diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -1526,12 +1526,12 @@
 
 // C++ declarations
 def err_static_assert_expression_is_not_constant : Error<
-  "static_assert expression is not an integral constant expression">;
+  "static assertion expression is not an integral constant expression">;
 def err_constexpr_if_condition_expression_is_not_constant : Error<
   "constexpr if condition is not a constant expression">;
-def err_static_assert_failed : Error<"static_assert failed%select{: %1|}0">;
+def err_static_assert_failed : Error<"static assertion failed%select{: %1|}0">;
 def err_static_assert_requirement_failed : Error<
-  "static_assert failed due to requirement '%0'%select{: %2|}1">;
+  "static assertion failed due to requirement '%0'%select{: %2|}1">;
 
 def warn_consteval_if_always_true : Warning<
   "consteval if is always true in an %select{unevaluated|immediate}0 context">,
diff --git a/clang/test/C/drs/dr0xx.c b/clang/test/C/drs/dr0xx.c
--- a/clang/test/C/drs/dr0xx.c
+++ b/clang/test/C/drs/dr0xx.c
@@ -203,7 +203,7 @@
  * Note: the rule changed in C99 to be different than the resolution to DR029,
  * so it's not clear there's value in implementing this DR.
  */
-_Static_assert(__builtin_types_compatible_p(struct S { int a; }, union U { int a; }), "fail"); /* expected-error {{static_assert failed due to requirement '__builtin_types_compatible_p(struct S, union U)': fail}} */
+_Static_assert(__builtin_types_compatible_p(struct S { int a; }, union U { int a; }), "fail"); /* expected-error {{static assertion failed due to requirement '__builtin_types_compatible_p(struct S, union U)': fail}} */
 
 /* WG14 DR031: yes
  * Can constant expressions overflow?
diff --git a/clang/test/CXX/dcl.dcl/p4-0x.cpp b/clang/test/CXX/dcl.dcl/p4-0x.cpp
--- a/clang/test/CXX/dcl.dcl/p4-0x.cpp
+++ b/clang/test/CXX/dcl.dcl/p4-0x.cpp
@@ -18,4 +18,4 @@
 static_assert(T(), "");
 static_assert(U(), ""); // expected-error {{ambiguous}}
 
-static_assert(false, L"\x14hi" "!" R"x(")x"); // expected-error {{static_assert failed: L"\024hi!\""}}
+static_assert(false, L"\x14hi" "!" R"x(")x"); // expected-error {{static assertion failed: L"\024hi!\""}}
diff --git a/clang/test/CXX/drs/dr19xx.cpp b/clang/test/CXX/drs/dr19xx.cpp
--- a/clang/test/CXX/drs/dr19xx.cpp
+++ b/clang/test/CXX/drs/dr19xx.cpp
@@ -83,7 +83,7 @@
 #if __cplusplus >= 201103L
 static union {
   static_assert(true, "");  // ok
-  static_assert(false, ""); // expected-error {{static_assert failed}}
+  static_assert(false, ""); // expected-error {{static assertion failed}}
   int not_empty;
 };
 #endif
diff --git a/clang/test/CXX/expr/expr.prim/expr.prim.id/p3.cpp b/clang/test/CXX/expr/expr.prim/expr.prim.id/p3.cpp
--- a/clang/test/CXX/expr/expr.prim/expr.prim.id/p3.cpp
+++ b/clang/test/CXX/expr/expr.prim/expr.prim.id/p3.cpp
@@ -161,10 +161,10 @@
 
 struct small { };
 static_assert(Large<small>);
-// expected-error@-1 {{static_assert failed}}
+// expected-error@-1 {{static assertion failed}}
 // expected-note@-2 {{because 'small' does not satisfy 'Large'}}
 static_assert(Large<small>, "small isn't large");
-// expected-error@-1 {{static_assert failed: small isn't large}}
+// expected-error@-1 {{static assertion failed: small isn't large}}
 // expected-note@-2 {{because 'small' does not satisfy 'Large'}}
 
 // Make sure access-checking can fail a concept specialization
@@ -173,7 +173,7 @@
 template<typename T> concept AccessPrivate = T{}.f;
 // expected-note@-1{{because substituted constraint expression is ill-formed: 'f' is a private member of 'T4'}}
 static_assert(AccessPrivate<T4>);
-// expected-error@-1{{static_assert failed}}
+// expected-error@-1{{static assertion failed}}
 // expected-note@-2{{because 'T4' does not satisfy 'AccessPrivate'}}
 
 template<typename T, typename U>
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
--- 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
@@ -43,5 +43,5 @@
       requires sizeof(a) == 4; // OK
       requires a == 0; // expected-note{{because 'a == 0' would be invalid: constraint variable 'a' cannot be used in an evaluated context}}
     };
-  static_assert(C2<int>); // expected-note{{because 'int' does not satisfy 'C2'}} expected-error{{static_assert failed}}
-}
\ No newline at end of file
+  static_assert(C2<int>); // expected-note{{because 'int' does not satisfy 'C2'}} expected-error{{static assertion failed}}
+}
diff --git a/clang/test/CXX/temp/temp.constr/temp.constr.constr/partial-specializations.cpp b/clang/test/CXX/temp/temp.constr/temp.constr.constr/partial-specializations.cpp
--- a/clang/test/CXX/temp/temp.constr/temp.constr.constr/partial-specializations.cpp
+++ b/clang/test/CXX/temp/temp.constr/temp.constr.constr/partial-specializations.cpp
@@ -79,6 +79,6 @@
   // expected-note@-1{{while checking constraint satisfaction for variable template partial specialization 'v1<int>' required here}}
   // expected-note@-2{{during template argument deduction for variable template partial specialization 'v1<T *>' [with T = int *]}}
   // expected-note@-3{{during template argument deduction for variable template partial specialization 'v1<T **>' [with T = int]}}
-  // expected-error@-4{{static_assert failed due to requirement 'v1<int **>'}}
+  // expected-error@-4{{static assertion failed due to requirement 'v1<int **>'}}
 
-}
\ No newline at end of file
+}
diff --git a/clang/test/PCH/cxx-static_assert.cpp b/clang/test/PCH/cxx-static_assert.cpp
--- a/clang/test/PCH/cxx-static_assert.cpp
+++ b/clang/test/PCH/cxx-static_assert.cpp
@@ -17,7 +17,7 @@
 
 #else
 
-// expected-error@15 {{static_assert failed due to requirement '1 == 2': N is not 2!}}
+// expected-error@15 {{static assertion failed due to requirement '1 == 2': N is not 2!}}
 T<1> t1; // expected-note {{in instantiation of template class 'T<1>' requested here}}
 T<2> t2;
 
diff --git a/clang/test/PCH/cxx-templates.cpp b/clang/test/PCH/cxx-templates.cpp
--- a/clang/test/PCH/cxx-templates.cpp
+++ b/clang/test/PCH/cxx-templates.cpp
@@ -167,7 +167,7 @@
   // This used to mark 'f' invalid without producing any diagnostic. That's a
   // little hard to detect, but we can make sure that constexpr evaluation
   // fails when it should.
-  static_assert(A<int>().f() == 1); // expected-error {{static_assert failed}}
+  static_assert(A<int>().f() == 1); // expected-error {{static assertion failed}}
 #endif
 }
 
diff --git a/clang/test/Parser/objc-static-assert.m b/clang/test/Parser/objc-static-assert.m
--- a/clang/test/Parser/objc-static-assert.m
+++ b/clang/test/Parser/objc-static-assert.m
@@ -15,7 +15,7 @@
 @interface A {
   int a;
   _Static_assert(1, "");
-  _Static_assert(0, ""); // expected-error {{static_assert failed}}
+  _Static_assert(0, ""); // expected-error {{static assertion failed}}
 
