[PATCH v2] scripts: generate_rust_analyzer: Add message to sysroot assertion

[Maurice Hieronymus <mhi@mailbox.org>]

The assertion that checks whether sysroot lies within sysroot_src
currently fails without explaining why. Add an error message that
prints both paths to make diagnosing toolchain issues easier.

Signed-off-by: Maurice Hieronymus <mhi@mailbox.org>
---
Changes since v2:
- Rebase to current rust/for-next
- Send patch to all people received from scripts/get_maintainer.pl

 scripts/generate_rust_analyzer.py | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/scripts/generate_rust_analyzer.py b/scripts/generate_rust_analyzer.py
index d2bc63cde8c6..06c220c9ceee 100755
--- a/scripts/generate_rust_analyzer.py
+++ b/scripts/generate_rust_analyzer.py
@@ -156,7 +156,13 @@ def main():
     )
 
     # Making sure that the `sysroot` and `sysroot_src` belong to the same toolchain.
-    assert args.sysroot in args.sysroot_src.parents
+    assert args.sysroot in args.sysroot_src.parents, \
+        f"""
+        It seems like your sysroot and sysroot_src do not belong to the same toolchain.
+        The sysroot folder must be inside sysroot_src.
+        sysroot={args.sysroot}
+        sysroot_src={args.sysroot_src}
+        """
 
     rust_project = {
         "crates": generate_crates(args.srctree, args.objtree, args.sysroot_src, args.exttree, args.cfgs),

base-commit: 8af7a50167833b6b22e30c008bbf95ab3ff1a5fb
-- 
2.50.1