New AST-only detector that flags call sites whose target decl is
marked deprecated under any of the three idioms:
- `[[deprecated]]` / `[[deprecated("why")]]` (C++14 attribute)
- `__attribute__((deprecated))` (GCC/Clang extension)
- `__attribute__((availability(...,deprecated=N.M)))` (Apple)
Per-call rather than per-decl so a migration that updates call
sites one at a time shows monotone progress. Deprecation reason
(when present) carries through into finding.message. System-header
call sites are skipped so the report stays scoped to the user's
own code.
Curl baseline: 52 real findings, e.g.
ldap.c:269 ldap_url_parse — first deprecated in macOS 10.11
multi-formadd.c:50 curl_formadd — since 7.56.0. Use curl_mime_init()
Refs docs/library-expansion-matrix.md row C7.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
