Revert r168519, "Merge used flags so that we don't have to iterate on isUsed. With this change"

It brought bunch of (possibly false) warnings.

llvm/unittests/VMCore/PassManagerTest.cpp:60:22: warning: variable 'ID' is not needed and will not be emitted [-Wunneeded-internal-declaration]
    char ModuleNDNM::ID=0;
                     ^
llvm/unittests/VMCore/PassManagerTest.cpp:86:22: warning: variable 'ID' is not needed and will not be emitted [-Wunneeded-internal-declaration]
    char ModuleNDM2::ID=0;
                     ^
llvm/unittests/VMCore/PassManagerTest.cpp:106:21: warning: variable 'ID' is not needed and will not be emitted [-Wunneeded-internal-declaration]
    char ModuleDNM::ID=0;
                    ^
llvm/unittests/VMCore/PassManagerTest.cpp:217:16: warning: variable 'initcount' is not needed and will not be emitted [-Wunneeded-internal-declaration]
    int LPass::initcount=0;
               ^
llvm/unittests/VMCore/PassManagerTest.cpp:218:16: warning: variable 'fincount' is not needed and will not be emitted [-Wunneeded-internal-declaration]
    int LPass::fincount=0;
               ^
llvm/unittests/VMCore/PassManagerTest.cpp:259:16: warning: variable 'inited' is not needed and will not be emitted [-Wunneeded-internal-declaration]
    int BPass::inited=0;
               ^
llvm/unittests/VMCore/PassManagerTest.cpp:260:16: warning: variable 'fin' is not needed and will not be emitted [-Wunneeded-internal-declaration]
    int BPass::fin=0;
               ^
llvm/unittests/VMCore/PassManagerTest.cpp:283:24: warning: variable 'ID' is not needed and will not be emitted [-Wunneeded-internal-declaration]
    char OnTheFlyTest::ID=0;
                       ^
8 warnings generated.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@168549 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 7 insertions, 0 deletions

diff --git a/lib/AST/DeclBase.cpp b/lib/AST/DeclBase.cpp
index b04c149dee..7b20e7751a 100644
--- a/lib/AST/DeclBase.cpp
+++ b/lib/AST/DeclBase.cpp
@@ -261,6 +261,13 @@ bool Decl::isUsed(bool CheckUsedAttr) const {
   if (CheckUsedAttr && hasAttr<UsedAttr>())
     return true;
 
+  // Check redeclarations. We merge attributes, so we don't need to check
+  // attributes in all redeclarations.
+  for (redecl_iterator I = redecls_begin(), E = redecls_end(); I != E; ++I) {
+    if (I->Used)
+      return true;
+  }
+
   return false; 
 }