visual studio 2010 - Undefined behaviour in C++ asserts: accessing an invalid/null pointer -

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under visual c++ 2010, following snippet hides dubious behaviour:

cobject* myobjectptr = cobjectfactory::makeanobject(); assert( myobjectptr->candosomework() ); // myobjectptr can null due logical errors

the following snippet, when placed in function, did not trigger assert when pointer null , function returned immediately. aside null pointer check obvious fix suggest, made code behave in such way? shouldn't complain memory access violation error if error occurs within assert?

myobjectptr->candosomework()

if candosomework not virtual function compiler rewrites c_object::candosomework(myobjectptr)

this doesn't involve dereference of object pointer @ won't crash or fail. if it's virtual function crash use pointer find vtable.

of course none of guaranteed in standard, it's undefined behavour, explains seeing happen.


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