Commit Graph

49 Commits

Author SHA1 Message Date
Roman Lebedev 88b56caa0e [analyzer] Fix false negative on post-increment of uninitialized variable.
Summary:
Currently clang static analyzer does warn on:
```
int x;
x+=1;
x-=1;
x=x+1;
x=x-1;
```
But does warn on:
```
int x;
x++;
x--;
--x;
++x;
```

This differential should fix that.
Fixes https://bugs.llvm.org/show_bug.cgi?id=35419

Reviewers: dcoughlin, NoQ

Reviewed By: dcoughlin

Subscribers: NoQ, xazax.hun, szepet, cfe-commits, a.sidorin

Tags: #clang

Differential Revision: https://reviews.llvm.org/D40463

llvm-svn: 319411
2017-11-30 09:18:35 +00:00
Artem Dergachev b6a513d1b2 [analyzer] Fix memory error bug category capitalization.
It was written as "Memory Error" in most places and as "Memory error" in a few
other places, however it is the latter that is more consistent with
other categories (such as "Logic error").

rdar://problem/31718115

Differential Revision: https://reviews.llvm.org/D32702

llvm-svn: 302016
2017-05-03 11:47:13 +00:00
Dominic Chen 184c6242fa Reland 4: [analyzer] NFC: Update test infrastructure to support multiple constraint managers
Summary: Replace calls to %clang/%clang_cc1 with %clang_analyze_cc1 when invoking static analyzer, and perform runtime substitution to select the appropriate constraint manager, per D28952.

Reviewers: xazax.hun, NoQ, zaks.anna, dcoughlin

Subscribers: mgorny, rgov, mikhail.ramalho, a.sidorin, cfe-commits

Differential Revision: https://reviews.llvm.org/D30373

llvm-svn: 296895
2017-03-03 18:02:02 +00:00
Dominic Chen 09d66f7528 Revert "Reland 3: [analyzer] NFC: Update test infrastructure to support multiple constraint managers"
This reverts commit ea36f1406e1f36bf456c3f3929839b024128e468.

llvm-svn: 296841
2017-03-02 23:30:53 +00:00
Dominic Chen feaf9ff5ee Reland 3: [analyzer] NFC: Update test infrastructure to support multiple constraint managers
Summary: Replace calls to %clang/%clang_cc1 with %clang_analyze_cc1 when invoking static analyzer, and perform runtime substitution to select the appropriate constraint manager, per D28952.

Reviewers: xazax.hun, NoQ, zaks.anna, dcoughlin

Subscribers: mgorny, rgov, mikhail.ramalho, a.sidorin, cfe-commits

Differential Revision: https://reviews.llvm.org/D30373

llvm-svn: 296837
2017-03-02 23:05:45 +00:00
Dominic Chen 4a90bf8c3f Revert "Reland 2: [analyzer] NFC: Update test infrastructure to support multiple constraint managers"
This reverts commit f93343c099fff646a2314cc7f4925833708298b1.

llvm-svn: 296836
2017-03-02 22:58:06 +00:00
Dominic Chen 1cb0256a3c Reland 2: [analyzer] NFC: Update test infrastructure to support multiple constraint managers
Summary: Replace calls to %clang/%clang_cc1 with %clang_analyze_cc1 when invoking static analyzer, and perform runtime substitution to select the appropriate constraint manager, per D28952.

Reviewers: xazax.hun, NoQ, zaks.anna, dcoughlin

Subscribers: mgorny, rgov, mikhail.ramalho, a.sidorin, cfe-commits

Differential Revision: https://reviews.llvm.org/D30373

llvm-svn: 296835
2017-03-02 22:45:24 +00:00
Dominic Chen 00355a51d0 Revert "Reland: [analyzer] NFC: Update test infrastructure to support multiple constraint managers"
This reverts commit 1b28d0b10e1c8feccb971abb6ef7a18bee589830.

llvm-svn: 296422
2017-02-28 01:50:23 +00:00
Dominic Chen 59cd893320 Reland: [analyzer] NFC: Update test infrastructure to support multiple constraint managers
Summary: Replace calls to %clang/%clang_cc1 with %clang_analyze_cc1 when invoking static analyzer, and perform runtime substitution to select the appropriate constraint manager, per D28952.

