Summary:
Next step to issue deduplication: do not keep safety conditions that are subsumed by others.
Only do it if they do not have infinite bound: replacing `0 < size` by `1 < size` is ok, but replacing it by `+oo < size` is not because it looks much more like a lack of precision.
Reviewed By: skcho
Differential Revision: D5978455
fbshipit-source-id: acc2384
Summary:
A specific type of alias is added for the vector::empty() result and it is used at pruning.
Now, there are two types of aliases:
- "simple" alias: x=y
- "empty" alias: x=v.empty() and y=v.size
So, if x!=0, y is pruned by (y=0). Otherwise, i.e., x==0, y is pruned by (y>=1).
Reviewed By: mbouaziz
Differential Revision: D6004968
fbshipit-source-id: bb8d50d
Summary:
Move Inferbo safety conditions to their own file.
Split the old `Condition.t` to a condition together with a trace.
This will ease having: different kind of condition and several traces for the same condition (see following diff)
Reviewed By: jvillard
Differential Revision: D5942030
fbshipit-source-id: d74a612
Summary:
Bottom bounds do not make sense (what is the meaning of `[_|_; 1]`?), let's get rid of them.
`Bot` was useful for substitution though, with a special meaning, use `bottom_lifted` for that case.
Reviewed By: skcho
Differential Revision: D5941796
fbshipit-source-id: 5778255
Summary: A bottom interval in a safety condition doesn't make sense. Let's not allow it at all.
Reviewed By: skcho
Differential Revision: D5941552
fbshipit-source-id: 6bd2a65
Summary: Use `pp` functions until it needs to be turned into a string.
Reviewed By: jvillard
Differential Revision: D5941473
fbshipit-source-id: 87ca9df
Summary:
The interval bound of the abstract domain is extended.
`[min|max](int, symbol)` => `int [+|-] [min|max](int, symbol)`
As a result, `vector::empty` can be modelled to return a more precise value: `1 - min(1, size)`.
Reviewed By: mbouaziz
Differential Revision: D5899404
fbshipit-source-id: c8c3f49
Summary:
Read the documentation and it doesn't seem like these functions are guaranteed to choose the same value in different runs.
I hypothesize that these may be the source of flakiness in the thread-safety tests/smoke tests.
Reviewed By: jvillard
Differential Revision: D5794384
fbshipit-source-id: 02b7a96
Summary:
- failwith police: no more `failwith`. Instead, use `Logging.die`.
- Introduce the `SimpleLogging` module for dying from modules where `Logging`
cannot be used (usually because that would create a cyclic dependency).
- always log backtraces, and show backtraces on the console except for usage errors
- Also point out in the log file where the toplevel executions of infer happen
Reviewed By: jeremydubreil
Differential Revision: D5726362
fbshipit-source-id: d7a01fc
Summary:
Calling exit at the end of a proc does not create unreachable code, prior to this commit inferbo reports that it does.
We extend collect_instrs to detect when we're at the end of a procedure in C and not report on unreachable code if we call a procedure there.
Reviewed By: mbouaziz
Differential Revision: D5623637
fbshipit-source-id: 0d5f326
Summary:
Instead of a whitelist and blacklist and default issue types and default
blacklist and filtering, consider a simpler semantics where
1. checkers can be individually turned on or off on the command line
2. most checkers are on by default
3. `--no-filtering` turns all issue types on, but they can then be turned off again by further arguments
This provides a more flexible CLI and is similar to other options in the infer
CLI, where "global" behaviour is generally avoided.
Dynamically created checkers (eg, AL linters) cause some complications in the
implementation but I think the semantics is still clear.
Also change the name of the option to mention "issue types" instead of
"checks", since the latter can be confused with "checkers".
Reviewed By: jberdine
Differential Revision: D5583238
fbshipit-source-id: 21de476
Summary:
This commit avoids precision loss on pruning.
