|  | // RUN: %clang_cc1 -triple x86_64-unknown-unknown -std=c++2a -ast-dump -ast-dump-filter Foo %s | FileCheck -strict-whitespace %s | 
|  |  | 
|  | // Test with serialization: | 
|  | // RUN: %clang_cc1 -std=c++20 -triple x86_64-unknown-unknown -emit-pch -o %t %s | 
|  | // RUN: %clang_cc1 -x c++ -std=c++20 -triple x86_64-unknown-unknown -include-pch %t \ | 
|  | // RUN: -ast-dump-all -ast-dump-filter Foo /dev/null \ | 
|  | // RUN: | FileCheck --strict-whitespace %s | 
|  |  | 
|  | template <typename T> | 
|  | concept unary_concept = true; | 
|  |  | 
|  | template <typename T, typename U> | 
|  | concept binary_concept = true; | 
|  |  | 
|  | template <typename... Ts> | 
|  | concept variadic_concept = true; | 
|  |  | 
|  | template <typename T> | 
|  | struct Foo { | 
|  | // CHECK:      TemplateTypeParmDecl {{.*}} referenced Concept {{.*}} 'binary_concept' | 
|  | // CHECK-NEXT: `-ConceptSpecializationExpr {{.*}} <col:13, col:31> 'bool' Concept {{.*}} 'binary_concept' | 
|  | // CHECK-NEXT:   |-ImplicitConceptSpecializationDecl {{.*}} <line:13:9> col:9 | 
|  | // CHECK-NEXT:   | |-TemplateArgument type 'type-parameter-1-0' | 
|  | // CHECK-NEXT:   | | `-TemplateTypeParmType {{.*}} 'type-parameter-1-0' dependent {{.*}}depth 1 index 0 | 
|  | // CHECK-NEXT:   | `-TemplateArgument type 'int' | 
|  | // CHECK-NEXT:   |   `-BuiltinType {{.*}} 'int' | 
|  | // CHECK-NEXT:   |-TemplateArgument {{.*}} type 'R' | 
|  | // CHECK-NEXT:   | `-TemplateTypeParmType {{.*}} 'R' | 
|  | // CHECK-NEXT:   |   `-TemplateTypeParm {{.*}} 'R' | 
|  | // CHECK-NEXT:   `-TemplateArgument {{.*}} type 'int' | 
|  | // CHECK-NEXT:     `-BuiltinType {{.*}} 'int' | 
|  | template <binary_concept<int> R> | 
|  | Foo(R); | 
|  |  | 
|  | // CHECK:      TemplateTypeParmDecl {{.*}} referenced Concept {{.*}} 'unary_concept' | 
|  | // CHECK-NEXT: `-ConceptSpecializationExpr {{.*}} <col:13> 'bool' | 
|  | // CHECK-NEXT:   |-ImplicitConceptSpecializationDecl {{.*}} <line:10:9> col:9 | 
|  | // CHECK-NEXT:   | `-TemplateArgument type 'type-parameter-1-0' | 
|  | // CHECK-NEXT:   |   `-TemplateTypeParmType {{.*}} 'type-parameter-1-0' dependent {{.*}}depth 1 index 0 | 
|  | template <unary_concept R> | 
|  | Foo(R); | 
|  |  | 
|  | // CHECK:      FunctionTemplateDecl {{.*}} <line:[[@LINE+1]]:3, line:[[@LINE+2]]:39> {{.*}} Foo<T> | 
|  | template <typename R> | 
|  | Foo(R, int) requires unary_concept<R>; | 
|  |  | 
|  | // CHECK:      FunctionTemplateDecl {{.*}} <line:[[@LINE+1]]:3, line:[[@LINE+3]]:3> {{.*}} Foo<T> | 
|  | template <typename R> | 
|  | Foo(R, char) requires unary_concept<R> { | 
|  | } | 
|  |  | 
|  | // CHECK: CXXFoldExpr {{.*}} <col:13, col:29> | 
|  | template <variadic_concept... Ts> | 
|  | Foo(); | 
|  |  | 
|  | // CHECK: CXXFoldExpr {{.*}} <col:13, col:34> | 
|  | template <variadic_concept<int>... Ts> | 
|  | Foo(); | 
|  | }; |