Split -Wunused-variable warning.

With r190382, -Wunused-variable warns about unused const variables when
appropriate. For codebases that use -Werror, this poses a problem as
existing unused const variables need to be cleaned up first. To make the
transistion easier, this patch splits -Wunused-variable by pulling out
an additional -Wunused-const-variable (by default activated along with
-Wunused-variable).

llvm-svn: 190508

1 files changed, 3 insertions, 0 deletions

diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index 91f6d5f7c21..c6f213a7380 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -758,6 +758,9 @@ void Sema::ActOnEndOfTranslationUnit() {
         if (DiagD->isReferenced()) {
           Diag(DiagD->getLocation(), diag::warn_unneeded_internal_decl)
                 << /*variable*/1 << DiagD->getDeclName();
+        } else if (DiagD->getType().isConstQualified()) {
+          Diag(DiagD->getLocation(), diag::warn_unused_const_variable)
+              << DiagD->getDeclName();
         } else {
           Diag(DiagD->getLocation(), diag::warn_unused_variable)
               << DiagD->getDeclName();