The analyzer does not model C++ temporary destructors completely and so
reports false alarms about leaks of memory allocated by the internals of
shared_ptr:
std::shared_ptr<int> p(new int(1));
p = nullptr; // 'Potential leak of memory pointed to by field __cntrl_'
This patch suppresses all diagnostics where the end of the path is inside
a method in std::shared_ptr.
It also reorganizes the tests for suppressions in the C++ standard library
to use a separate simulated header for library functions with bugs
that were deliberately inserted to test suppression. This will prevent
other tests from using these as models.
rdar://problem/23652766
llvm-svn: 274691
The analyzer reports a shift by a negative value in the constructor. The bug can
be easily triggered by calling std::random_shuffle on a vector
(<rdar://problem/19658126>).
(The shift by a negative value is reported because __w0_ gets constrained to
63 by the conditions along the path:__w0_ < _WDt && __w0_ >= _WDt-1,
where _WDt is 64. In normal execution, __w0_ is not 63, it is 1 and there is
no overflow. The path is infeasible, but the analyzer does not know about that.)
llvm-svn: 256886
This means always walking the whole call stack for the end path node, but
we'll assume that's always fairly tractable.
<rdar://problem/15952973>
llvm-svn: 200980
This is similar to r194004: because we can't reason about the data structure
invariants of std::basic_string, the analyzer decides it's possible for an
allocator to be used to deallocate the string's inline storage. Just ignore
this by walking up the stack, skipping past methods in classes with
"allocator" in the name, and seeing if we reach std::basic_string that way.
PR17866
llvm-svn: 194764
The motivation is to suppresses false use-after-free reports that occur when calling
std::list::pop_front() or std::list::pop_back() twice. The analyzer does not
reason about the internal invariants of the list implementation, so just do not report
any of warnings in std::list.
Fixes radar://14317928.
llvm-svn: 185609
This is a heuristic to make up for the fact that the analyzer doesn't
model C++ containers very well. One example is modeling that
'std::distance(I, E) == 0' implies 'I == E'. In the future, it would be
nice to model this explicitly, but for now it just results in a lot of
false positives.
The actual heuristic checks if the base type has a member named 'begin' or
'iterator'. If so, we treat the constructors and destructors of that type
as opaque, rather than inlining them.
This is intended to drastically reduce the number of false positives
reported with experimental destructor support turned on. We can tweak the
heuristic in the future, but we'd rather err on the side of false negatives
for now.
<rdar://problem/13497258>
llvm-svn: 178516
The idea is to eventually place all analyzer options under
"analyzer-config". In addition, this lays the ground for introduction of
a high-level analyzer mode option, which will influence the
default setting for IPAMode.
llvm-svn: 173385
'Inputs' subdirectory.
The general desire has been to have essentially all of the non-test
input files live in such directories, with some exceptions for obvious
and common patterns like 'foo.c' using 'foo.h'.
This came up because our distributed test runner couldn't find some of
the headers, for example with stl.cpp.
No functionality changed, just shuffling around here.
llvm-svn: 163674
This is a (heavy-handed) solution to PR13724 -- until we know we can do
a good job inlining the STL, it's best to be consistent and not generate
more false positives than we did before. We can selectively whitelist
certain parts of the 'std' namespace that are known to be safe.
This is controlled by analyzer config option 'c++-stdlib-inlining', which
can be set to "true" or "false".
This commit also adds control for whether or not to inline any templated
functions (member or non-member), under the config option
'c++-template-inlining'. This option is currently on by default.
llvm-svn: 163548