   _Static_assert(a, ""); // expected-error {{use of undeclared identifier 'a'}}
   _Static_assert(sizeof(a), ""); // expected-error {{use of undeclared identifier 'a'}}
@@ -44,7 +44,7 @@
 @interface A {
   int a;
   _Static_assert(1, "");
-  _Static_assert(0, ""); // expected-error {{static_assert failed}}
+  _Static_assert(0, ""); // expected-error {{static assertion failed}}
 }
 
 _Static_assert(1, "");
diff --git a/clang/test/Parser/objc-static-assert.mm b/clang/test/Parser/objc-static-assert.mm
--- a/clang/test/Parser/objc-static-assert.mm
+++ b/clang/test/Parser/objc-static-assert.mm
@@ -21,12 +21,12 @@
   static_assert(1, "");
   _Static_assert(1, "");
 
-  static_assert(0, ""); // expected-error {{static_assert failed}}
-  _Static_assert(0, ""); // expected-error {{static_assert failed}}
+  static_assert(0, ""); // expected-error {{static assertion failed}}
+  _Static_assert(0, ""); // expected-error {{static assertion failed}}
 
-  static_assert(a, ""); // expected-error {{static_assert expression is not an integral constant expression}}
+  static_assert(a, ""); // expected-error {{static assertion expression is not an integral constant expression}}
   static_assert(sizeof(a) == 4, "");
-  static_assert(sizeof(a) == 3, ""); // expected-error {{static_assert failed}}
+  static_assert(sizeof(a) == 3, ""); // expected-error {{static assertion failed}}
 }
 
 static_assert(1, "");
@@ -40,7 +40,7 @@
   static_assert(1, "");
   _Static_assert(1, "");
   static_assert(sizeof(b) == 4, "");
-  static_assert(sizeof(b) == 3, ""); // expected-error {{static_assert failed}}
+  static_assert(sizeof(b) == 3, ""); // expected-error {{static assertion failed}}
 }
 
 static_assert(1, "");
@@ -56,7 +56,7 @@
 @interface B () {
   int b;
   static_assert(sizeof(b) == 4, "");
-  static_assert(sizeof(b) == 3, ""); // expected-error {{static_assert failed}}
+  static_assert(sizeof(b) == 3, ""); // expected-error {{static assertion failed}}
 }
 @end
 
@@ -71,7 +71,7 @@
   int a;
   static_assert(1, ""); // expected-error {{type name requires a specifier or qualifier}} expected-error{{expected parameter declarator}} expected-error {{expected ')'}} expected-note {{to match this '('}}
   _Static_assert(1, "");
-  _Static_assert(0, ""); // expected-error {{static_assert failed}}
+  _Static_assert(0, ""); // expected-error {{static assertion failed}}
 }
 @end
 #endif
diff --git a/clang/test/Sema/builtin-align.c b/clang/test/Sema/builtin-align.c
--- a/clang/test/Sema/builtin-align.c
+++ b/clang/test/Sema/builtin-align.c
@@ -113,8 +113,8 @@
   _Static_assert(__builtin_align_down(33, 32) == 32, "");
 
   // But not if one of the arguments isn't constant:
-  _Static_assert(ALIGN_BUILTIN(33, x) != 100, ""); // expected-error {{static_assert expression is not an integral constant expression}}
-  _Static_assert(ALIGN_BUILTIN(x, 4) != 100, "");  // expected-error {{static_assert expression is not an integral constant expression}}
+  _Static_assert(ALIGN_BUILTIN(33, x) != 100, ""); // expected-error {{static assertion expression is not an integral constant expression}}
+  _Static_assert(ALIGN_BUILTIN(x, 4) != 100, "");  // expected-error {{static assertion expression is not an integral constant expression}}
 }
 
 // Check that it is a constant expression that can be assigned to globals:
diff --git a/clang/test/Sema/sizeless-1.c b/clang/test/Sema/sizeless-1.c
--- a/clang/test/Sema/sizeless-1.c
+++ b/clang/test/Sema/sizeless-1.c
@@ -69,7 +69,7 @@
   // Using pointers to sizeless data isn't wrong here, but because the
   // type is incomplete, it doesn't provide any alignment guarantees.
   _Static_assert(__atomic_is_lock_free(1, &local_int8) == __atomic_is_lock_free(1, incomplete_ptr), "");
-  _Static_assert(__atomic_is_lock_free(2, &local_int8) == __atomic_is_lock_free(2, incomplete_ptr), ""); // expected-error {{static_assert expression is not an integral constant expression}}
+  _Static_assert(__atomic_is_lock_free(2, &local_int8) == __atomic_is_lock_free(2, incomplete_ptr), ""); // expected-error {{static assertion expression is not an integral constant expression}}
   _Static_assert(__atomic_always_lock_free(1, &local_int8) == __atomic_always_lock_free(1, incomplete_ptr), "");
 
   local_int8; // expected-warning {{expression result unused}}
diff --git a/clang/test/Sema/static-assert.c b/clang/test/Sema/static-assert.c
--- a/clang/test/Sema/static-assert.c
+++ b/clang/test/Sema/static-assert.c
@@ -5,11 +5,11 @@
 
 _Static_assert("foo", "string is nonzero"); // ext-warning {{'_Static_assert' is a C11 extension}}
 #ifndef __cplusplus
-// expected-error@-2 {{static_assert expression is not an integral constant expression}}
+// expected-error@-2 {{static assertion expression is not an integral constant expression}}
 #endif
 
 _Static_assert(1, "1 is nonzero"); // ext-warning {{'_Static_assert' is a C11 extension}}
-_Static_assert(0, "0 is nonzero"); // expected-error {{static_assert failed: 0 is nonzero}} \
+_Static_assert(0, "0 is nonzero"); // expected-error {{static assertion failed: 0 is nonzero}} \
                                    // ext-warning {{'_Static_assert' is a C11 extension}}
 
 #ifdef MS
@@ -18,7 +18,7 @@
 
 void foo(void) {
   _Static_assert(1, "1 is nonzero"); // ext-warning {{'_Static_assert' is a C11 extension}}
-  _Static_assert(0, "0 is nonzero"); // expected-error {{static_assert failed: 0 is nonzero}} \
+  _Static_assert(0, "0 is nonzero"); // expected-error {{static assertion failed: 0 is nonzero}} \
                                      // ext-warning {{'_Static_assert' is a C11 extension}}
 #ifdef MS
   static_assert(1, "1 is nonzero"); // ms-warning {{use of 'static_assert' without}}
@@ -31,7 +31,7 @@
 struct A {
   int a;
   _Static_assert(1, "1 is nonzero"); // ext-warning {{'_Static_assert' is a C11 extension}}
-  _Static_assert(0, "0 is nonzero"); // expected-error {{static_assert failed: 0 is nonzero}} \
+  _Static_assert(0, "0 is nonzero"); // expected-error {{static assertion failed: 0 is nonzero}} \
                                      // ext-warning {{'_Static_assert' is a C11 extension}}
 #ifdef MS
   static_assert(1, "1 is nonzero"); // ms-warning {{use of 'static_assert' without}}
@@ -54,7 +54,7 @@
 
 typedef UNION(unsigned, struct A) U1; // ext-warning 3 {{'_Static_assert' is a C11 extension}}
 UNION(char[2], short) u2 = { .one = { 'a', 'b' } }; // ext-warning 3 {{'_Static_assert' is a C11 extension}} cxx-warning {{designated initializers are a C++20 extension}}
-typedef UNION(char, short) U3; // expected-error {{static_assert failed due to requirement 'sizeof(char) == sizeof(short)': type size mismatch}} \
+typedef UNION(char, short) U3; // expected-error {{static assertion failed due to requirement 'sizeof(char) == sizeof(short)': type size mismatch}} \
                                // ext-warning 3 {{'_Static_assert' is a C11 extension}}
 typedef UNION(float, 0.5f) U4; // expected-error {{expected a type}} \
                                // ext-warning 3 {{'_Static_assert' is a C11 extension}}
diff --git a/clang/test/SemaCXX/access-base-class.cpp b/clang/test/SemaCXX/access-base-class.cpp
--- a/clang/test/SemaCXX/access-base-class.cpp
+++ b/clang/test/SemaCXX/access-base-class.cpp
@@ -109,7 +109,7 @@
 
 template <int>
 struct Impossible {
-  static_assert(false, ""); // expected-error {{static_assert failed}}
+  static_assert(false, ""); // expected-error {{static assertion failed}}
 };
 
