False positive on dereference of null pointer warning

[llvmbot]

Bugzilla Link	15166
Version	unspecified
OS	MacOS X
Reporter	LLVM Bugzilla Contributor
CC	@belkadan

Extended Description

Using the static analyzer from the checker-270 build for MacOSX on the following C++ source:

============================ void set_x(void *&);

int foo(void) { int *x = 0;

set_x((void *&)x);
return *x;

}

results in:

warning: Dereference of null pointer (loaded from variable 'x')

This doesn't happen if the "void" is replaced by "int".

[llvmbot]

I agree it's likely rare, but it's used in Intel's Graphics driver.

[belkadan]

Thanks for the full bug report. Tracked in rdar://problem/11630894.

I will note that this use case is fairly rare and so it's not a high priority right now. Sorry!

[llvmbot]

assigned to @tkremenek