GUI: Could not load widget position for ''!

[angstsmurf]

It seems I can crash ScummVM 1.9.0 by starting it in graphics mode Normal (no scaling), changing graphics mode to OpenGL in options, switching to the Paths panel and then clicking on OK. The console will show the error Could not load widget position for ''!

ScummVM 1.9.0 stable, OS X 64-bit version, OS X El Capitan 10.11.6

[criezy]

I can reproduce it with the current master, although it sometimes crashes just before arriving to this error in the _name.empty() test. The first two errors given by valgrind are:

==87107== Invalid read of size 8
==87107==    at 0x1020DDF1F: GUI::TabWidget::reflowLayout() (tab.cpp:280)
==87107==    by 0x10206A038: GUI::Dialog::reflowLayout() (dialog.cpp:120)
==87107==    by 0x10208DB1D: GUI::OptionsDialog::reflowLayout() (options.cpp:1124)
==87107==    by 0x102094CA2: GUI::GlobalOptionsDialog::reflowLayout() (options.cpp:1862)
==87107==    by 0x102079AB0: GUI::GuiManager::screenChange() (gui-manager.cpp:496)
==87107==    by 0x10207938F: GUI::GuiManager::checkScreenChange() (gui-manager.cpp:480)
==87107==    by 0x102086E17: GUI::OptionsDialog::close() (options.cpp:430)
==87107==    by 0x102092F81: GUI::GlobalOptionsDialog::close() (options.cpp:1576)
==87107==    by 0x102088B09: GUI::OptionsDialog::handleCommand(GUI::CommandSender*, unsigned int, unsigned int) (options.cpp:637)
==87107==    by 0x102094529: GUI::GlobalOptionsDialog::handleCommand(GUI::CommandSender*, unsigned int, unsigned int) (options.cpp:1809)
==87107==    by 0x10214C2EA: GUI::CommandSender::sendCommand(unsigned int, unsigned int) (object.h:55)
==87107==    by 0x1020CD2E9: GUI::ButtonWidget::handleMouseUp(int, int, int, int) (widget.cpp:339)
==87107==  Address 0x1058b4870 is 0 bytes inside a block of size 232 free'd
==87107==    at 0x4D8D: free (vg_replace_malloc.c:477)
==87107==    by 0x1020D1291: GUI::ButtonWidget::~ButtonWidget() (widget.h:197)
==87107==    by 0x102094C02: GUI::GlobalOptionsDialog::reflowLayout() (options.cpp:1857)
==87107==    by 0x102079AB0: GUI::GuiManager::screenChange() (gui-manager.cpp:496)
==87107==    by 0x10207938F: GUI::GuiManager::checkScreenChange() (gui-manager.cpp:480)
==87107==    by 0x102086E17: GUI::OptionsDialog::close() (options.cpp:430)
==87107==    by 0x102092F81: GUI::GlobalOptionsDialog::close() (options.cpp:1576)
==87107==    by 0x102088B09: GUI::OptionsDialog::handleCommand(GUI::CommandSender*, unsigned int, unsigned int) (options.cpp:637)
==87107==    by 0x102094529: GUI::GlobalOptionsDialog::handleCommand(GUI::CommandSender*, unsigned int, unsigned int) (options.cpp:1809)
==87107==    by 0x10214C2EA: GUI::CommandSender::sendCommand(unsigned int, unsigned int) (object.h:55)
==87107==    by 0x1020CD2E9: GUI::ButtonWidget::handleMouseUp(int, int, int, int) (widget.cpp:339)
==87107==    by 0x10206A4AE: GUI::Dialog::handleMouseUp(int, int, int, int) (dialog.cpp:212)
==87107== 
==87107== Invalid read of size 4
==87107==    at 0x10000409C: Common::String::empty() const (str.h:199)
==87107==    by 0x102083FB4: GUI::GuiObject::reflowLayout() (object.cpp:43)
==87107==    by 0x1020DDF27: GUI::TabWidget::reflowLayout() (tab.cpp:280)
==87107==    by 0x10206A038: GUI::Dialog::reflowLayout() (dialog.cpp:120)
==87107==    by 0x10208DB1D: GUI::OptionsDialog::reflowLayout() (options.cpp:1124)
==87107==    by 0x102094CA2: GUI::GlobalOptionsDialog::reflowLayout() (options.cpp:1862)
==87107==    by 0x102079AB0: GUI::GuiManager::screenChange() (gui-manager.cpp:496)
==87107==    by 0x10207938F: GUI::GuiManager::checkScreenChange() (gui-manager.cpp:480)
==87107==    by 0x102086E17: GUI::OptionsDialog::close() (options.cpp:430)
==87107==    by 0x102092F81: GUI::GlobalOptionsDialog::close() (options.cpp:1576)
==87107==    by 0x102088B09: GUI::OptionsDialog::handleCommand(GUI::CommandSender*, unsigned int, unsigned int) (options.cpp:637)
==87107==    by 0x102094529: GUI::GlobalOptionsDialog::handleCommand(GUI::CommandSender*, unsigned int, unsigned int) (options.cpp:1809)
==87107==  Address 0x1058b4888 is 24 bytes inside a block of size 232 free'd
==87107==    at 0x4D8D: free (vg_replace_malloc.c:477)
==87107==    by 0x1020D1291: GUI::ButtonWidget::~ButtonWidget() (widget.h:197)
==87107==    by 0x102094C02: GUI::GlobalOptionsDialog::reflowLayout() (options.cpp:1857)
==87107==    by 0x102079AB0: GUI::GuiManager::screenChange() (gui-manager.cpp:496)
==87107==    by 0x10207938F: GUI::GuiManager::checkScreenChange() (gui-manager.cpp:480)
==87107==    by 0x102086E17: GUI::OptionsDialog::close() (options.cpp:430)
==87107==    by 0x102092F81: GUI::GlobalOptionsDialog::close() (options.cpp:1576)
==87107==    by 0x102088B09: GUI::OptionsDialog::handleCommand(GUI::CommandSender*, unsigned int, unsigned int) (options.cpp:637)
==87107==    by 0x102094529: GUI::GlobalOptionsDialog::handleCommand(GUI::CommandSender*, unsigned int, unsigned int) (options.cpp:1809)
==87107==    by 0x10214C2EA: GUI::CommandSender::sendCommand(unsigned int, unsigned int) (object.h:55)
==87107==    by 0x1020CD2E9: GUI::ButtonWidget::handleMouseUp(int, int, int, int) (widget.cpp:339)
==87107==    by 0x10206A4AE: GUI::Dialog::handleMouseUp(int, int, int, int) (dialog.cpp:212)
==87107== 

I will also attach the full valgrind output.

[criezy]

Valgrind output

[criezy]

Thank you for reporting this bug.
It was due to a logical error in our code that caused access to freed memory, and I have now fixed this in commit 9f94294.
The bug has been present for several years and occurs on all platform. However it only occurs if the current tab when you close the options dialog is the Paths tab.