improve unnecessarycatchthrow plugin

it is not legal to eliminate a catch/re-throw where the re-throw
expliciting mentions the exception variable and the exception variable
is a non-final class

Change-Id: I7fd88b0d004d2efa66aef2c0876e07f203da3c28
Reviewed-on: https://gerrit.libreoffice.org/42782
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
Tested-by: Noel Grandin <noel.grandin@collabora.co.uk>

1 files changed, 9 insertions, 0 deletions

diff --git a/compilerplugins/clang/unnecessarycatchthrow.cxx b/compilerplugins/clang/unnecessarycatchthrow.cxx
index c69713799a82..948394e9e37a 100644
--- a/compilerplugins/clang/unnecessarycatchthrow.cxx
+++ b/compilerplugins/clang/unnecessarycatchthrow.cxx
@@ -58,6 +58,15 @@ bool UnnecessaryCatchThrow::VisitCXXTryStmt(CXXTryStmt const * tryStmt)
     auto subExpr = throwExpr->getSubExpr();
     if (subExpr)
     {
+        if (auto cxxConstructExpr = dyn_cast<CXXConstructExpr>(subExpr)) {
+            if (!cxxConstructExpr->getConstructor()->isCopyConstructor())
+                return true;
+            if (!cxxConstructExpr->getConstructor()->getParent()->hasAttr<FinalAttr>())
+                return true;
+            if (cxxConstructExpr->getNumArgs() != 1)
+                return true;
+            subExpr = cxxConstructExpr->getArg(0);
+        }
         auto declRefExpr = dyn_cast<DeclRefExpr>(subExpr->IgnoreImpCasts());
         if (!declRefExpr)
             return true;