Reviewers: xazax.hun, NoQ, zaks.anna, dcoughlin

Subscribers: mgorny, rgov, mikhail.ramalho, a.sidorin, cfe-commits

Differential Revision: https://reviews.llvm.org/D30373

llvm-svn: 296414
2017-02-28 00:02:36 +00:00
Dominic Chen 8589e10c30 Revert "[analyzer] NFC: Update test infrastructure to support multiple constraint managers"
This reverts commit 8e7780b9e59ddaad1800baf533058d2c064d4787.

llvm-svn: 296317
2017-02-27 03:29:25 +00:00
Dominic Chen 02064a3076 [analyzer] NFC: Update test infrastructure to support multiple constraint managers
Summary: Replace calls to %clang/%clang_cc1 with %clang_analyze_cc1 when invoking static analyzer, and perform runtime substitution to select the appropriate constraint manager, per D28952.

Reviewers: xazax.hun, NoQ, zaks.anna, dcoughlin

Subscribers: mgorny, rgov, mikhail.ramalho, a.sidorin, cfe-commits

Differential Revision: https://reviews.llvm.org/D30373

llvm-svn: 296312
2017-02-27 02:36:15 +00:00
Artem Dergachev 0c33406aaa [analyzer] Add "Assuming..." diagnostic pieces for unsupported conditions.
In the analyzer's path-sensitive reports, when a report goes through a branch
and the branch condition cannot be decided to be definitely true or false
(based on the previous execution path), an event piece is added that tells the
user that a new assumption is added upon the symbolic value of the branch
condition. For example, "Assuming 'a' is equal to 3".

The text of the assumption is hand-crafted in various manners depending on
the AST expression. If the AST expression is too complex and the text of
the assumption fails to be constructed, the event piece is omitted.
This causes loss of information and misunderstanding of the report.

Do not omit the event piece even if the expression is too complex;
add a piece with a generic text instead.

Differential Revision: https://reviews.llvm.org/D23300

llvm-svn: 283301
2016-10-05 08:19:49 +00:00
Devin Coughlin e949add687 [analyzer] Update RegionStoreManager::getBinding to handle BlockDataRegions
Update RegionStoreManager::getBinding() to return UnknownVal when trying to get
the binding for a BlockDataRegion. Previously, getBinding() would try to cast the
BlockDataRegion to a TypedValueRegion and crash. This happened when a block
was passed as a parameter to an inlined function for which
StackHintGeneratorForSymbol::getMessage() tried to generate a stack hint message.

rdar://problem/21291971

llvm-svn: 252185
2015-11-05 18:56:42 +00:00
Gabor Horvath efec16307c [analyzer] Bug identification
This patch adds hashes to the plist and html output to be able to identfy bugs
for suppressing false positives or diff results against a baseline. This hash
aims to be resilient for code evolution and is usable to identify bugs in two
different snapshots of the same software. One missing piece however is a 
permanent unique identifier of the checker that produces the warning. Once that
issue is resolved, the hashes generated are going to change. Until that point
this feature is marked experimental, but it is suitable for early adoption.

Differential Revision: http://reviews.llvm.org/D10305 

Original patch by: Bence Babati!

llvm-svn: 251011
2015-10-22 11:53:04 +00:00
Gabor Horvath c18a11397c [Static Analyzer] The name of the checker that reports a bug is added
to the plist output. This check_name field does not guaranteed to be the
same as the name of the checker in the future.

Reviewer: Anna Zaks

Differential Revision: http://reviews.llvm.org/D6841

llvm-svn: 228624
2015-02-09 22:52:26 +00:00
Jordan Rose 5e2b3a30a0 [analyzer] Enable the new edge algorithm by default.
...but don't yet migrate over the existing plist tests. Some of these
would be trivial to migrate; others could use a bit of inspection first.
In any case, though, the new edge algorithm seems to have proven itself,
and we'd like more coverage (and more usage) of it going forwards.

llvm-svn: 183165
2013-06-03 23:00:19 +00:00
Anna Zaks e4cfcd4e41 [analyzer] Improve the malloc checker stack hint message
llvm-svn: 179580
2013-04-16 00:22:55 +00:00
Jordan Rose 526d93c55d [analyzer] Show "Returning from ..." note at caller's depth, not callee's.
Before:
  1. Calling 'foo'
    2. Doing something interesting
    3. Returning from 'foo'
  4. Some kind of error here

After:
  1. Calling 'foo'
    2. Doing something interesting
  3. Returning from 'foo'
  4. Some kind of error here

The location of the note is already in the caller, not the callee, so this
just brings the "depth" attribute in line with that.

