/test/CXX/temp/temp.param/p10-2a.cpp
@@ -95,8 +95,8 @@ concept OneOf = (is_same_v<T, Ts> || ...); // #OneOf
 // expected-note@#OneOf 3{{because 'is_same_v<int, char[1]>' evaluated to false}}
 // expected-note@#OneOf 3{{and 'is_same_v<int, char[2]>' evaluated to false}}
 // expected-note@#OneOf {{because 'is_same_v<decltype(nullptr), char>' evaluated to false}}
-// expected-note@#OneOf {{because 'is_same_v<std::nullptr_t, char>' evaluated to false}}
-// expected-note@#OneOf {{and 'is_same_v<std::nullptr_t, int>' evaluated to false}}
+// expected-note@#OneOf {{because 'is_same_v<decltype(nullptr), char>' evaluated to false}}
+// expected-note@#OneOf {{and 'is_same_v<decltype(nullptr), int>' evaluated to false}}
 // expected-note@#OneOf {{and 'is_same_v<decltype(nullptr), int>' evaluated to false}}
 
 template<OneOf<char[1], char[2]> T, OneOf<int, long, char> U>
diff --git a/clang/test/SemaHLSL/BuiltIns/Buffers.hlsl b/clang/test/SemaHLSL/BuiltIns/Buffers.hlsl
@@ -20,7 +20,7 @@ Buffer<double2> r4;
 // expected-error@+4 {{constraints not satisfied for class template 'Buffer'}}
 // expected-note@*:* {{template declaration from hidden source: template <typename element_type> requires __is_typed_resource_element_compatible<element_type> class Buffer}}
 // expected-note@*:* {{because 'Buffer<int>' does not satisfy '__is_typed_resource_element_compatible'}}
-// expected-note@*:* {{because '__builtin_hlsl_is_typed_resource_element_compatible(hlsl::Buffer<int>)' evaluated to false}}
+// expected-note@*:* {{because '__builtin_hlsl_is_typed_resource_element_compatible(Buffer<int>)' evaluated to false}}
 Buffer<Buffer<int> > r5;
 
 struct s {
@@ -66,7 +66,7 @@ Buffer<half[4]> r10;
 typedef vector<int, 8> int8;
 // expected-error@+3 {{constraints not satisfied for class template 'Buffer'}}
 // expected-note@*:* {{because 'int8' (aka 'vector<int, 8>') does not satisfy '__is_typed_resource_element_compatible'}}
-// expected-note@*:* {{because '__builtin_hlsl_is_typed_resource_element_compatible(vector<int, 8>)' evaluated to false}}
+// expected-note@*:* {{because '__builtin_hlsl_is_typed_resource_element_compatible(int8)' evaluated to false}}
 Buffer<int8> r11;
 
 typedef int MyInt;
@@ -91,7 +91,7 @@ Buffer<numbers> r15;
 
 // expected-error@+3 {{constraints not satisfied for class template 'Buffer'}}
 // expected-note@*:* {{because 'double3' (aka 'vector<double, 3>') does not satisfy '__is_typed_resource_element_compatible'}}
-// expected-note@*:* {{because '__builtin_hlsl_is_typed_resource_element_compatible(vector<double, 3>)' evaluated to false}}
+// expected-note@*:* {{because '__builtin_hlsl_is_typed_resource_element_compatible(double3)' evaluated to false}}
 Buffer<double3> r16;
 
 
diff --git a/clang/test/SemaHLSL/BuiltIns/RWBuffers.hlsl b/clang/test/SemaHLSL/BuiltIns/RWBuffers.hlsl
@@ -20,7 +20,7 @@ RWBuffer<double2> r4;
 // expected-error@+4 {{constraints not satisfied for class template 'RWBuffer'}}
 // expected-note@*:* {{template declaration from hidden source: template <typename element_type> requires __is_typed_resource_element_compatible<element_type> class RWBuffer}}
 // expected-note@*:* {{because 'RWBuffer<int>' does not satisfy '__is_typed_resource_element_compatible'}}
-// expected-note@*:* {{because '__builtin_hlsl_is_typed_resource_element_compatible(hlsl::RWBuffer<int>)' evaluated to false}}
+// expected-note@*:* {{because '__builtin_hlsl_is_typed_resource_element_compatible(RWBuffer<int>)' evaluated to false}}
 RWBuffer<RWBuffer<int> > r5;
 
 struct s {
@@ -66,7 +66,7 @@ RWBuffer<half[4]> r10;
 typedef vector<int, 8> int8;
 // expected-error@+3 {{constraints not satisfied for class template 'RWBuffer'}}
 // expected-note@*:* {{because 'int8' (aka 'vector<int, 8>') does not satisfy '__is_typed_resource_element_compatible'}}
-// expected-note@*:* {{because '__builtin_hlsl_is_typed_resource_element_compatible(vector<int, 8>)' evaluated to false}}
+// expected-note@*:* {{because '__builtin_hlsl_is_typed_resource_element_compatible(int8)' evaluated to false}}
 RWBuffer<int8> r11;
 
 typedef int MyInt;
@@ -91,7 +91,7 @@ RWBuffer<numbers> r15;
 
