loplugin:redundantcast: cstyle_cast within reinterpret_cast

Change-Id: Ie31c9dd6d8741aa856553b798bb5b7f695a3fe0f
Reviewed-on: https://gerrit.libreoffice.org/42776
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>
Tested-by: Stephan Bergmann <sbergman@redhat.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/compilerplugins/clang/redundantcast.cxx b/compilerplugins/clang/redundantcast.cxx
index dba573387743..30914a460dc4 100644
--- a/compilerplugins/clang/redundantcast.cxx
+++ b/compilerplugins/clang/redundantcast.cxx
@@ -522,6 +522,20 @@ bool RedundantCast::VisitCXXReinterpretCastExpr(
             expr->getExprLoc())
             << expr->getSubExprAsWritten()->getType() << expr->getType()
             << expr->getSourceRange();
+    } else if (expr->getType()->isFundamentalType()) {
+        if (auto const sub = dyn_cast<CXXConstCastExpr>(
+                expr->getSubExpr()->IgnoreParens()))
+        {
+            report(
+                DiagnosticsEngine::Warning,
+                ("redundant const_cast from %0 to %1 within reinterpret_cast to"
+                 " fundamental type %2"),
+                expr->getExprLoc())
+                << sub->getSubExprAsWritten()->getType()
+                << sub->getTypeAsWritten() << expr->getTypeAsWritten()
+                << expr->getSourceRange();
+            return true;
+        }
     }
     return true;
 }