 // verify "no member named 'value'" bogus diagnostic is not emitted.
diff --git a/clang/test/SemaCXX/alias-template.cpp b/clang/test/SemaCXX/alias-template.cpp
--- a/clang/test/SemaCXX/alias-template.cpp
+++ b/clang/test/SemaCXX/alias-template.cpp
@@ -174,7 +174,7 @@
   using T = X[J];
   using U = T<I>;
 };
-static_assert(__is_same(S<3>::U, X[2]), ""); // expected-error {{static_assert failed}}
+static_assert(__is_same(S<3>::U, X[2]), ""); // expected-error {{static assertion failed}}
 }
 
 namespace PR39623 {
diff --git a/clang/test/SemaCXX/builtin-is-constant-evaluated.cpp b/clang/test/SemaCXX/builtin-is-constant-evaluated.cpp
--- a/clang/test/SemaCXX/builtin-is-constant-evaluated.cpp
+++ b/clang/test/SemaCXX/builtin-is-constant-evaluated.cpp
@@ -26,7 +26,7 @@
 constexpr int bn = __builtin_is_constant_evaluated() ? dummy : 42; // expected-note {{non-const variable 'dummy' is not allowed}}
 
 const int n2 = __builtin_is_constant_evaluated() ? dummy : 42; // expected-note {{declared here}}
-static_assert(n2 == 42);                                       // expected-error {{static_assert expression is not an integral constant}}
+static_assert(n2 == 42);                                       // expected-error {{static assertion expression is not an integral constant}}
 // expected-note@-1 {{initializer of 'n2' is not a constant expression}}
 
 template <bool V, bool Default = std::is_constant_evaluated()>
diff --git a/clang/test/SemaCXX/builtin-std-move.cpp b/clang/test/SemaCXX/builtin-std-move.cpp
--- a/clang/test/SemaCXX/builtin-std-move.cpp
+++ b/clang/test/SemaCXX/builtin-std-move.cpp
@@ -39,7 +39,7 @@
     return static_cast<T&&>(x);
   }
   template<typename T> CONSTEXPR T &&forward(typename remove_reference<T>::type &&x) {
-    static_assert(!is_lvalue_reference<T>::value, "should not forward rval as lval"); // expected-error {{static_assert failed}}
+    static_assert(!is_lvalue_reference<T>::value, "should not forward rval as lval"); // expected-error {{static assertion failed}}
     return static_cast<T&&>(x);
   }
 
diff --git a/clang/test/SemaCXX/builtins.cpp b/clang/test/SemaCXX/builtins.cpp
--- a/clang/test/SemaCXX/builtins.cpp
+++ b/clang/test/SemaCXX/builtins.cpp
@@ -47,7 +47,7 @@
 void a(void) {}
 int n;
 void *p = __builtin_function_start(n);               // expected-error {{argument must be a function}}
-static_assert(__builtin_function_start(a) == a, ""); // expected-error {{static_assert expression is not an integral constant expression}}
+static_assert(__builtin_function_start(a) == a, ""); // expected-error {{static assertion expression is not an integral constant expression}}
 } // namespace function_start
 
 void no_ms_builtins() {
diff --git a/clang/test/SemaCXX/complex-folding.cpp b/clang/test/SemaCXX/complex-folding.cpp
--- a/clang/test/SemaCXX/complex-folding.cpp
+++ b/clang/test/SemaCXX/complex-folding.cpp
@@ -3,7 +3,7 @@
 // Test the constant folding of builtin complex numbers.
 
 static_assert((0.0 + 0.0j) == (0.0 + 0.0j));
-static_assert((0.0 + 0.0j) != (0.0 + 0.0j)); // expected-error {{static_assert}}
+static_assert((0.0 + 0.0j) != (0.0 + 0.0j)); // expected-error {{static assertion}}
 
 static_assert((0.0 + 0.0j) == 0.0);
 static_assert(0.0 == (0.0 + 0.0j));
@@ -14,21 +14,21 @@
 
 // Walk around the complex plane stepping between angular differences and
 // equality.
-static_assert((1.0 + 0.0j) == (0.0 + 0.0j)); // expected-error {{static_assert}}
+static_assert((1.0 + 0.0j) == (0.0 + 0.0j)); // expected-error {{static assertion}}
 static_assert((1.0 + 0.0j) == (1.0 + 0.0j));
-static_assert((1.0 + 1.0j) == (1.0 + 0.0j)); // expected-error {{static_assert}}
+static_assert((1.0 + 1.0j) == (1.0 + 0.0j)); // expected-error {{static assertion}}
 static_assert((1.0 + 1.0j) == (1.0 + 1.0j));
-static_assert((0.0 + 1.0j) == (1.0 + 1.0j)); // expected-error {{static_assert}}
+static_assert((0.0 + 1.0j) == (1.0 + 1.0j)); // expected-error {{static assertion}}
 static_assert((0.0 + 1.0j) == (0.0 + 1.0j));
-static_assert((-1.0 + 1.0j) == (0.0 + 1.0j)); // expected-error {{static_assert}}
+static_assert((-1.0 + 1.0j) == (0.0 + 1.0j)); // expected-error {{static assertion}}
 static_assert((-1.0 + 1.0j) == (-1.0 + 1.0j));
-static_assert((-1.0 + 0.0j) == (-1.0 + 1.0j)); // expected-error {{static_assert}}
+static_assert((-1.0 + 0.0j) == (-1.0 + 1.0j)); // expected-error {{static assertion}}
 static_assert((-1.0 + 0.0j) == (-1.0 + 0.0j));
-static_assert((-1.0 - 1.0j) == (-1.0 + 0.0j)); // expected-error {{static_assert}}
+static_assert((-1.0 - 1.0j) == (-1.0 + 0.0j)); // expected-error {{static assertion}}
 static_assert((-1.0 - 1.0j) == (-1.0 - 1.0j));
-static_assert((0.0 - 1.0j) == (-1.0 - 1.0j)); // expected-error {{static_assert}}
+static_assert((0.0 - 1.0j) == (-1.0 - 1.0j)); // expected-error {{static assertion}}
 static_assert((0.0 - 1.0j) == (0.0 - 1.0j));
-static_assert((1.0 - 1.0j) == (0.0 - 1.0j)); // expected-error {{static_assert}}
+static_assert((1.0 - 1.0j) == (0.0 - 1.0j)); // expected-error {{static assertion}}
 static_assert((1.0 - 1.0j) == (1.0 - 1.0j));
 