This only affects plist diagnostic consumers (i.e. Xcode). It's necessary
for Xcode to associate the control flow arrows with the right stack frame.

<rdar://problem/13634363>

llvm-svn: 179351
2013-04-12 00:44:17 +00:00
Anna Zaks 07804ef87e [analyzer] Address Jordan’s review of r179219
llvm-svn: 179235
2013-04-10 22:56:33 +00:00
Anna Zaks 7c19abeba6 [analyzer] Cleanup leak warnings: do not print the names of variables from other functions.
llvm-svn: 179219
2013-04-10 21:42:02 +00:00
Anna Zaks a1de8567fc [analyzer] Shorten the malloc checker’s leak message
As per Ted’s suggestion!

llvm-svn: 178938
2013-04-06 00:41:36 +00:00
Anna Zaks 454a384e59 [analyzer] Only include uniqueling location as issue_hash when available
This makes us more optimistic when matching reports in a changing code
base. Addresses Jordan's feedback for r171825.

llvm-svn: 171884
2013-01-08 19:19:46 +00:00
Anna Zaks a043d0cef2 [analyzer] Include the bug uniqueing location in the issue_hash.
The issue here is that if we have 2 leaks reported at the same line for
which we cannot print the corresponding region info, they will get
treated as the same by issue_hash+description. We need to AUGMENT the
issue_hash with the allocation info to differentiate the two issues.

Add the "hash" (offset from the beginning of a function) representing
allocation site to solve the issue.

We might want to generalize solution in the future when we decide to
track more than just the 2 locations from the diagnostics.

llvm-svn: 171825
2013-01-08 00:25:29 +00:00
Anna Zaks 58b961d176 [analyzer] Plist: change the type of issue_hash from int to string.
This gives more flexibility to what could be stored as issue_hash.

llvm-svn: 171824
2013-01-08 00:25:22 +00:00
Jordan Rose e37ab50a6e [analyzer] Report leaks at the closing brace of a function body.
This fixes a few cases where we'd emit path notes like this:

  +---+
 1|   v
  p = malloc(len);
  ^   |2
  +---+

In general this should make path notes more consistent and more correct,
especially in cases where the leak happens on the false branch of an if
that jumps directly to the end of the function. There are a couple places
where the leak is reported farther away from the cause; these are usually
cases where there are several levels of nested braces before the end of
the function. This still matches our current behavior for when there /is/
a statement after all the braces, though.

llvm-svn: 168070
2012-11-15 19:11:43 +00:00
Jordan Rose b5b0fc196e [analyzer] Mark symbol values as dead in the environment.
This allows us to properly remove dead bindings at the end of the top-level
stack frame, using the ReturnStmt, if there is one, to keep the return value
live. This in turn removes the need for a check::EndPath callback in leak
checkers.

This does cause some changes in the path notes for leak checkers. Previously,
a leak would be reported at the location of the closing brace in a function.
Now, it gets reported at the last statement. This matches the way leaks are
currently reported for inlined functions, but is less than ideal for both.

llvm-svn: 168066
2012-11-15 19:11:27 +00:00
Ted Kremenek e7ec4ef48d Fix bug in BugReporter::RemoveUneededCalls() where "prunable"
PathDiagnosticEventPieces were *always* pruned.  Instead, they
are suppose to only be pruned if the entire call gets pruned.

llvm-svn: 163460
2012-09-08 07:18:18 +00:00
Ted Kremenek b724ea5c2e This test does not require --exact-match from FileCheck.
llvm-svn: 163456
2012-09-08 04:29:08 +00:00
Ted Kremenek b0d1c70258 Attempt (again) to stabilize the order of the emission of diagnostics
of the analyzer by using the FullProfile() of a PathDiagnostic
for ordering them.

llvm-svn: 163455
2012-09-08 04:26:37 +00:00
Anna Zaks b60908db3a [analyzer] Add experimental "issue hash" to the plist diagnostic.
CmpRuns.py can be used to compare issues from different analyzer runs.
Since it uses the issue line number to unique 2 issues, adding a new
line to the beginning of a file makes all issues in the file reported as
new. 

