Passing a pointer to an uninitialized memory buffer is normally okay,
but if the function is declared to take a pointer-to-const then it's
very unlikely it will be modifying the buffer. In this case the analyzer
should warn that there will likely be a read of uninitialized memory.
This doesn't check all elements of an array, only the first one.
It also doesn't yet check Objective-C methods, only C functions and
C++ methods.
This is controlled by a new check: alpha.core.CallAndMessageUnInitRefArg.
Patch by Per Viberg!
llvm-svn: 203822
Like the binary operator check of r201702, this actually checks the
condition of every if in a chain against every other condition, an
O(N^2) operation. In most cases N should be small enough to make this
practical, and checking all cases like this makes it much more likely
to catch a copy-paste error within the same series of branches.
Part of IdenticalExprChecker; patch by Daniel Fahlgren!
llvm-svn: 203585
null comparison when the pointer is known to be non-null.
This catches the array to pointer decay, function to pointer decay and
address of variables. This does not catch address of function since this
has been previously used to silence a warning.
Pointer to bool conversion is under -Wbool-conversion.
Pointer to null comparison is under -Wtautological-pointer-compare, a sub-group
of -Wtautological-compare.
void foo() {
int arr[5];
int x;
// warn on these conditionals
if (foo);
if (arr);
if (&x);
if (foo == null);
if (arr == null);
if (&x == null);
if (&foo); // no warning
}
llvm-svn: 202216
For now, just ignore them. Later, we could try looking through LazyCompoundVals,
but we at least shouldn't crash.
<rdar://problem/16153464>
llvm-svn: 202212
Somehow both Daniel and I missed the fact that while loops are only identical
if they have identical bodies.
Patch by Daniel Fahlgren!
llvm-svn: 201829
IdenticalExprChecker now warns if any expressions in a logical or bitwise
chain (&&, ||, &, |, or ^) are the same. Unlike the previous patch, this
actually checks all subexpressions against each other (an O(N^2) operation,
but N is likely to be small).
Patch by Daniel Fahlgren!
llvm-svn: 201702
This extends the checks for identical expressions to handle identical
statements, and compares the consequent and alternative ("then" and "else")
branches of an if-statement to see if they are identical, treating a single
statement surrounded by braces as equivalent to one without braces.
This does /not/ check subsequent branches in an if/else chain, let alone
branches that are not consecutive. This may improve in a future patch, but
it would certainly take more work.
Patch by Daniel Fahlgren!
llvm-svn: 201701
This will let us stage in the modeling of operator new. The -analyzer-config
opton 'c++-inline-allocators' is currently off by default.
Patch by Karthik Bhat!
llvm-svn: 201122
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
redeclaration, not just when looking them up for a use -- we need the implicit
declaration to appropriately check various properties of them (notably, whether
they're deleted).
llvm-svn: 200729
Due to statement expressions supported as GCC extension, it is possible
to put 'break' or 'continue' into a loop/switch statement but outside
its body, for example:
for ( ; ({ if (first) { first = 0; continue; } 0; }); )
This code is rejected by GCC if compiled in C mode but is accepted in C++
code. GCC bug 44715 tracks this discrepancy. Clang used code generation
that differs from GCC in both modes: only statement of the third
expression of 'for' behaves as if it was inside loop body.
This change makes code generation more close to GCC, considering 'break'
or 'continue' statement in condition and increment expressions of a
loop as it was inside the loop body. It also adds error for the cases
when 'break'/'continue' appear outside loop due to this syntax. If
code generation differ from GCC, warning is issued.
Differential Revision: http://llvm-reviews.chandlerc.com/D2518
llvm-svn: 199897
If there are non-trivially-copyable types /other/ than C++ records, we
won't have a synthesized copy expression, but we can't just use a simple
load/return.
Also, add comments and shore up tests, making sure to test in both ARC
and non-ARC.
llvm-svn: 199869
Citation: C++11 [expr.shift]p1 (and the equivalent text in C11).
This fixes PR18073, but the right thing to do (as noted in the FIXME) is to
have a real checker for too-large shifts.
llvm-svn: 199405
test the CC1 layer.
This actually uncovered that the test semes to no longer be passing for
the reasons intended. =[ The name of the test would lead me to believe
that it should be testing the semantics of noreturn in the static
analyzer.... but there are in fact no -verify assertions about noreturn
that i can find. And the noreturn checker is no longer in 'alpha.core'.
It is in 'core.builtins'. The test *does* have one assertion for a null
dereference warning. This *also* isn't in 'alpha.core', but the driver
inserts a pile of other checker packages, including 'core' which has
this warning.
