Remove obsolete "lo_warn_unused" workaround

Per README.md, Clang 3.4 is the baseline for --enable-compiler-plugins, which is
the sole consumer of the "lo_warn_unused" attribute, but Clang 3.4 already
supports HAVE_GCC_ATTRIBUTE_WARN_UNUSED.

Change-Id: I9654028e24852335e463c73bcb5ece5e5b54d53c

1 files changed, 0 insertions, 12 deletions

diff --git a/compilerplugins/clang/check.cxx b/compilerplugins/clang/check.cxx
index 8a468e48eba4..03d9683a4903 100644
--- a/compilerplugins/clang/check.cxx
+++ b/compilerplugins/clang/check.cxx
@@ -214,18 +214,6 @@ bool isExtraWarnUnusedType(clang::QualType type) {
     if (rec == nullptr) {
         return false;
     }
-    if (rec->hasAttrs()) {
-        // Clang currently has no support for custom attributes, but the
-        // annotate attribute comes close, so check for
-        // __attribute__((annotate("lo_warn_unused"))):
-        for (auto i = rec->specific_attr_begin<clang::AnnotateAttr>(),
-                 e = rec->specific_attr_end<clang::AnnotateAttr>();
-             i != e; ++i) {
-            if ((*i)->getAnnotation() == "lo_warn_unused") {
-                return true;
-            }
-        }
-    }
     auto const tc = TypeCheck(rec);
     // Check some common non-LO types:
     if (tc.Class("string").Namespace("std").GlobalNamespace()