Summary:
Creating a persistent reference to an Activity leads to a nasty form of memory leaks (see http://android-developers.blogspot.com/2009/01/avoiding-memory-leaks.html, https://corner.squareup.com/2015/05/leak-canary.html). There are many ways to create a bad persistent reference to an Activity, but the most obvious one is via a static field.
This diff implements a very simple form of Activity leak checking by inspecting postconditions to see if a subtype of Activity is reachable from a static field (and it reports an error if so). This is a very simple and limited form of leak checking that does not understand the Android lifecycle at all. In particular, if one creates a persistent reference to an Activity and then nulls it out in `onDestroy` (a reasonably common pattern), this approach will wrongly report a bug.
Summary:
This commit is the result of
`find infer/src -name '*.ml' -or -name '*.mli' -exec ocp-indent -i \{\} \;`
and
`INFER_CHECK_COPYRIGHT=1 InferPrint`
Summary:
@public
This adds basic support for function attributes in Sil, and for translating
attributes from the clang frontend to these new Sil attributes. For now only
the sentinel attribute is translated.
Note that attributes normally have parameters, but they are currently missing
from the clang plugin.
Test Plan:
Add
(match Sil.get_sentinel_func_attribute_value (Cfg.Procdesc.get_attributes callee_pdesc).Sil.func_attributes with
| Some _ -> L.out "found sentinel attribute!\n"
| _ -> ());
between lines 947 and 948 of symbExec.ml, then analyze a file containing:
int add_all_ints(int a, ...) __attribute__ ((sentinel));
int foo(void) { return add_all_ints(1, 2, 3, (void *)0); }
then `grep 'found sentinel' infer-out/log/analyzer_out`
-> the sentinel attribute is correctly passed from the frontend to the backend.