 // Test basic mathematical folding of both complex and real operands.
diff --git a/clang/test/SemaCXX/constant-expression-cxx11.cpp b/clang/test/SemaCXX/constant-expression-cxx11.cpp
--- a/clang/test/SemaCXX/constant-expression-cxx11.cpp
+++ b/clang/test/SemaCXX/constant-expression-cxx11.cpp
@@ -580,7 +580,7 @@
   return (&p)[64]; // expected-note {{cannot refer to element 64 of array of 2 elements}}
 }
 static_assert(fail(*(&(&(*(*&(&zs[2] - 1)[0] + 2 - 2))[2])[-1][2] - 2)) == 11, ""); // \
-expected-error {{static_assert expression is not an integral constant expression}} \
+expected-error {{static assertion expression is not an integral constant expression}} \
 expected-note {{in call to 'fail(zs[1][0][1][0])'}}
 
 constexpr int arr[40] = { 1, 2, 3, [8] = 4 };
@@ -1596,11 +1596,11 @@
   // Matching GCC, file-scope array compound literals initialized by constants
   // are lifetime-extended.
   constexpr int *p = (int*)(int[1]){3}; // expected-warning {{C99}}
-  static_assert(*p == 3, "");           // expected-error {{static_assert expression is not an integral constant expression}}
+  static_assert(*p == 3, "");           // expected-error {{static assertion expression is not an integral constant expression}}
                                         // expected-note@-1 {{subexpression not valid}}
                                         // expected-note@-3 {{declared here}}
   static_assert((int[2]){1, 2}[1] == 2, ""); // expected-warning {{C99}}
-  // expected-error@-1 {{static_assert expression is not an integral constant expression}}
+  // expected-error@-1 {{static assertion expression is not an integral constant expression}}
   // expected-note@-2 {{subexpression not valid}}
   // expected-note@-3 {{declared here}}
 
@@ -1912,12 +1912,12 @@
   static_assert(p->f() == sizeof(X<S1>), "");
   // cxx11-error@-1    {{not an integral constant expression}}
   // cxx11-note@-2     {{call to virtual function}}
-  // cxx20_2b-error@-3 {{static_assert failed}}
+  // cxx20_2b-error@-3 {{static assertion failed}}
 
   // Non-virtual f(), OK.
   constexpr X<X<S2>> xxs2;
   constexpr X<S2> *q = const_cast<X<X<S2>>*>(&xxs2);
-  static_assert(q->f() == sizeof(S2), ""); // cxx20_2b-error {{static_assert failed}}
+  static_assert(q->f() == sizeof(S2), ""); // cxx20_2b-error {{static assertion failed}}
 }
 
 namespace ConstexprConstructorRecovery {
diff --git a/clang/test/SemaCXX/constexpr-builtin-bit-cast.cpp b/clang/test/SemaCXX/constexpr-builtin-bit-cast.cpp
--- a/clang/test/SemaCXX/constexpr-builtin-bit-cast.cpp
+++ b/clang/test/SemaCXX/constexpr-builtin-bit-cast.cpp
@@ -446,7 +446,7 @@
 }
 
 static_assert(f(/*read_uninit=*/false), "");
-static_assert(f(/*read_uninit=*/true), ""); // expected-error{{static_assert expression is not an integral constant expression}} expected-note{{in call to 'f(true)'}}
+static_assert(f(/*read_uninit=*/true), ""); // expected-error{{static assertion expression is not an integral constant expression}} expected-note{{in call to 'f(true)'}}
 
 constexpr bytes ld539 = {
   0x0, 0x0,  0x0,  0x0,
diff --git a/clang/test/SemaCXX/constexpr-function-recovery-crash.cpp b/clang/test/SemaCXX/constexpr-function-recovery-crash.cpp
--- a/clang/test/SemaCXX/constexpr-function-recovery-crash.cpp
+++ b/clang/test/SemaCXX/constexpr-function-recovery-crash.cpp
@@ -68,7 +68,7 @@
 }
 
 constexpr int test10() { return undef(); } // expected-error {{use of undeclared identifier 'undef'}}
-static_assert(test10() <= 1, "should not crash"); // expected-error {{static_assert expression is not an integral constant expression}}
+static_assert(test10() <= 1, "should not crash"); // expected-error {{static assertion expression is not an integral constant expression}}
 
 struct X {} array[] = {undef()}; // expected-error {{use of undeclared identifier 'undef'}}
 constexpr void test11() {
diff --git a/clang/test/SemaCXX/coroutines-exp-namespace.cpp b/clang/test/SemaCXX/coroutines-exp-namespace.cpp
--- a/clang/test/SemaCXX/coroutines-exp-namespace.cpp
+++ b/clang/test/SemaCXX/coroutines-exp-namespace.cpp
@@ -1109,8 +1109,8 @@
 
   CoroMemberTag test_asserts(int *) const {
     auto TC = co_yield 0;
-    static_assert(TC.MatchesArgs<const TestType &>, ""); // expected-error {{static_assert failed}}
-    static_assert(TC.MatchesArgs<const TestType &>, ""); // expected-error {{static_assert failed}}
+    static_assert(TC.MatchesArgs<const TestType &>, ""); // expected-error {{static assertion failed}}
+    static_assert(TC.MatchesArgs<const TestType &>, ""); // expected-error {{static assertion failed}}
     static_assert(TC.MatchesArgs<const TestType &, int *>, "");
   }
 
@@ -1201,8 +1201,8 @@
 
   CoroMemberTag test_asserts(int *) const {
     auto TC = co_yield 0;
-    static_assert(TC.template MatchesArgs<const DepTestType &>, ""); // expected-error {{static_assert failed}}
-    static_assert(TC.template MatchesArgs<>, "");                    // expected-error {{static_assert failed}}
+    static_assert(TC.template MatchesArgs<const DepTestType &>, ""); // expected-error {{static assertion failed}}
+    static_assert(TC.template MatchesArgs<>, "");                    // expected-error {{static assertion failed}}
     static_assert(TC.template MatchesArgs<const DepTestType &, int *>, "");
   }
 
@@ -1265,7 +1265,7 @@
     static_assert(!TCT::MatchesArgs<DepTestType *>, "");
 
     // Ensure diagnostics are actually being generated here
-    static_assert(TCT::MatchesArgs<int>, ""); // expected-error {{static_assert failed}}
+    static_assert(TCT::MatchesArgs<int>, ""); // expected-error {{static assertion failed}}
   }
 
   static CoroMemberTag test_static(volatile void *const, char &&) {
diff --git a/clang/test/SemaCXX/coroutines.cpp b/clang/test/SemaCXX/coroutines.cpp
--- a/clang/test/SemaCXX/coroutines.cpp
+++ b/clang/test/SemaCXX/coroutines.cpp
@@ -1130,8 +1130,8 @@
 
   CoroMemberTag test_asserts(int *) const {
     auto TC = co_yield 0;
-    static_assert(TC.MatchesArgs<const TestType &>, ""); // expected-error {{static_assert failed}}
-    static_assert(TC.MatchesArgs<const TestType &>, ""); // expected-error {{static_assert failed}}
+    static_assert(TC.MatchesArgs<const TestType &>, ""); // expected-error {{static assertion failed}}
+    static_assert(TC.MatchesArgs<const TestType &>, ""); // expected-error {{static assertion failed}}
     static_assert(TC.MatchesArgs<const TestType &, int *>, "");
   }
 
