update

Author: cezarbbb

tests/ui/README.md

@@ -1312,6 +1312,10 @@ Tests on static items.
 
 **FIXME**: should probably be merged with `tests/ui/static/`.
 
+## `tests/ui/staticlib-hide-internal-symbols/`: `-Zstaticlib-hide-internal-symbols` command line flag
+
+Tests for the `-Zstaticlib-hide-internal-symbols` flag, which hides non-exported symbols in ELF static libraries.
+
 ## `tests/ui/stats/`
 
 Tests for compiler-internal stats; `-Z meta-stats` and `-Z input-stats` flags.