isuckatcs added inline comments.
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================
Comment at: test/Analysis/casts.c:166
+ *x = 1;
+ clang_analyzer_eval(u == 1); // expected-warning{{TRUE}}
+}
----------------
@NoQ why is this true for both x86_64 and i386?
On x86_64 `sizeof(int *) == 8` and `sizeof(int) == 4`. This means that `(*((int
*)(&x))) = (int)&u;` writes to the lower 4 bytes of `x` and leaves the upper 4
bytes uninitialized. See this [[ https://godbolt.org/z/E6ocPE9Gr | godbolt
example ]]. If I compile and run this function on my machine it segfaults.
On i386 `sizeof(int *) == 4` and `sizeof(int) == 4`, so on that platform this
example is correct. See on [[https://godbolt.org/z/GaW73Wod7 | godbolt]].
In the x86_64 case don't we want the analyzer to report a warning a instead, as
on that platform `u` is only partially initialized?
Repository:
rC Clang
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https://reviews.llvm.org/D46415/new/
https://reviews.llvm.org/D46415
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