[clang] Extend -Wnonportable-include-path with a warning about trailing whitespace or dots (PR #96960)

[via cfe-commits]

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@@ -0,0 +1,11 @@
+// REQUIRES: case-insensitive-filesystem
+// RUN: %clang_cc1 -Wall %s
+
+#include "empty_file_to_include.h " // expected-warning {{non-portable path}}
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zmodem wrote:

The expected-warning directives require running clang with the `-verify` flag.

https://github.com/llvm/llvm-project/pull/96960