[clang] [Modules] Process include files changes with -fmodules-validate-input-files-content and -fno-pch-timestamp options (PR #90319)

[Ivan Murashko via cfe-commits]

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@@ -0,0 +1,34 @@
+// UNSUPPORTED: system-windows
+// RUN: rm -rf %t
+// RUN: split-file %s %t
+// RUN: cd %t
+//
+// RUN: cp a1.h a.h
+// RUN: %clang -fmodules -fmodules-validate-input-files-content -Xclang -fno-pch-timestamp -fimplicit-modules -fmodule-map-file=module.modulemap -fsyntax-only  -fmodules-cache-path=%t test1.cpp
+// RUN: cp a2.h a.h
+// RUN: %clang -fmodules -fmodules-validate-input-files-content -Xclang -fno-pch-timestamp -fimplicit-modules -fmodule-map-file=module.modulemap -fsyntax-only  -fmodules-cache-path=%t test2.cpp
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ivanmurashko wrote:

> Does this test need to use the clang driver for some reason

Unfortunately, yes. The option `-fmodules-validate-input-files-content` is a driver only option.

https://github.com/llvm/llvm-project/pull/90319