@@ -1222,8 +1222,8 @@
 
   CoroMemberTag test_asserts(int *) const {
     auto TC = co_yield 0;
-    static_assert(TC.template MatchesArgs<const DepTestType &>, ""); // expected-error {{static_assert failed}}
-    static_assert(TC.template MatchesArgs<>, ""); // expected-error {{static_assert failed}}
+    static_assert(TC.template MatchesArgs<const DepTestType &>, ""); // expected-error {{static assertion failed}}
+    static_assert(TC.template MatchesArgs<>, ""); // expected-error {{static assertion failed}}
     static_assert(TC.template MatchesArgs<const DepTestType &, int *>, "");
   }
 
@@ -1286,7 +1286,7 @@
     static_assert(!TCT::MatchesArgs<DepTestType *>, "");
 
     // Ensure diagnostics are actually being generated here
-    static_assert(TCT::MatchesArgs<int>, ""); // expected-error {{static_assert failed}}
+    static_assert(TCT::MatchesArgs<int>, ""); // expected-error {{static assertion failed}}
   }
 
   static CoroMemberTag test_static(volatile void *const, char &&) {
diff --git a/clang/test/SemaCXX/cxx2a-template-lambdas.cpp b/clang/test/SemaCXX/cxx2a-template-lambdas.cpp
--- a/clang/test/SemaCXX/cxx2a-template-lambdas.cpp
+++ b/clang/test/SemaCXX/cxx2a-template-lambdas.cpp
@@ -11,19 +11,19 @@
 
 void func() {
   auto L0 = []<typename T>(T arg) {
-    static_assert(is_same<T, int>); // expected-error {{static_assert failed}}
+    static_assert(is_same<T, int>); // expected-error {{static assertion failed}}
   };
   L0(0);
   L0(0.0); // expected-note {{in instantiation}}
 
   auto L1 = []<int I> {
-    static_assert(I == 5); // expected-error {{static_assert failed}}
+    static_assert(I == 5); // expected-error {{static assertion failed}}
   };
   L1.operator()<5>();
   L1.operator()<6>(); // expected-note {{in instantiation}}
 
   auto L2 = []<template<typename> class T, class U>(T<U> &&arg) {
-    static_assert(is_same<T<U>, DummyTemplate<float>>); // // expected-error {{static_assert failed}}
+    static_assert(is_same<T<U>, DummyTemplate<float>>); // // expected-error {{static assertion failed}}
   };
   L2(DummyTemplate<float>());
   L2(DummyTemplate<double>()); // expected-note {{in instantiation}}
diff --git a/clang/test/SemaCXX/delete-and-function-templates.cpp b/clang/test/SemaCXX/delete-and-function-templates.cpp
--- a/clang/test/SemaCXX/delete-and-function-templates.cpp
+++ b/clang/test/SemaCXX/delete-and-function-templates.cpp
@@ -12,7 +12,7 @@
 template<class T> double f(T) = delete; //expected-note{{candidate}}
 char f(...); //expected-note{{candidate}}
 
-static_assert(is_same<decltype(f(3)),char>::value, ""); //expected-error{{call to deleted function}} expected-error{{static_assert failed}}
+static_assert(is_same<decltype(f(3)),char>::value, ""); //expected-error{{call to deleted function}} expected-error{{static assertion failed}}
 
 template<class T> decltype(f(T{})) g(T); // this one sfinae's out.
 template<class T> int *g(T);
diff --git a/clang/test/SemaCXX/int-ptr-cast-SFINAE.cpp b/clang/test/SemaCXX/int-ptr-cast-SFINAE.cpp
--- a/clang/test/SemaCXX/int-ptr-cast-SFINAE.cpp
+++ b/clang/test/SemaCXX/int-ptr-cast-SFINAE.cpp
@@ -19,4 +19,4 @@
 template<typename T>
 static const auto has_minus_assign = decltype(test<T>())::value;
 
-static_assert(has_minus_assign<int*>, "failed"); // expected-error {{static_assert failed due to requirement 'has_minus_assign<int *>': failed}}
+static_assert(has_minus_assign<int*>, "failed"); // expected-error {{static assertion failed due to requirement 'has_minus_assign<int *>': failed}}
diff --git a/clang/test/SemaCXX/recovery-expr-type.cpp b/clang/test/SemaCXX/recovery-expr-type.cpp
--- a/clang/test/SemaCXX/recovery-expr-type.cpp
+++ b/clang/test/SemaCXX/recovery-expr-type.cpp
@@ -149,7 +149,7 @@
   Circular_A = Circular(1), // expected-error {{'test13::Circular' is an incomplete type}}
 };
 // Enumerators can be evaluated (they evaluate as zero, but we don't care).
-static_assert(Circular_A == 0 && Circular_A != 0, ""); // expected-error {{static_assert failed}}
+static_assert(Circular_A == 0 && Circular_A != 0, ""); // expected-error {{static assertion failed}}
 }
 
 namespace test14 {
diff --git a/clang/test/SemaCXX/sizeless-1.cpp b/clang/test/SemaCXX/sizeless-1.cpp
--- a/clang/test/SemaCXX/sizeless-1.cpp
+++ b/clang/test/SemaCXX/sizeless-1.cpp
@@ -78,7 +78,7 @@
   // Using pointers to sizeless data isn't wrong here, but because the
   // type is incomplete, it doesn't provide any alignment guarantees.
   _Static_assert(__atomic_is_lock_free(1, &local_int8) == __atomic_is_lock_free(1, incomplete_ptr), "");
-  _Static_assert(__atomic_is_lock_free(2, &local_int8) == __atomic_is_lock_free(2, incomplete_ptr), ""); // expected-error {{static_assert expression is not an integral constant expression}}
+  _Static_assert(__atomic_is_lock_free(2, &local_int8) == __atomic_is_lock_free(2, incomplete_ptr), ""); // expected-error {{static assertion expression is not an integral constant expression}}
   _Static_assert(__atomic_always_lock_free(1, &local_int8) == __atomic_always_lock_free(1, incomplete_ptr), "");
 