So I have switch the RUN line to actually do the minimal thing that this
test currently exercises, but someone who works on the static analyzer
should probably look at this and either nuke it or move it to actually
check the noreturn behavior.
llvm-svn: 199307
In preparation for making the Win32 triple imply MS ABI mode,
make all tests pass in this mode, or make them use the Itanium
mode explicitly.
Differential Revision: http://llvm-reviews.chandlerc.com/D2401
llvm-svn: 199130
In an expression like "new (a, b) Foo(x, y)", two things happen:
- Memory is allocated by calling a function named 'operator new'.
- The memory is initialized using the constructor for 'Foo'.
Currently the analyzer only models the second event, though it has special
cases for both the default and placement forms of operator new. This patch
is the first step towards properly modeling both events: it changes the CFG
so that the above expression now generates the following elements.
1. a
2. b
3. (CFGNewAllocator)
4. x
5. y
6. Foo::Foo
The analyzer currently ignores the CFGNewAllocator element, but the next
step is to treat that as a call like any other.
The CFGNewAllocator element is not added to the CFG for analysis-based
warnings, since none of them take advantage of it yet.
llvm-svn: 199123
...by synthesizing their body to be "return self->_prop;", with an extra
nudge to RetainCountChecker to still treat the value as +0 if we have no
other information.
This doesn't handle weak properties, but that's mostly correct anyway,
since they can go to nil at any time. This also doesn't apply to properties
whose implementations we can't see, since they may not be backed by an
ivar at all. And finally, this doesn't handle properties of C++ class type,
because we can't invoke the copy constructor. (Sema has actually done this
work already, but the AST it synthesizes is one the analyzer doesn't quite
handle -- it has an rvalue DeclRefExpr.)
Modeling setters is likely to be more difficult (since it requires
handling strong/copy), but not impossible.
<rdar://problem/11956898>
llvm-svn: 198953
...rather somewhere in the destructor when we try to access something and
realize the object has already been deleted. This is necessary because
the destructor is processed before the 'delete' itself.
Patch by Karthik Bhat!
llvm-svn: 198779
...even though the argument is declared "const void *", because this is
just a way to pass pointers around as objects. (Though NSData is often
a better one.)
PR18262
llvm-svn: 198710
This checker has not been updated to work with interprocedural analysis,
and actually contains both logical correctness issues but also
memory bugs. We can resuscitate it from version control once there
is focused interest in making it a real viable checker again.
llvm-svn: 198476
We have assertions for this, but a few edge cases had snuck through where
we were still unconditionally using 'int'.
<rdar://problem/15703011>
llvm-svn: 197733
Fixes <rdar://problem/15584219> and <rdar://problem/12241361>.
This change looks large, but all it does is reuse and consolidate
the delayed diagnostic logic for deprecation warnings with unavailability
warnings. By doing so, it showed various inconsistencies between the
diagnostics, which were close, but not consistent. It also revealed
some missing "note:"'s in the deprecated diagnostics that were showing
up in the unavailable diagnostics, etc.
This change also changes the wording of the core deprecation diagnostics.
Instead of saying "function has been explicitly marked deprecated"
we now saw "'X' has been been explicitly marked deprecated". It
turns out providing a bit more context is useful, and often we
got the actual term wrong or it was not very precise
(e.g., "function" instead of "destructor"). By just saying the name
of the thing that is deprecated/deleted/unavailable we define
this issue away. This diagnostic can likely be further wordsmithed
to be shorter.
llvm-svn: 197627
cstring, converted to NSString, produce the
matching AST for it. This also required some
refactoring of the previous code. // rdar://14106083
llvm-svn: 197605
This patch was submitted to the list for review and didn't receive a LGTM.
(In fact one explicit objection and one query were raised.)
This reverts commit r197295.
llvm-svn: 197299
Previously, a line like
// expected-error-re {{foo}}
treats the entirety of foo as a regex. This is inconvenient when matching type
names containing regex characters. For example, to match
"void *(class test8::A::*)(void)" inside such a regex, one would have to type
"void \*\(class test8::A::\*\)\(void\)".
This patch changes the semantics of expected-error-re to only treat the parts
of the directive wrapped in double curly braces as regexes. This avoids the
escaping problem and leads to nicer patterns for those cases; see e.g. the
change to test/Sema/format-strings-scanf.c.
(The balanced search for closing }} of a directive also makes us handle the
full directive in test\SemaCXX\constexpr-printing.cpp:41 and :53.)
Differential Revision: http://llvm-reviews.chandlerc.com/D2388
llvm-svn: 197092
Warn if both result expressions of a ternary operator (? :) are the same.
Because only one of them will be executed, this warning will fire even if
the expressions have side effects.
Patch by Anders Rönnholm and Per Viberg!
llvm-svn: 196937