The hash will be an opaque value which could be used (along with the
function name) by CmpRuns to identify the same issues. This way, we only
fail to identify the same issue from two runs if the function it appears
in changes (not perfect, but much better than nothing).

llvm-svn: 158180
2012-06-08 00:04:43 +00:00
Ted Kremenek 54baf2e57d PlistDiagnostics: force the ranges for control-flow edges to be single locations, forcing
adjacent edges to have compatible ranges.  This simplifies the layout logic for some clients.

llvm-svn: 158028
2012-06-05 22:00:52 +00:00
Anna Zaks 62cce9e47d [analyzer] Do not highlight the range of the statement in case of leak.
We report a leak at a point a leaked variable is no longer accessible.
The statement that happens to be at that point is not relevant to the
leak diagnostic and, thus, should not be highlighted.

radar://11178519

llvm-svn: 156530
2012-05-10 01:37:40 +00:00
Ted Kremenek 170641b0e0 Refine analyzer diagnostics by adding an expression "cone-of-influence" to reverse track interesting
values through interesting expressions.  This allows us to map from interesting values in a caller
to interesting values in a caller, thus recovering some precision in diagnostics lost from IPA.

Fixes <rdar://problem/11327497>

llvm-svn: 155971
2012-05-02 00:31:29 +00:00
Anna Zaks 7e53bd6fb0 [analyzer] Run remove dead bindings right before leaving a function.
This is needed to ensure that we always report issues in the correct
function. For example, leaks are identified when we call remove dead
bindings. In order to make sure we report a callee's leak in the callee,
we have to run the operation in the callee's context.

This change required quite a bit of infrastructure work since:
 - We used to only run remove dead bindings before a given statement;
here we need to run it after the last statement in the function. For
this, we added additional Program Point and special mode in the
SymbolReaper to remove all symbols in context lower than the current
one.
 - The call exit operation turned into a sequence of nodes, which are
now guarded by CallExitBegin and CallExitEnd nodes for clarity and
convenience.

(Sorry for the long diff.)

llvm-svn: 155244
2012-04-20 21:59:08 +00:00
Ted Kremenek 5a10f08b52 Include the "issue context" (e.g. function or method) where a static analyzer issue occurred in the plist output.
Fixes <rdar://problem/11004527>

llvm-svn: 154030
2012-04-04 18:11:35 +00:00
Anna Zaks fc2e153444 [analyzer] Malloc: Utter the name of the leaked variable.
Specifically, we use the last store of the leaked symbol in the leak diagnostic.
(No support for struct fields since the malloc checker doesn't track those
yet.)

+ Infrastructure to track the regions used in store evaluations.
This approach is more precise than iterating the store to
obtain the region bound to the symbol, which is used in RetainCount
checker. The region corresponds to what is uttered in the code in the
last store and we do not rely on the store implementation to support
this functionality.

llvm-svn: 153212
2012-03-21 19:45:08 +00:00
Anna Zaks d42e828720 [analyzer] Re-enable the test disabled by r152969.
(The fix was committed in r152982.)

llvm-svn: 153210
2012-03-21 19:44:57 +00:00
Jordy Rose bf38f20e79 [analyzer] Mark a failed-realloc's result as an interesting symbol between the realloc call and the null check, so we get nicer path notes. Fixes a regression introduced by the diagnostic pruning added in r152361.
This is accomplished by calling markInteresting /during/ path diagnostic generation, and as such relies on deterministic ordering of BugReporterVisitors -- namely, that BugReporterVisitors are run in /reverse/ order from how they are added. (Right now that's a consequence of storing visitors in an ImmutableList, where new items are added to the front.) It's a little hacky, but it works for now.

I think this is the best we can do without storing the relation between the old and new symbols, and that would be a hit whether or not there ends up being an error.

llvm-svn: 153010
2012-03-18 07:43:35 +00:00
Anna Zaks ce690f4b24 [analyzer] This test is breaking windows bots, make it darwin-specific.
(The plist output does not match the one we expect, specifically we do
not detect that the interesting symbol is returned by a call.)

llvm-svn: 152969
2012-03-17 01:53:32 +00:00
Anna Zaks a7f457a5ea [analyzer] Shorten the stack hint diagnostic.
Do not display the standard "Returning from 'foo'", when a stack hint is
available.

llvm-svn: 152964
2012-03-16 23:44:28 +00:00
Anna Zaks cba4f298c6 [analyzer] Create symbol-aware stack hints (building upon r152837).
The symbol-aware stack hint combines the checker-provided message
with the information about how the symbol was passed to the callee: as
a parameter or a return value.

