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

[Aaron Ballman 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}}
+#include "empty_file_to_include.h." // expected-warning {{non-portable path}}
+#include "empty_file_to_include.h       " // expected-warning {{non-portable path}}
+#include "empty_file_to_include.h......." // expected-warning {{non-portable path}}
+#include "empty_file_to_include.h . . . " // expected-warning {{non-portable path}}
+#include "empty_file_to_include.h.. .. " // expected-warning {{non-portable path}}
+
+#include "empty_file_to_include.h" // No warning
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AaronBallman wrote:

Please add a newline to the end of the file.

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