// x -> [s$1, s$2]
if(x) { ... }
// x -> ?
before: x -> [min(0, s$1), max(0, s$2)]
because two x values, [0, 0] (true case) and [s$1, s$2] (false case), were joined after the if branch.
after: x -> [s$1, s$2]
Reviewed By: mbouaziz
Differential Revision: D5431009
fbshipit-source-id: 14a9efe
Summary:
Problem: The analyzer did not know that the value of `v.size()` is an alias of `v.infer_size`, so `v.infer_size` is not pruned by the if condition. As a result it raises a false alarm.
void safe_access(std::vector<int> v) {
if (v.size() >= 10) {
v[9] = 1; // error: BUFFER_OVERRUN Offset: [9, 9] Size: [5, 5]
}
}
void call_safe_access_Good() {
std::vector<int> v(5, 0);
safe_access(v);
}
Solution: Adding alias for return value to the abstract domain.
Now Inferbo can prune `v.infer_size` because it knows that the value of `v.size()` is an alias of `v.infer_size`. There is already an alias domain in Inferbo, so we added a specific room for the retrun value.
Reviewed By: jvillard, mbouaziz
Differential Revision: D5396988
fbshipit-source-id: 4a4702c
Summary:
Conversion and reformat of infer source using ocamlformat
auto-formatting tool.
Current status:
- Because Reason does not handle docstrings, the output of the
conversion is not 'Warning 50'-clean, meaning that there are
docstrings with ambiguous placement. I'll need to manually fix
them just before landing.
Reviewed By: jvillard
Differential Revision: D5225546
fbshipit-source-id: 3bd2786
Summary:
:
Get rid of model location in reports.
The goal is to avoid changing `issues.exp` whenever a model is updated.
Reviewed By: jvillard
Differential Revision: D5356608
fbshipit-source-id: 88ecaba
Summary: This could generate enormous amounts of logs on medium-sized projects (eg rocksdb) when running with `--stats`. Review other debug levels in inferbo as well.
Reviewed By: mbouaziz
Differential Revision: D5364139
fbshipit-source-id: 5c8d206
Summary:
It instantiates fields of structures when a pointer to which is given
as a function parameter, e.g., `foo(&s);`.
Reviewed By: mbouaziz, jvillard
Differential Revision: D5337645
fbshipit-source-id: c06da29
Summary: Unknown library returns the unknown pointer as well as the top interval.
Reviewed By: mbouaziz, jvillard
Differential Revision: D5282669
fbshipit-source-id: 34c7e18
Summary:
:
Do not store dummy `_` into the stack.
This makes debugging a lot easier
Reviewed By: skcho
Differential Revision: D5275941
fbshipit-source-id: ce329a5
Summary:
After D5245416 I was taking a closer look and decided it's best to get rid of the `Interprocedural` module altogether.
Since jeremydubreil's refactoring to pass the summaries around everywhere, this module doesn't do much (it used to make sure the summary actually got stored to disk).
Client code is shorter and simpler without this module.
Reviewed By: mbouaziz
Differential Revision: D5255400
fbshipit-source-id: acd1c00
Summary: The docs for this said that it stores the summary to disk, which is no longer true. `compute_summary` is more descriptive of what it actually does now.
Reviewed By: jberdine
Differential Revision: D5245416
fbshipit-source-id: f5138cd
Summary:
Now that we can run several inter-procedural analyses at the same time, we should no longer use the function `Reporting.log_error_deprecated` as it logs the errors in the specs table. This specs table is normally used for caching and will be deprecated in favor of having a cache summaries for the callees in the `Ondemand` module (to avoid deserialising a callee more than once within the same process).
This revision just renames the reporting functions.
Reviewed By: sblackshear
Differential Revision: D5205009
fbshipit-source-id: b066549
Summary:
Change the API of `Logging` wrt to writing to files and to the console (see
changes in logging.mli).
Write only to one log file: infer-out/log. Prefix each line with the kind of
warning and the PID of the process emitting it. Writing with `O_APPEND` is
atomic so the file should not get garbled by concurrent writes. To get the
output of a single process, find out which one interests you by looking at
infer-out/log, then `grep ^[<PID>] infer-out/log`.
