[PATCH] scripts/tags.sh: Prevent binary files appearing in cscope.files

PROBLEM

When executing the command `make COMPILED_SOURCE=1 cscope`, the resulting
`cscope.files` file contains filenames with the extensions *.rlib, *.rmeta,
and *.so.

SOLUTION

Modify the regular expression in the `all_compiled_sources()` function so
that only files with the extensions *.h, *.c, *.S, and *.rs are accepted.

---

This is the first part of this patch:
https://lore.kernel.org/lkml/[email protected]/

which I have split into two parts, as suggested by Nicolas Schier here:
https://lore.kernel.org/lkml/akVkIrcpNxZrrfii@levanger/

Signed-off-by: Sergei Litvin <[email protected]>
---
 scripts/tags.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/tags.sh b/scripts/tags.sh
index 243373683f98..c9dc2763a505 100755
--- a/scripts/tags.sh
+++ b/scripts/tags.sh
@@ -100,7 +100,7 @@ all_compiled_sources()
 	{
 		echo include/generated/autoconf.h
 		find $ignore -name "*.cmd" -exec \
-			grep -Poh '(?<=^  )\S+|(?<== )\S+[^\\](?=$)' {} \+ |
+			grep -Poh '(?<=^  )\S+\.([chS]|rs)(?=\s)|(?<== )\S+\.(?1)(?=$)' {} \+ |
 		awk '!a[$0]++'
 	} | xargs realpath -esq $([ -z "$KBUILD_ABS_SRCTREE" ] && echo --relative-to=.) |
 	sort -u
-- 
2.54.0