Question about NEW throwing in MFC app
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We are all aware that by default VC++ implementation of NEW does not throw an exception (as it should based on C++ standards). MSDN has an article related to using set_new_handler() to make new throw std::bad_alloc when it fails instead of returning NULL. My question is how is that handled in an MFC app? For instance lets say you have a method named Foo(), and Foo() might throw std::bad_alloc due to it calling new internally. If you called Foo() from an MFC class method you override, and did not have a try/catch, would MFC catch the bad_alloc? In fact, what impact does it have at all on MFC if you change NEW to throw? I'm also curious how other developers handle NEW... Do you leave it returning NULL by default? If so, won't that cause problems if you use STL and an STL method calls new and it throws?
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We are all aware that by default VC++ implementation of NEW does not throw an exception (as it should based on C++ standards). MSDN has an article related to using set_new_handler() to make new throw std::bad_alloc when it fails instead of returning NULL. My question is how is that handled in an MFC app? For instance lets say you have a method named Foo(), and Foo() might throw std::bad_alloc due to it calling new internally. If you called Foo() from an MFC class method you override, and did not have a try/catch, would MFC catch the bad_alloc? In fact, what impact does it have at all on MFC if you change NEW to throw? I'm also curious how other developers handle NEW... Do you leave it returning NULL by default? If so, won't that cause problems if you use STL and an STL method calls new and it throws?
MFC has its own override of
operator newthat throws aCMemoryException. --Mike-- I'm bored... Episode I bored. 1ClickPicGrabber - Grab & organize pictures from your favorite web pages, with 1 click! My really out-of-date homepage Sonork-100.19012 Acid_Helm -
MFC has its own override of
operator newthat throws aCMemoryException. --Mike-- I'm bored... Episode I bored. 1ClickPicGrabber - Grab & organize pictures from your favorite web pages, with 1 click! My really out-of-date homepage Sonork-100.19012 Acid_HelmYep, and that is what happens when MFC calls new and it fails. But what happens if you call STL or your own funtions from within an MFC function override and your new handler is called throwing bad_alloc? It appears that MFC wont catch it, you will get an unhandled exception. If you try to recover from it, you might leak MFC resources. PS: Did this change in VC .NET? Or does new still return NULL?