[NFC] Update test for clang/test/Modules/cxx20-force-check-input.cppm

The original test is stale. Update it.

Author: ChuanqiXu9

clang/test/Modules/cxx20-force-check-input.cppm

@@ -2,19 +2,18 @@
 // RUN: split-file %s %t
 //
 // RUN: %clang_cc1 -std=c++20 -triple %itanium_abi_triple \
+// RUN:     -fforce-check-cxx20-modules-input-files \
 // RUN:     %t/a.cppm -emit-module-interface -o %t/a.pcm
 //
 // RUN: echo "inline int bar = 46;" >> %t/foo.h
-// RUNX: %clang_cc1 -std=c++20 -triple %itanium_abi_triple \
-// RUNX:     %t/use.cpp -fmodule-file=a=%t/a.pcm -verify -fsyntax-only
-// RUNX: %clang_cc1 -std=c++20 -triple %itanium_abi_triple \
-// RUNX:     %t/a.pcm -emit-llvm -o - | FileCheck %t/a.ll
-//
+// RUN: not %clang_cc1 -std=c++20 -triple %itanium_abi_triple \
+// RUN:     -fforce-check-cxx20-modules-input-files %t/a.pcm \
+// RUN:     -emit-llvm -o -  2>&1 | FileCheck %t/a.cppm -check-prefix=CHECK-HEADER-FAILURE
+// RUN: %clang_cc1 -std=c++20 -triple %itanium_abi_triple \
+// RUN:     -fforce-check-cxx20-modules-input-files \
+// RUN:     %t/a.cppm -emit-module-interface -o %t/a.pcm
+
 // RUN: echo "export int var = 43;" >> %t/a.cppm
-// RUNX: %clang_cc1 -std=c++20 -triple %itanium_abi_triple \
-// RUNX:     %t/use.cpp -fmodule-file=a=%t/a.pcm -verify -fsyntax-only
-// RUNX: %clang_cc1 -std=c++20 -triple %itanium_abi_triple \
-// RUNX:     %t/a.pcm -emit-llvm -o - | FileCheck %t/a.ll
 //
 // RUN: not %clang_cc1 -std=c++20 -triple %itanium_abi_triple \
 // RUN:     -fforce-check-cxx20-modules-input-files %t/a.pcm \
@@ -30,4 +29,5 @@ module;
 export module a;
 export using ::foo;
 
+// CHECK-HEADER-FAILURE: fatal error:{{.*}}foo.h' has been modified since the AST file {{.*}}was built
 // CHECK-FAILURE: fatal error:{{.*}}a.cppm' has been modified since the AST file {{.*}}was built