 // expected-error@+3 {{constraints not satisfied for class template 'RWBuffer'}}
 // expected-note@*:* {{because 'double3' (aka 'vector<double, 3>') does not satisfy '__is_typed_resource_element_compatible'}}
-// expected-note@*:* {{because '__builtin_hlsl_is_typed_resource_element_compatible(vector<double, 3>)' evaluated to false}}
+// expected-note@*:* {{because '__builtin_hlsl_is_typed_resource_element_compatible(double3)' evaluated to false}}
 RWBuffer<double3> r16;
 
 
diff --git a/clang/test/SemaTemplate/concepts-recursive-inst.cpp b/clang/test/SemaTemplate/concepts-recursive-inst.cpp
@@ -68,8 +68,8 @@ struct my_range{
 void baz() {
 auto it = begin(rng); // #BEGIN_CALL
 // expected-error-re@#INF_REQ {{satisfaction of constraint {{.*}} depends on itself}}
-// expected-note@#INF_BEGIN {{while checking the satisfaction of concept 'Inf<DirectRecursiveCheck::my_range>' requested here}}
-// expected-note@#INF_BEGIN_EXPR {{while checking constraint satisfaction for template 'begin<DirectRecursiveCheck::my_range>' required here}}
+// expected-note@#INF_BEGIN {{while checking the satisfaction of concept 'Inf<struct my_range>' requested here}}
+// expected-note@#INF_BEGIN_EXPR {{while checking constraint satisfaction for template 'begin<struct my_range>' required here}}
 // expected-note@#INF_BEGIN_EXPR {{while substituting deduced template arguments into function template 'begin'}}
 // expected-note@#INF_BEGIN_EXPR {{in instantiation of requirement here}}
 // expected-note@#INF_REQ {{while substituting template arguments into constraint expression here}}
diff --git a/clang/test/SemaTemplate/concepts.cpp b/clang/test/SemaTemplate/concepts.cpp
@@ -833,13 +833,13 @@ struct Parent {
 static_assert(Parent<void>::TakesUnary<int, 0>::i == 0);
 // expected-error@+3{{constraints not satisfied for class template 'TakesUnary'}}
 // expected-note@#UNARY{{because 'decltype(0ULL)' (aka 'unsigned long long') does not satisfy 'C'}}
-// expected-note@#61777_C{{because 'sizeof(unsigned long long) == 4' (8 == 4) evaluated to false}}
+// expected-note@#61777_C{{because 'sizeof(decltype(0ULL)) == 4' (8 == 4) evaluated to false}}
 static_assert(Parent<void>::TakesUnary<int, 0uLL>::i == 0);
 
 static_assert(Parent<int>::TakesBinary<int, 0>::i == 0);
 // expected-error@+3{{constraints not satisfied for class template 'TakesBinary'}}
 // expected-note@#BINARY{{because 'C2<decltype(0ULL), int>' evaluated to false}}
-// expected-note@#61777_C2{{because 'sizeof(unsigned long long) == sizeof(int)' (8 == 4) evaluated to false}}
+// expected-note@#61777_C2{{because 'sizeof(decltype(0ULL)) == sizeof(int)' (8 == 4) evaluated to false}}
 static_assert(Parent<int>::TakesBinary<int, 0ULL>::i == 0);
 }
 
@@ -1329,8 +1329,8 @@ static_assert(__cpp17_iterator<not_move_constructible>); \
 // expected-error {{static assertion failed}} \
 // expected-note {{because 'not_move_constructible' does not satisfy '__cpp17_iterator'}} \
 // expected-note@#__cpp17_copy_constructible {{because 'not_move_constructible' does not satisfy '__cpp17_copy_constructible'}} \
-// expected-note@#__cpp17_move_constructible {{because 'parameter_mapping_regressions::case3::not_move_constructible' does not satisfy '__cpp17_move_constructible'}} \
-// expected-note@#is_move_constructible_v {{because 'is_move_constructible_v<parameter_mapping_regressions::case3::not_move_constructible>' evaluated to false}}
+// expected-note@#__cpp17_move_constructible {{because 'not_move_constructible' does not satisfy '__cpp17_move_constructible'}} \
+// expected-note@#is_move_constructible_v {{because 'is_move_constructible_v<not_move_constructible>' evaluated to false}}
 }
 
 namespace case4 {