   local_int8; // expected-warning {{expression result unused}}
diff --git a/clang/test/SemaCXX/static-assert-cxx17.cpp b/clang/test/SemaCXX/static-assert-cxx17.cpp
--- a/clang/test/SemaCXX/static-assert-cxx17.cpp
+++ b/clang/test/SemaCXX/static-assert-cxx17.cpp
@@ -22,7 +22,7 @@
 template <typename U, typename V>
 void foo() {
   static_assert(S1<U, V>::value);
-  // expected-error@-1{{static_assert failed due to requirement 'S1<int, float>::value'}}
+  // expected-error@-1{{static assertion failed due to requirement 'S1<int, float>::value'}}
 }
 template void foo<int, float>();
 // expected-note@-1{{in instantiation of function template specialization 'foo<int, float>' requested here}}
@@ -30,7 +30,7 @@
 template <typename U, typename V>
 void foo2() {
   static_assert(global_inline_var<U, V>);
-  // expected-error@-1{{static_assert failed due to requirement 'global_inline_var<int, float>'}}
+  // expected-error@-1{{static assertion failed due to requirement 'global_inline_var<int, float>'}}
 }
 template void foo2<int, float>();
 // expected-note@-1{{in instantiation of function template specialization 'foo2<int, float>' requested here}}
@@ -38,7 +38,7 @@
 template <typename T, typename U, typename V>
 void foo3() {
   static_assert(T::template var<U, V>);
-  // expected-error@-1{{static_assert failed due to requirement 'S2<long>::var<int, float>'}}
+  // expected-error@-1{{static assertion failed due to requirement 'S2<long>::var<int, float>'}}
 }
 template void foo3<S2<long>, int, float>();
 // expected-note@-1{{in instantiation of function template specialization 'foo3<S2<long>, int, float>' requested here}}
@@ -46,7 +46,7 @@
 template <typename T>
 void foo4() {
   static_assert(S1<T[sizeof(T)], int[4]>::value, "");
-  // expected-error@-1{{static_assert failed due to requirement 'S1<float[4], int[4]>::value'}}
+  // expected-error@-1{{static assertion failed due to requirement 'S1<float[4], int[4]>::value'}}
 };
 template void foo4<float>();
 // expected-note@-1{{in instantiation of function template specialization 'foo4<float>' requested here}}
@@ -55,7 +55,7 @@
 template <typename U, typename V>
 void foo5() {
   static_assert(!!(global_inline_var<U, V>));
-  // expected-error@-1{{static_assert failed due to requirement '!!(global_inline_var<int, float>)'}}
+  // expected-error@-1{{static assertion failed due to requirement '!!(global_inline_var<int, float>)'}}
 }
 template void foo5<int, float>();
 // expected-note@-1{{in instantiation of function template specialization 'foo5<int, float>' requested here}}
@@ -76,29 +76,29 @@
 template <class T>
 void foo6() {
   static_assert(X<typename T::T>());
-  // expected-error@-1{{static_assert failed due to requirement 'X<int>()'}}
+  // expected-error@-1{{static assertion failed due to requirement 'X<int>()'}}
   static_assert(X<typename T::T>{});
-  // expected-error@-1{{static_assert failed due to requirement 'X<int>{}'}}
+  // expected-error@-1{{static assertion failed due to requirement 'X<int>{}'}}
   static_assert(X<typename T::T>{1, 2});
-  // expected-error@-1{{static_assert failed due to requirement 'X<int>{1, 2}'}}
+  // expected-error@-1{{static assertion failed due to requirement 'X<int>{1, 2}'}}
   static_assert(X<typename T::T>({1, 2}));
-  // expected-error@-1{{static_assert failed due to requirement 'X<int>({1, 2})'}}
+  // expected-error@-1{{static assertion failed due to requirement 'X<int>({1, 2})'}}
   static_assert(typename T::T{0});
-  // expected-error@-1{{static_assert failed due to requirement 'int{0}'}}
+  // expected-error@-1{{static assertion failed due to requirement 'int{0}'}}
   static_assert(typename T::T(0));
-  // expected-error@-1{{static_assert failed due to requirement 'int(0)'}}
+  // expected-error@-1{{static assertion failed due to requirement 'int(0)'}}
   static_assert(sizeof(X<typename T::T>) == 0);
-  // expected-error@-1{{static_assert failed due to requirement 'sizeof(X<int>) == 0'}}
+  // expected-error@-1{{static assertion failed due to requirement 'sizeof(X<int>) == 0'}}
   static_assert((const X<typename T::T> *)nullptr);
-  // expected-error@-1{{static_assert failed due to requirement '(const X<int> *)nullptr'}}
+  // expected-error@-1{{static assertion failed due to requirement '(const X<int> *)nullptr'}}
   static_assert(static_cast<const X<typename T::T> *>(nullptr));
-  // expected-error@-1{{static_assert failed due to requirement 'static_cast<const X<int> *>(nullptr)'}}
+  // expected-error@-1{{static assertion failed due to requirement 'static_cast<const X<int> *>(nullptr)'}}
   static_assert((const X<typename T::T>[]){} == nullptr);
-  // expected-error@-1{{static_assert failed due to requirement '(const X<int>[0]){} == nullptr'}}
+  // expected-error@-1{{static assertion failed due to requirement '(const X<int>[0]){} == nullptr'}}
   static_assert(sizeof(X<decltype(X<typename T::T>().X<typename T::T>::~X())>) == 0);
-  // expected-error@-1{{static_assert failed due to requirement 'sizeof(X<void>) == 0'}}
+  // expected-error@-1{{static assertion failed due to requirement 'sizeof(X<void>) == 0'}}
   static_assert(constexpr_return_false<typename T::T, typename T::U>());
-  // expected-error@-1{{static_assert failed due to requirement 'constexpr_return_false<int, float>()'}}
+  // expected-error@-1{{static assertion failed due to requirement 'constexpr_return_false<int, float>()'}}
 }
 template void foo6<ExampleTypes>();
 // expected-note@-1{{in instantiation of function template specialization 'foo6<ExampleTypes>' requested here}}
diff --git a/clang/test/SemaCXX/static-assert.cpp b/clang/test/SemaCXX/static-assert.cpp
--- a/clang/test/SemaCXX/static-assert.cpp
+++ b/clang/test/SemaCXX/static-assert.cpp
@@ -2,61 +2,61 @@
 
 int f(); // expected-note {{declared here}}
 
-static_assert(f(), "f"); // expected-error {{static_assert expression is not an integral constant expression}} expected-note {{non-constexpr function 'f' cannot be used in a constant expression}}
+static_assert(f(), "f"); // expected-error {{static assertion expression is not an integral constant expression}} expected-note {{non-constexpr function 'f' cannot be used in a constant expression}}
 static_assert(true, "true is not false");
-static_assert(false, "false is false"); // expected-error {{static_assert failed: false is false}}
+static_assert(false, "false is false"); // expected-error {{static assertion failed: false is false}}
 
 void g() {
-    static_assert(false, "false is false"); // expected-error {{static_assert failed: false is false}}
+    static_assert(false, "false is false"); // expected-error {{static assertion failed: false is false}}
 }
 
 class C {
-    static_assert(false, "false is false"); // expected-error {{static_assert failed: false is false}}
+    static_assert(false, "false is false"); // expected-error {{static assertion failed: false is false}}
 };
 
 template<int N> struct T {
-    static_assert(N == 2, "N is not 2!"); // expected-error {{static_assert failed due to requirement '1 == 2': N is not 2!}}
+    static_assert(N == 2, "N is not 2!"); // expected-error {{static assertion failed due to requirement '1 == 2': N is not 2!}}
 };
 
 T<1> t1; // expected-note {{in instantiation of template class 'T<1>' requested here}}
 T<2> t2;
 
 template<typename T> struct S {
-    static_assert(sizeof(T) > sizeof(char), "Type not big enough!"); // expected-error {{static_assert failed due to requirement 'sizeof(char) > sizeof(char)': Type not big enough!}}
+    static_assert(sizeof(T) > sizeof(char), "Type not big enough!"); // expected-error {{static assertion failed due to requirement 'sizeof(char) > sizeof(char)': Type not big enough!}}
 };
 
 S<char> s1; // expected-note {{in instantiation of template class 'S<char>' requested here}}
 S<int> s2;
 
-static_assert(false, L"\xFFFFFFFF"); // expected-error {{static_assert failed: L"\xFFFFFFFF"}}
-static_assert(false, u"\U000317FF"); // expected-error {{static_assert failed: u"\U000317FF"}}
+static_assert(false, L"\xFFFFFFFF"); // expected-error {{static assertion failed: L"\xFFFFFFFF"}}
+static_assert(false, u"\U000317FF"); // expected-error {{static assertion failed: u"\U000317FF"}}
 
