False positive for potentially memory leak after transferring ownership to C array storage of > 1 dimension

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False positive for potentially memory leak after transferring ownership to C array storage of > 1 dimension #19340

Open llvmbot opened 10 years ago

llvmbot commented 10 years ago


Bugzilla Link	18966
Version	3.3
OS	MacOS X
Attachments	Self contained .m file
Reporter	LLVM Bugzilla Contributor
CC	@belkadan

Extended Description

When retained objects are assigned into a C array of greater than 1 dimension in a longer lived scope, the objects a potential leak is reported. I have tried this with a static global 2d array and an instance ivar. Attached test case contains both flavors.

Note that the same error does not occur with a 1d array.

belkadan commented 10 years ago

Cloned to rdar://problem/16173744

belkadan commented 10 years ago

More data: if the second index is replaced by a constant, or the first index is replaced by 0, the warning goes away.

My guess is that the analyzer is just unable to represent the location "foo[x][y]", because it's "&foo + x * sizeof(foo[0]) + y".

llvmbot commented 10 years ago

assigned to @tkremenek