Previously, the warning would erroneously fire on this:
for (Test *a in someArray)
use(a.weakProp);
...because it looks like the same property is being accessed over and over.
However, clearly this is not the case. We now ignore loops like this for
local variables, but continue to warn if the base object is a parameter,
global variable, or instance variable, on the assumption that these are
not repeatedly usually assigned to within loops.
Additionally, do-while loops where the condition is 'false' are not really
loops at all; usually they're just used for semicolon-swallowing macros or
using "break" like "goto".
<rdar://problem/12578785&12578849>
llvm-svn: 166942
Our one basic suppression heuristic is to assume that functions do not
usually return NULL. However, when one of the arguments is NULL it is
suddenly much more likely that NULL is a valid return value. In this case,
we don't suppress the report here, but we do attach /another/ visitor to
go find out if this NULL argument also comes from an inlined function's
error path.
This new behavior, controlled by the 'avoid-suppressing-null-argument-paths'
analyzer-config option, is turned off by default. Turning it on produced
two false positives and no new true positives when running over LLVM/Clang.
This is one of the possible refinements to our suppression heuristics.
<rdar://problem/12350829>
llvm-svn: 166941
Additionally, don't collect PostStore nodes -- they are often used in
path diagnostics.
Previously, we tried to track null arguments in the same way as any other
null values, but in many cases the necessary nodes had already been
collected (a memory optimization in ExplodedGraph). Now, we fall back to
using the value of the argument at the time of the call, which may not
always match the actual contents of the region, but often will.
This is a precursor to improving our suppression heuristic.
<rdar://problem/12350829>
llvm-svn: 166940
ELF subtarget.
The existing description string is moved from PPC64TargetInfo to its
DarwinTargetInfo subclass, to avoid any changes to the Darwin ABI.
PPC64TargetInfo now has two possible description strings: one for FreeBSD,
which requires 8-byte alignment, and a default string that requires
16-byte alignment.
I've added a test for PPC64 Linux to verify the 16-byte alignment. If
somebody wants to add a separate test for FreeBSD, that would be great.
Note that there is a companion patch to update the alignment information
in LLVM, which I am committing now as well.
llvm-svn: 166927
whether the initializer is value-dependent rather than whether we are in a
dependent context. This allows us to detect some errors sooner, and fixes a
crash-on-invalid if a dependent type leaks out to a non-dependent context in
error recovery.
llvm-svn: 166898
might have been used in constant expressions, rather than suppressing it for
variables which are const. The important thing here is that such variables
can have their values used without actually being marked as 'used'.
llvm-svn: 166896
doesn't include padding up to the alignment of the record, take this
as a cue that the alignment of the record should (conservatively) be
set to 1. This is similar to other the other cues we use to determine
that the record has a lower alignment, e.g., that the
externally-supplied layout places fields at lower offsets than we
would. Fixes <rdar://problem/12582052>; test case in LLDB.
llvm-svn: 166824
extern "C", its method definitions must be IRGen'ed
before meta-data for class is generated. Otherwise,
IRGen crashes (to say the least).
// rdar://12581683
llvm-svn: 166809
varargs parameter passing.
A strict reading of the ABI indicates that any argument with alignment greater
than 8 may require skipping doublewords in the parameter save area to align
the argument, and hence require skipping GPRs. In practice, this is not done
by GCC. The alignment restriction is used for internal alignment of a
structure, but a structure with 16-byte alignment, for example, is not
itself 16-byte aligned in the parameter save area. Although this is messy,
it has become the de facto standard used in building existing libraries.
My initial varargs support followed the ABI language, but not the de facto
standard. Running the GCC compatibility test suite exposed this issue, and
indeed showed that LLVM didn't pass parameters self-consistently with my
original logic. Removing the additional alignment logic allows the affected
tests to now pass.
I modified the ppc64-varargs-struct.c test case to remove the existing test
for generation of alignment code, which is no longer appropriate.
Built and tested on powerpc64-unknown-linux-gnu with no new regressions.
llvm-svn: 166805
only actually get the answer right if there was only a single
anonymous struct/union at that level. This is part of
<rdar://problem/11904570>; the test will go into LLDB itself.
llvm-svn: 166781
This code checks the ASM string to see if the output size is able to fit within
the variable specified as the output. For instance, scalar-to-vector conversions
may not really work. It's on by default, but can be turned off with a flag if
you think you know what you're doing.
This is placed under a flag ('-Wasm-operand-widths') and flag group ('-Wasm').
<rdar://problem/12284092>
llvm-svn: 166737
path notes for cases where a value may be assumed to be null, etc.
Instead of having redundant diagnostics, do a pass over the generated
PathDiagnostic pieces and remove notes from TrackConstraintBRVisitor
that are already covered by ConditionBRVisitor, whose notes tend
to be better.
Fixes <rdar://problem/12252783>
llvm-svn: 166728
the macros that are #define'd or #undef'd on the command line. This
checking happens much earlier than the current macro-definition
checking and is far cleaner, because it does a direct comparison
rather than a diff of the predefines buffers. Moreover, it allows us
to use the result of this check to skip over PCH files within a
directory that have non-matching -D's or -U's on the command
line. Finally, it improves the diagnostics a bit for mismatches,
fixing <rdar://problem/8612222>.
The old predefines-buffer diff'ing will go away in a subsequent commit.
llvm-svn: 166641
Many of our tests specify triples that are not built into clang.
In this commit we allow clang to fail loading the triple if we are only
using clang to emit llvm ir.
llvm-svn: 166543
After every 1000 CFGElements processed, the ExplodedGraph trims out nodes
that satisfy a number of criteria for being "boring" (single predecessor,
single successor, and more). Rather than controlling this with a cc1 option,
which can only disable this behavior, we now have an analyzer-config option,
'graph-trim-interval', which can change this interval from 1000 to something
else. Setting the value to 0 disables reclamation.
The next commit relies on this behavior to actually test anything.
llvm-svn: 166528
the various stakeholders bump up the reference count. In particular,
the diagnostics engine now keeps the DiagnosticOptions object alive.
llvm-svn: 166508
defined without a previous declaration. This is similar to
-Wmissing-prototypes, but for variables instead of functions.
Patch by Ed Schouten.
llvm-svn: 166498
check each of the files within that directory to determine if any of
them is an AST file that matches the language and target options. If
so, the first matching AST file is loaded. This fixes a longstanding
discrepency with GCC's precompiled header implementation.
llvm-svn: 166469
Quentin Colombet