-static_assert(false, u8"Ω"); // expected-error {{static_assert failed: u8"\316\251"}}
-static_assert(false, L"\u1234"); // expected-error {{static_assert failed: L"\x1234"}}
-static_assert(false, L"\x1ff" "0\x123" "fx\xfffff" "goop"); // expected-error {{static_assert failed: L"\x1FF""0\x123""fx\xFFFFFgoop"}}
+static_assert(false, u8"Ω"); // expected-error {{static assertion failed: u8"\316\251"}}
+static_assert(false, L"\u1234"); // expected-error {{static assertion failed: L"\x1234"}}
+static_assert(false, L"\x1ff" "0\x123" "fx\xfffff" "goop"); // expected-error {{static assertion failed: L"\x1FF""0\x123""fx\xFFFFFgoop"}}
 
 static_assert(false, R"(a
 \tb
 c
-)"); // expected-error@-3 {{static_assert failed: a\n\tb\nc\n}}
+)"); // expected-error@-3 {{static assertion failed: a\n\tb\nc\n}}
 
 static_assert(false, "\u0080\u0081\u0082\u0083\u0099\u009A\u009B\u009C\u009D\u009E\u009F");
-// expected-error@-1 {{static_assert failed: <U+0080><U+0081><U+0082><U+0083><U+0099><U+009A><U+009B><U+009C><U+009D><U+009E><U+009F>}}
+// expected-error@-1 {{static assertion failed: <U+0080><U+0081><U+0082><U+0083><U+0099><U+009A><U+009B><U+009C><U+009D><U+009E><U+009F>}}
 
 //! Contains RTL/LTR marks
-static_assert(false, "\u200Eabc\u200Fdef\u200Fgh"); // expected-error {{static_assert failed: ‎abc‏def‏gh}}
+static_assert(false, "\u200Eabc\u200Fdef\u200Fgh"); // expected-error {{static assertion failed: ‎abc‏def‏gh}}
 
 //! Contains ZWJ/regional indicators
-static_assert(false, "🏳️‍🌈 🏴󠁧󠁢󠁥󠁮󠁧󠁿 🇪🇺"); // expected-error {{static_assert failed: 🏳️‍🌈 🏴󠁧󠁢󠁥󠁮󠁧󠁿 🇪🇺}}
+static_assert(false, "🏳️‍🌈 🏴󠁧󠁢󠁥󠁮󠁧󠁿 🇪🇺"); // expected-error {{static assertion failed: 🏳️‍🌈 🏴󠁧󠁢󠁥󠁮󠁧󠁿 🇪🇺}}
 
 template<typename T> struct AlwaysFails {
   // Only give one error here.
-  static_assert(false, ""); // expected-error {{static_assert failed}}
+  static_assert(false, ""); // expected-error {{static assertion failed}}
 };
 AlwaysFails<int> alwaysFails;
 
 template<typename T> struct StaticAssertProtected {
-  static_assert(__is_literal(T), ""); // expected-error {{static_assert failed}}
+  static_assert(__is_literal(T), ""); // expected-error {{static assertion failed}}
   static constexpr T t = {}; // no error here
 };
 struct X { ~X(); };
@@ -81,7 +81,7 @@
   static const bool value = false;
 };
 
-static_assert(first_trait<X>::value && second_trait<X>::value, "message"); // expected-error{{static_assert failed due to requirement 'second_trait<X>::value': message}}
+static_assert(first_trait<X>::value && second_trait<X>::value, "message"); // expected-error{{static assertion failed due to requirement 'second_trait<X>::value': message}}
 
 namespace std {
 
@@ -125,29 +125,29 @@
 };
 
 static_assert(std::is_same<ExampleTypes::T, ExampleTypes::U>::value, "message");
-// expected-error@-1{{static_assert failed due to requirement 'std::is_same<int, float>::value': message}}
+// expected-error@-1{{static assertion failed due to requirement 'std::is_same<int, float>::value': message}}
 static_assert(std::is_const<ExampleTypes::T>::value, "message");
-// expected-error@-1{{static_assert failed due to requirement 'std::is_const<int>::value': message}}
+// expected-error@-1{{static assertion failed due to requirement 'std::is_const<int>::value': message}}
 static_assert(!std::is_const<const ExampleTypes::T>::value, "message");
-// expected-error@-1{{static_assert failed due to requirement '!std::is_const<const int>::value': message}}
+// expected-error@-1{{static assertion failed due to requirement '!std::is_const<const int>::value': message}}
 static_assert(!(std::is_const<const ExampleTypes::T>::value), "message");
-// expected-error@-1{{static_assert failed due to requirement '!(std::is_const<const int>::value)': message}}
+// expected-error@-1{{static assertion failed due to requirement '!(std::is_const<const int>::value)': message}}
 static_assert(std::is_const<const ExampleTypes::T>::value == false, "message");
-// expected-error@-1{{static_assert failed due to requirement 'std::is_const<const int>::value == false': message}}
+// expected-error@-1{{static assertion failed due to requirement 'std::is_const<const int>::value == false': message}}
 static_assert(!(std::is_const<const ExampleTypes::T>::value == true), "message");
-// expected-error@-1{{static_assert failed due to requirement '!(std::is_const<const int>::value == true)': message}}
+// expected-error@-1{{static assertion failed due to requirement '!(std::is_const<const int>::value == true)': message}}
 static_assert(std::is_const<ExampleTypes::T>(), "message");
-// expected-error@-1{{static_assert failed due to requirement 'std::is_const<int>()': message}}
+// expected-error@-1{{static assertion failed due to requirement 'std::is_const<int>()': message}}
 static_assert(!(std::is_const<const ExampleTypes::T>()()), "message");
-// expected-error@-1{{static_assert failed due to requirement '!(std::is_const<const int>()())': message}}
+// expected-error@-1{{static assertion failed due to requirement '!(std::is_const<const int>()())': message}}
 static_assert(std::is_same<decltype(std::is_const<const ExampleTypes::T>()), int>::value, "message");
-// expected-error@-1{{static_assert failed due to requirement 'std::is_same<std::is_const<const int>, int>::value': message}}
+// expected-error@-1{{static assertion failed due to requirement 'std::is_same<std::is_const<const int>, int>::value': message}}
 static_assert(std::is_const<decltype(ExampleTypes::T(3))>::value, "message");
-// expected-error@-1{{static_assert failed due to requirement 'std::is_const<int>::value': message}}
+// expected-error@-1{{static assertion failed due to requirement 'std::is_const<int>::value': message}}
 static_assert(std::is_const<decltype(ExampleTypes::T())>::value, "message");
-// expected-error@-1{{static_assert failed due to requirement 'std::is_const<int>::value': message}}
+// expected-error@-1{{static assertion failed due to requirement 'std::is_const<int>::value': message}}
 static_assert(std::is_const<decltype(ExampleTypes(3))>::value, "message");
-// expected-error@-1{{static_assert failed due to requirement 'std::is_const<ExampleTypes>::value': message}}
+// expected-error@-1{{static assertion failed due to requirement 'std::is_const<ExampleTypes>::value': message}}
 
