Make loplugin:redundantcast accept bool(FD_ISSET(...)) again

Change-Id: I4e96c55c246cf806f17df31844a00d0e8a5e4f56

compilerplugins/clang/redundantcast.cxx

@@ -483,6 +483,30 @@ bool RedundantCast::VisitCXXFunctionalCastExpr(CXXFunctionalCastExpr const * exp
     if (loplugin::hasPathnamePrefix(aFileName, SRCDIR "/svx/source/tbxctrls/fillctrl.cxx"))
         return true;
 
+    // See the commit message of d0e7d020fa405ab94f19916ec96fbd4611da0031
+    // "socket.c -> socket.cxx" for the reason to have
+    //
+    //   bool(FD_ISSET(...))
+    //
+    // in sal/osl/unx/socket.cxx:
+    auto const sub = compat::getSubExprAsWritten(expr);
+    //TODO: Better check that sub is exactly an expansion of FD_ISSET:
+    if (sub->getLocEnd().isMacroID()) {
+        for (auto loc = sub->getLocStart();
+             loc.isMacroID()
+                 && (compiler.getSourceManager()
+                     .isAtStartOfImmediateMacroExpansion(loc));
+             loc = compiler.getSourceManager().getImmediateMacroCallerLoc(loc))
+        {
+            if (Lexer::getImmediateMacroName(
+                    loc, compiler.getSourceManager(), compiler.getLangOpts())
+                == "FD_ISSET")
+            {
+                return true;
+            }
+        }
+    }
+
     auto const t1 = expr->getTypeAsWritten();
     auto const t2 = compat::getSubExprAsWritten(expr)->getType();
     if (t1 != t2)

sal/osl/unx/socket.cxx

@@ -2399,7 +2399,7 @@ sal_Bool SAL_CALL osl_isInSocketSet(oslSocketSet Set, oslSocket pSocket)
         return false;
     }
 
-    return FD_ISSET(pSocket->m_Socket, &Set->m_Set);
+    return bool(FD_ISSET(pSocket->m_Socket, &Set->m_Set));
 }
 
 sal_Int32 SAL_CALL osl_demultiplexSocketEvents(oslSocketSet IncomingSet,