loplugin:redundantcast check for c-style casts to void

Change-Id: Ic8b99f590436f94825e471bc61411c69fd768862
Reviewed-on: https://gerrit.libreoffice.org/36208Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

compilerplugins/clang/redundantcast.cxx

@@ -307,7 +307,8 @@ bool RedundantCast::VisitCStyleCastExpr(CStyleCastExpr const * expr) {
         return true;
     }
     bool bBuiltinType = t1->isSpecificBuiltinType(BuiltinType::Bool) || t1->isSpecificBuiltinType(BuiltinType::Double)
-                        || t1->isSpecificBuiltinType(BuiltinType::Float);
+                        || t1->isSpecificBuiltinType(BuiltinType::Float)
+                        || t1->isSpecificBuiltinType(BuiltinType::Void);
     if ((bBuiltinType || loplugin::TypeCheck(t1).Typedef()) && t1 == t2)
     {
         // Ignore FD_ISSET expanding to "...(SOCKET)(fd)..." in some Microsoft

idlc/source/aststack.cxx

@@ -64,7 +64,7 @@ AstScope* AstStack::nextToTop()
         return nullptr;
 
     tmp = top();        // Save top
-    (void) pop();       // Pop it
+    pop();              // Pop it
     retval = top();     // Get next one down
     (void) push(tmp);   // Push top back
     return retval;      // Return next one down

sc/source/core/data/table4.cxx

@@ -410,7 +410,7 @@ void ScTable::FillAnalyse( SCCOL nCol1, SCROW nRow1, SCCOL nCol2, SCROW nRow2,
             nRow = sal::static_int_cast<SCROW>( nRow + nAddY );
             for (SCSIZE i=1; i<nCount && rListData; i++)
             {
-                (void)GetString(nCol, nRow, aStr);
+                GetString(nCol, nRow, aStr);
                 if (!rListData->GetSubIndex(aStr, rListIndex, bMatchCase))
                     rListData = nullptr;
                 nCol = sal::static_int_cast<SCCOL>( nCol + nAddX );

starmath/qa/cppunit/test_node.cxx

@@ -71,10 +71,10 @@ void NodeTest::testTdf47813()
 #undef MATRIX
     ScopedVclPtrInstance<VirtualDevice> pOutputDevice;
     SmFormat aFmt;
-    (void)pNodeA->Arrange(*pOutputDevice, aFmt);
-    (void)pNodeC->Arrange(*pOutputDevice, aFmt);
-    (void)pNodeL->Arrange(*pOutputDevice, aFmt);
-    (void)pNodeR->Arrange(*pOutputDevice, aFmt);
+    pNodeA->Arrange(*pOutputDevice, aFmt);
+    pNodeC->Arrange(*pOutputDevice, aFmt);
+    pNodeL->Arrange(*pOutputDevice, aFmt);
+    pNodeR->Arrange(*pOutputDevice, aFmt);
     long nWidthA = pNodeA->GetRect().GetWidth();
     long nWidthC = pNodeC->GetRect().GetWidth();
     long nWidthL = pNodeL->GetRect().GetWidth();