 struct BI_tag {};
 struct RAI_tag : BI_tag {};
@@ -160,7 +160,7 @@
 template <class Container>
 void foo() {
   static_assert(std::is_same<RAI_tag, typename Container::iterator::tag>::value, "message");
-  // expected-error@-1{{static_assert failed due to requirement 'std::is_same<RAI_tag, BI_tag>::value': message}}
+  // expected-error@-1{{static assertion failed due to requirement 'std::is_same<RAI_tag, BI_tag>::value': message}}
 }
 template void foo<MyContainer>();
 // expected-note@-1{{in instantiation of function template specialization 'foo<MyContainer>' requested here}}
@@ -178,7 +178,7 @@
 template <typename T, typename U, int a>
 void foo2() {
   static_assert(::ns::NestedTemplates1<T, a>::NestedTemplates2::template NestedTemplates3<U>::value, "message");
-  // expected-error@-1{{static_assert failed due to requirement '::ns::NestedTemplates1<int, 3>::NestedTemplates2::NestedTemplates3<float>::value': message}}
+  // expected-error@-1{{static assertion failed due to requirement '::ns::NestedTemplates1<int, 3>::NestedTemplates2::NestedTemplates3<float>::value': message}}
 }
 template void foo2<int, float, 3>();
 // expected-note@-1{{in instantiation of function template specialization 'foo2<int, float, 3>' requested here}}
@@ -186,9 +186,9 @@
 template <class T>
 void foo3(T t) {
   static_assert(std::is_const<T>::value, "message");
-  // expected-error-re@-1{{static_assert failed due to requirement 'std::is_const<(lambda at {{.*}}static-assert.cpp:{{[0-9]*}}:{{[0-9]*}})>::value': message}}
+  // expected-error-re@-1{{static assertion failed due to requirement 'std::is_const<(lambda at {{.*}}static-assert.cpp:{{[0-9]*}}:{{[0-9]*}})>::value': message}}
   static_assert(std::is_const<decltype(t)>::value, "message");
-  // expected-error-re@-1{{static_assert failed due to requirement 'std::is_const<(lambda at {{.*}}static-assert.cpp:{{[0-9]*}}:{{[0-9]*}})>::value': message}}
+  // expected-error-re@-1{{static assertion failed due to requirement 'std::is_const<(lambda at {{.*}}static-assert.cpp:{{[0-9]*}}:{{[0-9]*}})>::value': message}}
 }
 void callFoo3() {
   foo3([]() {});
@@ -206,7 +206,7 @@
 static_assert(42, "message");
 static_assert(42.0, "message"); // expected-warning {{implicit conversion from 'double' to 'bool' changes value from 42 to true}}
 constexpr int *p = 0;
-static_assert(p, "message"); // expected-error {{static_assert failed}}
+static_assert(p, "message"); // expected-error {{static assertion failed}}
 
 struct NotBool {
 } notBool;
diff --git a/clang/test/SemaCXX/using-decl-templates.cpp b/clang/test/SemaCXX/using-decl-templates.cpp
--- a/clang/test/SemaCXX/using-decl-templates.cpp
+++ b/clang/test/SemaCXX/using-decl-templates.cpp
@@ -95,7 +95,7 @@
 
 namespace DontDiagnoseInvalidTest {
 template <bool Value> struct Base {
-  static_assert(Value, ""); // expected-error {{static_assert failed}}
+  static_assert(Value, ""); // expected-error {{static assertion failed}}
 };
 struct Derived : Base<false> { // expected-note {{requested here}}
   using Base<false>::Base; // OK. Don't diagnose that 'Base' isn't a base class of Derived.
diff --git a/clang/test/SemaCXX/weak-init.cpp b/clang/test/SemaCXX/weak-init.cpp
--- a/clang/test/SemaCXX/weak-init.cpp
+++ b/clang/test/SemaCXX/weak-init.cpp
@@ -2,7 +2,7 @@
 
 extern const int W1 __attribute__((weak)) = 10; // expected-note {{declared here}}
 
-static_assert(W1 == 10, ""); // expected-error   {{static_assert expression is not an integral constant expression}}
+static_assert(W1 == 10, ""); // expected-error   {{static assertion expression is not an integral constant expression}}
                              // expected-note@-1 {{initializer of weak variable 'W1' is not considered constant because it may be different at runtime}}
 
 extern const int W2 __attribute__((weak)) = 20;
diff --git a/clang/test/SemaTemplate/instantiate-var-template.cpp b/clang/test/SemaTemplate/instantiate-var-template.cpp
--- a/clang/test/SemaTemplate/instantiate-var-template.cpp
+++ b/clang/test/SemaTemplate/instantiate-var-template.cpp
@@ -31,7 +31,7 @@
   static_assert(b<char> == 1, ""); // expected-note {{in instantiation of}} expected-error {{not an integral constant}}
 
   template<typename T> void f() {
-    static_assert(a<sizeof(sizeof(f(T())))> == 0, ""); // expected-error {{static_assert failed due to requirement 'a<sizeof (sizeof (f(type-parameter-0-0())))> == 0'}}
+    static_assert(a<sizeof(sizeof(f(T())))> == 0, ""); // expected-error {{static assertion failed due to requirement 'a<sizeof (sizeof (f(type-parameter-0-0())))> == 0'}}
   }
 }
 
diff --git a/clang/test/SemaTemplate/pr52909.cpp b/clang/test/SemaTemplate/pr52909.cpp
--- a/clang/test/SemaTemplate/pr52909.cpp
+++ b/clang/test/SemaTemplate/pr52909.cpp
@@ -15,7 +15,7 @@
   // expected-note@-1 {{because 't.begin' would be invalid: reference to non-static member function must be called}}
 };
 
-static_assert(Beginable<A>); // expected-error {{static_assert failed}}
+static_assert(Beginable<A>); // expected-error {{static assertion failed}}
                              // expected-note@-1 {{does not satisfy 'Beginable'}}
 } // namespace PR52905
 
@@ -48,7 +48,7 @@
     static void begin(double);
 };
 
-static_assert(C<A>); // expected-error {{static_assert failed}}
+static_assert(C<A>); // expected-error {{static assertion failed}}
   // expected-note@-1 {{because 'PR52909b::A' does not satisfy 'C'}}
 
 } // namespace PR52909b
@@ -65,7 +65,7 @@
     int *f() const;
 };
 
-static_assert(C<S>); // expected-error {{static_assert failed}}
+static_assert(C<S>); // expected-error {{static assertion failed}}
   // expected-note@-1 {{because 'PR53075::S' does not satisfy 'C'}}
 
 } // namespace PR53075
diff --git a/clang/test/SemaTemplate/pr52970.cpp b/clang/test/SemaTemplate/pr52970.cpp
--- a/clang/test/SemaTemplate/pr52970.cpp
+++ b/clang/test/SemaTemplate/pr52970.cpp
@@ -32,7 +32,7 @@
 
 static_assert(C<Good>);
 static_assert(!C<Bad>);
-static_assert(C<Bad>); // cxx20-error {{static_assert failed}}
+static_assert(C<Bad>); // cxx20-error {{static assertion failed}}
   // cxx20-note@-1 {{because 'DotFollowingFunctionName::Bad' does not satisfy 'C'}}
 #endif
 } // namespace DotFollowingFunctionName
@@ -57,7 +57,7 @@
 
 static_assert(C<Good>);
 static_assert(!C<Bad>);
-static_assert(C<Bad>); // cxx20-error {{static_assert failed}}
+static_assert(C<Bad>); // cxx20-error {{static assertion failed}}
   // cxx20-note@-1 {{because 'DotFollowingPointer::Bad' (aka 'Holder<Incomplete> *') does not satisfy 'C'}}
 #endif
 } // namespace DotFollowingPointer
diff --git a/clang/test/SemaTemplate/temp_arg_nontype_cxx20.cpp b/clang/test/SemaTemplate/temp_arg_nontype_cxx20.cpp
--- a/clang/test/SemaTemplate/temp_arg_nontype_cxx20.cpp
+++ b/clang/test/SemaTemplate/temp_arg_nontype_cxx20.cpp
@@ -184,7 +184,7 @@
 
 namespace Diags {
   struct A { int n, m; };
-  template<A a> struct X { static_assert(a.n == a.m); }; // expected-error {{static_assert failed due to requirement 'Diags::A{1, 2}.n == Diags::A{1, 2}.m'}}
+  template<A a> struct X { static_assert(a.n == a.m); }; // expected-error {{static assertion failed due to requirement 'Diags::A{1, 2}.n == Diags::A{1, 2}.m'}}
   template struct X<A{1, 2}>; // expected-note {{in instantiation of template class 'Diags::X<{1, 2}>' requested here}}
 }