[index] Index static_assert declarations

static_assert declarations have to be visited while indexing so that we can
gather the references to declarations that are present in their assert
expression.

Differential Revision: https://reviews.llvm.org/D33913

llvm-svn: 305504
diff --git a/clang/lib/Index/IndexDecl.cpp b/clang/lib/Index/IndexDecl.cpp
index 870b4e4..c4e9a1a 100644
--- a/clang/lib/Index/IndexDecl.cpp
+++ b/clang/lib/Index/IndexDecl.cpp
@@ -682,6 +682,13 @@
   bool VisitImportDecl(const ImportDecl *D) {
     return IndexCtx.importedModule(D);
   }
+
+  bool VisitStaticAssertDecl(const StaticAssertDecl *D) {
+    IndexCtx.indexBody(D->getAssertExpr(),
+                       dyn_cast<NamedDecl>(D->getDeclContext()),
+                       D->getLexicalDeclContext());
+    return true;
+  }
 };
 
 } // anonymous namespace