I'm trying to remove unused options from the `Analyses.def` file, then
merge the rest of the useful options into the `AnalyzerOptions.def`.
Then make sure one can set these by an `-analyzer-config XXX=YYY` style
flag.
Then surface the `-analyzer-config` to the `clang` frontend;
After all of this, we can pursue the tablegen approach described
https://discourse.llvm.org/t/rfc-tablegen-clang-static-analyzer-engine-options-for-better-documentation/61488
In this patch, I'm proposing flag deprecations.
We should support deprecated analyzer flags for exactly one release. In
this case I'm planning to drop this flag in `clang-16`.
In the clang frontend, now we won't pass this option to the cc1
frontend, rather emit a warning diagnostic reminding the users about
this deprecated flag, which will be turned into error in clang-16.
Unfortunately, I had to remove all the tests referring to this flag,
causing a mass change. I've also added a test for checking this warning.
I've seen that `scan-build` also uses this flag, but I think we should
remove that part only after we turn this into a hard error.
Reviewed By: martong
Differential Revision: https://reviews.llvm.org/D126215
I'm trying to remove unused options from the `Analyses.def` file, then
merge the rest of the useful options into the `AnalyzerOptions.def`.
Then make sure one can set these by an `-analyzer-config XXX=YYY` style
flag.
Then surface the `-analyzer-config` to the `clang` frontend;
After all of this, we can pursue the tablegen approach described
https://discourse.llvm.org/t/rfc-tablegen-clang-static-analyzer-engine-options-for-better-documentation/61488
In this patch, I'm proposing flag deprecations.
We should support deprecated analyzer flags for exactly one release. In
this case I'm planning to drop this flag in `clang-16`.
In the clang frontend, now we won't pass this option to the cc1
frontend, rather emit a warning diagnostic reminding the users about
this deprecated flag, which will be turned into error in clang-16.
Unfortunately, I had to remove all the tests referring to this flag,
causing a mass change. I've also added a test for checking this warning.
I've seen that `scan-build` also uses this flag, but I think we should
remove that part only after we turn this into a hard error.
Reviewed By: martong
Differential Revision: https://reviews.llvm.org/D126215
Not only global variables can hold references to dead stack variables.
Consider this example:
void write_stack_address_to(char **q) {
char local;
*q = &local;
}
void test_stack() {
char *p;
write_stack_address_to(&p);
}
The address of 'local' is assigned to 'p', which becomes a dangling
pointer after 'write_stack_address_to()' returns.
The StackAddrEscapeChecker was looking for bindings in the store which
referred to variables of the popped stack frame, but it only considered
global variables in this regard. This patch relaxes this, catching
stack variable bindings as well.
---
This patch also works for temporary objects like:
struct Bar {
const int &ref;
explicit Bar(int y) : ref(y) {
// Okay.
} // End of the constructor call, `ref` is dangling now. Warning!
};
void test() {
Bar{33}; // Temporary object, so the corresponding memregion is
// *not* a VarRegion.
}
---
The return value optimization aka. copy-elision might kick in but that
is modeled by passing an imaginary CXXThisRegion which refers to the
parent stack frame which is supposed to be the 'return slot'.
Objects residing in the 'return slot' outlive the scope of the inner
call, thus we should expect no warning about them - except if we
explicitly disable copy-elision.
Reviewed By: NoQ, martong
Differential Revision: https://reviews.llvm.org/D107078
Summary:
When binding a temporary object to a static local variable, the analyzer would
complain about a dangling reference even though the temporary's lifetime should
be extended past the end of the function. This commit tries to detect these
cases and construct them in a global memory region instead of a local one.
Reviewers: jordan_rose
CC: cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D1133
llvm-svn: 187196
This doesn't appear to be the cause of the slowdown. I'll have to try a
manual bisect to see if there's really anything there, or if it's just
the bot itself taking on additional load. Meanwhile, this change helps
with correctness.
This changes an assertion and adds a test case, then re-applies r180638,
which was reverted in r180714.
<rdar://problem/13296133> and PR15863
llvm-svn: 180864
This seems to be causing quite a slowdown on our internal analyzer bot,
and I'm not sure why. Needs further investigation.
This reverts r180638 / 9e161ea981f22ae017b6af09d660bfc3ddf16a09.
llvm-svn: 180714
Casts to bool (and _Bool) are equivalent to checks against zero,
not truncations to 1 bit or 8 bits.
This improved reasoning does cause a change in the behavior of the alpha
BoolAssignment checker. Previously, this checker complained about statements
like "bool x = y" if 'y' was known not to be 0 or 1. Now it does not, since
that conversion is well-defined. It's hard to say what the "best" behavior
here is: this conversion is safe, but might be better written as an explicit
comparison against zero.
More usefully, besides improving our model of booleans, this fixes spurious
warnings when returning the address of a local variable cast to bool.
<rdar://problem/13296133>
llvm-svn: 180638
This is a follow-up to r175830, which made sure a temporary object region
created for, say, a struct rvalue matched up with the initial bindings
being stored into it. This does the same for the case in which the AST
actually tells us that we need to create a temporary via a
MaterializeObjectExpr. I've unified the two code paths and moved a static
helper function onto ExprEngine.
This also caused a bit of test churn, causing us to go back to describing
temporary regions without a 'const' qualifier. This seems acceptable; it's
our behavior from a few months ago.
<rdar://problem/13265460> (part 2)
llvm-svn: 175854
of a local variable, make sure we don't infinitely recurse when the
reference binds to itself.
e.g:
int* func() {
int& i = i; // assign non-exist variable to a reference which has same name.
return &i; // return pointer
}
rdar://11345441
llvm-svn: 155856
Also convert stack-addr-ps.cpp to use the analyzer instead of just Sema, now
that it doesn't crash, and extract the stack-block test into another file since
it errors, and that prevents the analyzer from running.
llvm-svn: 138613