Introduce 3 log levels for debug output and command-line options to set them
for various categories individually.
Change tons of `"\n"` to `"@\n"` so the `Format` module is aware of newlines
without us having to look through every character of every logged string for
`\n` characters.
Reviewed By: mbouaziz
Differential Revision: D5165317
fbshipit-source-id: 93c922f
Summary: Allow type variables in `Typ.desc`. It will be used to store template type arguments.
Reviewed By: jberdine
Differential Revision: D5154757
fbshipit-source-id: 55b8e81
Summary:
- model `exit` as `Bottom`
- model `fgetc` as returning `[-1; 255]` rather than `[-1; +oo]`
- reduced the number of model functions for simple models
Reviewed By: KihongHeo
Differential Revision: D5137485
fbshipit-source-id: 943eeeb
Summary:
This diff fixes unintentional bottoms in pointer arithmetic of inferbo.
The pointer arithmetic on addresses of variables (not array) just returns
the operand.
Reviewed By: jvillard
Differential Revision: D5060424
fbshipit-source-id: 495d8b8
Summary:
Try and enforce the following rules:
- stderr is for updating the user about progress or errors
- Introduce Logging.progress that outputs to stderr, but honours --quiet
- Logging.stderr is as before
- Logging.out now prints to stderr (or to log files as before if set up) and
not stdout. If some information should go on stdout then the user should be
able to rely on it (ie, it's not just some progress message). For now only
the summary of the errors is printed on stdout by default.
- Logging.err* functions are gone. If the error is user-visible, it should be
Logging.stderr, or `failwith`. If not, go to the same log file as other
output, which personally I find much more convenient than having to dig through
2 log files every time I'm looking for some output.
Reviewed By: jberdine
Differential Revision: D5095720
fbshipit-source-id: 68999c9
Summary:
Previously all knowledge of the dynamic length of such arrays was lost to infer:
```
void foo(int len) {
int a[len];
}
```
The translation of this program would make no reference to `len` (except as a
param of `foo`).
Translate this "initialization" using the existing `__set_array_length` infer
builtin, as:
```
# Declare local a[_]
n$0 = len;
__set_array_length(a, len);
```
update-submodule: facebook-clang-plugins
Reviewed By: mbouaziz
Differential Revision: D4969446
fbshipit-source-id: dff860f
Summary:
This commit fixes a problem that the buffer overrun checker incorrectly
stops when a global variable (bottom) is involved in control flow.
In the new version, abstract memories return Top for unanalyzed abstract
variables.
Reviewed By: mbouaziz
Differential Revision: D5016447
fbshipit-source-id: 5132448
Summary:
An array has a static or dynamic length (number of elements), but it also has a
stride, determined by the type of the element: `sizeof(element_type)`. We don't
have a good `sizeof()` function available on SIL types, so record that stride
in the array type.
update-submodule: facebook-clang-plugins
Reviewed By: mbouaziz
Differential Revision: D4969697
fbshipit-source-id: 98e0670
Summary:
Ran the build with -w,-32 , delete code, repeat, until a fixpoint of no more warnings is reach.
Unfortunately we cannot fatal on w32 because ppx_compare can generate dead code (eg `compare_t` and only `compare` is used).
Reviewed By: mbouaziz
Differential Revision: D4945800
fbshipit-source-id: c95afb6
Summary:
`[a, b] < [a, _]` and `[_, a] < [b, a]` are most probably false (it comes from size < size)
Mark definitely unsatisfied conditions as B1, others as B2+
Reviewed By: KihongHeo, jvillard
Differential Revision: D4962107
fbshipit-source-id: ba8f469
Summary:
For now we just want to find bugs, let's do something smarter later (smash heap variables only when needed).
Depends on D4962107
Reviewed By: jvillard
Differential Revision: D4962121
fbshipit-source-id: 1b777a6
Summary:
Modify the type of `Exp.Sizeof ...` to include the value that the expression
evaluates to according to the compiler, or None if it cannot be known
statically.
Use this information in inferbo.