For malloc, the generated messages look like this :
"Returning from 'foo'; released memory via 1st parameter"
"Returning from 'foo'; allocated memory via 1st parameter"
"Returning from 'foo'; allocated memory returned"
"Returning from 'foo'; reallocation of 1st parameter failed"


(We are yet to handle cases when the symbol is a field in a struct or
an array element.)

llvm-svn: 152962
2012-03-16 23:24:20 +00:00
Ted Kremenek 1bdc2f41f9 Include full plist output in FileCheck test.
llvm-svn: 152858
2012-03-15 22:00:28 +00:00
Anna Zaks 1ff57d57e8 [analyzer] Allow checkers to supply call stack diagnostic hints for the
BugVisitor DiagnosticPieces.

When checkers create a DiagnosticPieceEvent, they can supply an extra
string, which will be concatenated with the call exit message for every
call on the stack between the diagnostic event and the final bug report.
(This is a simple version, which could be/will be further enhanced.)

For example, this is used in Malloc checker to produce the ",
which allocated memory" in the following example:

static char *malloc_wrapper() { // 2. Entered call from 'use'
    return malloc(12);    // 3. Memory is allocated
}

void use() {
    char *v;
    v = malloc_wrapper(); // 1. Calling 'malloc_wrappers'
        // 4. Returning from 'malloc_wrapper', which allocated memory
}                         // 5. Memory is never released; potential
memory leak

llvm-svn: 152837
2012-03-15 21:13:02 +00:00
Anna Zaks 6e5b48a6b4 [analyzer] Call enter/exit diagnostic should refer to caller/callee,
respectively.

llvm-svn: 152676
2012-03-13 22:15:55 +00:00
Ted Kremenek 1e809b4c4c [analyzer] Implement basic path diagnostic pruning based on "interesting" symbols and regions.
Essentially, a bug centers around a story for various symbols and regions.  We should only include
the path diagnostic events that relate to those symbols and regions.

The pruning is done by associating a set of interesting symbols and regions with a BugReporter, which
can be modified at BugReport creation or by BugReporterVisitors.

This patch reduces the diagnostics emitted in several of our test cases.  I've vetted these as
having desired behavior.  The only regression is a missing null check diagnostic for the return
value of realloc() in test/Analysis/malloc-plist.c.  This will require some investigation to fix,
and I have added a FIXME to the test case.

llvm-svn: 152361
2012-03-09 01:13:14 +00:00
Anna Zaks 0cdce4df76 [analyzer] Turn on by default the Malloc Checker and a couple of CString
checks:

- unix.Malloc - Checks for memory leaks, double free, use-after-free.
- unix.cstring.NullArg - Checks for null pointers passed as arguments to
CString functions + evaluates CString functions.
- unix.cstring.BadSizeArg - Checks for common anti-patterns in
strncat size argument.

llvm-svn: 150988
2012-02-20 21:10:37 +00:00
Anna Zaks 546c49c3b2 [analyzer] Malloc Checker: Clean up bug naming:
- Rename the category "Logic Error" -> "Memory Error".
 - Shorten all the messages.

llvm-svn: 150733
2012-02-16 22:26:12 +00:00
Anna Zaks 9eb7bc82ae [analyzer] Malloc Checker: Make the diagnostic visitor handle the case
of failing realloc. + Minor cleanups.

llvm-svn: 150732
2012-02-16 22:26:07 +00:00
Anna Zaks 95308d3798 [analyzer] Diagnostics: Ensure that the default end of diagnostic path
piece can always be generated.

The default end of diagnostic path piece was failing to generate on a
BlockEdge that was outgoing from a basic block without a terminator,
resulting in a very simple diagnostic being rendered (ex: no path
highlighting or custom visitors). Reuse another function, which is
essentially doing the same thing and correct it not to fail when a block
has no terminator.

llvm-svn: 150659
2012-02-16 03:41:01 +00:00