[clang] [Multilib] Extend the Multilib system to support an IncludepPath field. (PR #146651)

[Simon Tatham via cfe-commits]

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+
+# REQUIRES: shell
+# UNSUPPORTED: system-windows
+
+# This test demonstrates the new "IncludePath" field.
+# This field allows specifying include paths through
+# multilib.yaml configuration using relative paths.
+# Absolute paths should be rejected by the driver
+# with an appropriate diagnostic message.
+#
+# This test verifies that passing an absolute path
+# (/include) to IncludePath triggers the expected
+# error.
+
+# # RUN: %clang --target=aarch64-none-elf --multi-lib-config=%s %s -### -o /dev/null 2>&1 \
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statham-arm wrote:

Ah, I see! Well found.

https://github.com/llvm/llvm-project/pull/146651