https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98646
Bug ID: 98646
Summary: A static_cast confuses -Wnonnull, causing false
positives
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: ville.voutilainen at gmail dot com
Target Milestone: ---
Created attachment 49957
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=49957&action=edit
Preprocessed source
Compile with
/usr/local/bin/c++ -DQT_ASCII_CAST_WARNINGS -DQT_BUILDING_QT
-DQT_BUILD_XCB_PLUGIN -DQT_BUILD_XCB_QPA_LIB_LIB -DQT_CORE_LIB
-DQT_DEPRECATED_WARNINGS -DQT_DEPRECATED_WARNINGS_SINCE=0x060000
-DQT_DISABLE_DEPRECATED_BEFORE=0x050000 -DQT_GUI_LIB -DQT_MOC_COMPAT
-DQT_NO_CAST_TO_ASCII -DQT_NO_EXCEPTIONS -DQT_NO_FOREACH -DQT_OPENGL_LIB
-DQT_USE_QSTRINGBUILDER -DXcbQpa_EXPORTS -D_LARGEFILE64_SOURCE
-D_LARGEFILE_SOURCE -fPIC -fvisibility=hidden -fvisibility-inlines-hidden -Wall
-Wextra -fno-exceptions -fPIC -Werror -Wno-error=cpp
-Wno-error=deprecated-declarations -Wno-error=strict-overflow
-Wno-error=implicit-fallthrough -Wno-error=deprecated-copy
-Wno-error=redundant-move -Wno-error=init-list-lifetime
-Wno-error=format-overflow -Wsuggest-override -std=c++17 -c winid-nonnull.cpp
The result is
/home/vivoutil/kuutti/kuuttikutonen/qt5/qtbase/src/plugins/platforms/xcb/qxcbwindow.cpp:
In member function ‘void QXcbWindow::show()’:
/home/vivoutil/kuutti/kuuttikutonen/qt5/qtbase/src/plugins/platforms/xcb/qxcbwindow.cpp:685:91:
error: ‘this’ pointer null [-Werror=nonnull]
685 | transientXcbParent = static_cast<const QXcbWindow
*>(tp->handle())->winId();
|
^
In file included from
/home/vivoutil/kuutti/kuuttikutonen/qt5/qtbase/src/plugins/platforms/xcb/qxcbwindow.cpp:40:
/home/vivoutil/kuutti/kuuttikutonen/qt5/qtbase/src/plugins/platforms/xcb/qxcbwindow.h:87:9:
note: in a call to non-static member function ‘virtual WId QXcbWindow::winId()
const’
87 | WId winId() const override;
| ^~~~~
Removing the static_cast removes the warning.