Mostly unused in the BiAbduction checker for now, although it could be useful
there too.
update-submodule: facebook-clang-plugins
Reviewed By: mbouaziz
Differential Revision: D4953634
fbshipit-source-id: be0999d
Summary:
Bottom means unreachable, not unknown.
Replace Bottom by Top in:
- unknown procedure return value
- unknown constant
- closure, exceptions
- when there are more formals than actuals
Depends on D4961989
Reviewed By: KihongHeo
Differential Revision: D4962006
fbshipit-source-id: e2a153d
Summary:
- Use Logging for logging
- Add a few extra debug (not ON by default)
- No space before colon
Depends on D4961957
Reviewed By: KihongHeo
Differential Revision: D4961989
fbshipit-source-id: 7c8697d
Summary:
- Bottom-lift abstract memory domain to express unreachable node
- Two cases to make a node unreachable
+ constant: when an evaluation result of condition expression is
bottom or false, e.g., "prune(0)".
+ alias: when the same structure e is compared to itself with "<",
">", and "!=", e.g., "prune(e < e)".
- Add test for the new prune (prune_constant.c, prune_alias.c)
- Debug the semantics of comparison
Reviewed By: mbouaziz
Differential Revision: D4938055
fbshipit-source-id: d0fadf0
Summary:
This is step further simplify the code to avoid cases where the summary of the procedure being analyzed can exist in two different versions:
# one version is the summary passed as parameter to every checker
# the other is a copy of the summary in the in-memory specs table
This diff implements:
# the analysis always run through the `Ondemand` module (was already the case before)
# the summary of the procedure being analyzed is created at the beginning of the on-demand analysis call
# all the checkers run in sequence, update their respective part of the payload and log errors to the error table
# the summary is store at the end of the on-demand analysis call
Reviewed By: sblackshear
Differential Revision: D4787414
fbshipit-source-id: 2d115c9
Summary: Writing the summaries to disk now happens automatically during the on-demand analysis calls. So, individual checkers do not need to worry anymore about when should the analysis summaries be written to disk for the interprocedural analysis to do the right thing.
Reviewed By: sblackshear
Differential Revision: D4764337
fbshipit-source-id: 63870db
Summary:
Changes every checker to take a summary as parameter and return the updated summary to the next checker. Since several operations, like `Reporting.log_*` are modifying the summary in memory by loading them from the in-memory cache of summaries, we currently need to rely on `Specs.get_summary_unsafe` to return the updated version of the summary.
This diff allows to change the API of `Reporting` to take a summary as input and progressively remove all the calls `Specs.get_summary_unsafe` independently from adding the possibility to run several checkers at the same time. The final objective to have every checker just passing around the summary of the procedure being analyzed, and having the in-memory cache only use to store the summaries of the callees.
Reviewed By: sblackshear
Differential Revision: D4649252
fbshipit-source-id: 98f7ca7
Summary:
Polymorphic models, and type environment refinements, need mutual
references between general types and struct types.
Reviewed By: cristianoc
Differential Revision: D4620076
fbshipit-source-id: f9d01e6
Summary: Being forced to separately define `pp_element`/`pp_key` is uneccessary and makes it more cumbersome to create a set/map from an existing module that already defines `pp`.
Reviewed By: jeremydubreil
Differential Revision: D4517308
fbshipit-source-id: 9b17c9c
Summary:
At one point I thought we'd want to have lots of different schedulers for things like exploring loops in different orders, but that hasn't materialized.
Let's make the common use-case simpler by hiding the `Scheduler` parameter inside the `AbstractInterpreter` module.
We can always expose `MakeWithScheduler` later if we want to.
Reviewed By: jberdine
Differential Revision: D4508095
fbshipit-source-id: 726e051
Mehdi Bouaziz
Sungkeun Cho
Sam Blackshear
Jules Villard
Greg Nisbet
Jeremy Dubreil
Josh Berdine
Kihong Heo
Andrzej Kotulski
Martino Luca
Kihong Heo
Cristiano Calcagno