@finally is still not implemented.
With this, clang can emit -Wreturn-type warnings for functions containing
@try/@catch (but not yet @finally), and -Wunreachable-code also works for those
functions.
The implementation is similar to D36914.
Part of PR46693.
Differential Revision: https://reviews.llvm.org/D112287
`[[clang::fallthrough]]` has meaning for the CFG, but all other
StmtAttrs we currently have don't. So omit them, as AttributedStatements
with children cause several issues and there's no benefit in including
them.
Fixes PR52103 and PR49454. See PR52103 for details.
Differential Revision: https://reviews.llvm.org/D111568
Modify the IfStmt node to suppoort constant evaluated expressions.
Add a new ExpressionEvaluationContext::ImmediateFunctionContext to
keep track of immediate function contexts.
This proved easier/better/probably more efficient than walking the AST
backward as it allows diagnosing nested if consteval statements.
Previously, information about `ConstructionContextLayer` was not
propagated thru causing the expression like:
Var c = (createVar());
To produce unrelated temporary for the `createVar()` result and conjure
a new symbol for the value of `c` in C++17 mode.
Reviewed By: steakhal
Patch By: tomasz-kaminski-sonarsource!
Differential Revision: https://reviews.llvm.org/D102835
These cases all follow the same pattern:
struct A {
friend class X;
//...
class X {};
};
But 'friend class X;' injects 'X' into the surrounding namespace scope,
rather than introducing a class member. So the second 'class X {}' is a
completely different type, which changes the meaning of the earlier name
'X' from '::X' to 'A::X'.
Additionally, the friend declaration is pointless -- members of a class
don't need to be befriended to be able to access private members.
Summary:
Array size expressions in typedef statements with a VLA
(variable-length array) are handled from now as in plain
(non-typedef) VLA declarations.
Type-aliases with VLA are handled too
(but main focus is on C code).
Reviewers: Szelethus, aaron.ballman, NoQ, xazax.hun
Reviewed By: aaron.ballman, xazax.hun
Subscribers: rnkovacs, NoQ, efriedma, xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, Szelethus, donat.nagy, dkrupp, gamesh411, Charusso, martong, ASDenysPetrov, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D77809
The CFGBlock::getLastCondition was not prepared for static initializer
branches.
This patch also revamps CFG unit tests. Earlier the lifetime of the AST
was smaller than the CFG. So all the AST pointers within the CFG blocks
were dangling. This was OK, since none of the tests dereferenced those
pointers. This was, however, a timed bomb. There were patches in the
past that were reverted partially due to this problem.
Differential revision: https://reviews.llvm.org/D71791
This is useful for clients that are relying on linearized CFGs for evaluating
subexpressions and want the default initializer to be evaluated properly.
The upcoming lifetime analysis is using this but it might also be useful
for the static analyzer at some point.
Differential Revision: https://reviews.llvm.org/D71642
Some AST nodes which stands for implicit initialization is shared. The analyzer
will do the same evaluation on the same nodes resulting in the same state. The
analyzer will "cache out", i.e. it thinks that it visited an already existing
node in the exploded graph. This is not true in this case and we lose coverage.
Since these nodes do not really require any processing from the analyzer
we just omit them from the CFG.
Differential Revision: https://reviews.llvm.org/D71371
Taking a value and the bitwise-or it with a non-zero constant will always
result in a non-zero value. In a boolean context, this is always true.
if (x | 0x4) {} // always true, intended '&'
This patch creates a new warning group -Wtautological-bitwise-compare for this
warning. It also moves in the existing tautological bitwise comparisons into
this group. A few other changes were needed to the CFGBuilder so that all bool
contexts would be checked. The warnings in -Wtautological-bitwise-compare will
be off by default due to using the CFG.
Fixes: https://bugs.llvm.org/show_bug.cgi?id=42666
Differential Revision: https://reviews.llvm.org/D66046
llvm-svn: 375318
In OpenMP constructs all counters are initialized and we should not emit
warnings about uninitialized privatized loop control variables.
llvm-svn: 375167
-Wtautological-overlap-compare and self-comparison from -Wtautological-compare
relay on detecting the same operand in different locations. Previously, each
warning had it's own operand checker. Now, both are merged together into
one function that each can call. The function also now looks through member
access and array accesses.
Differential Revision: https://reviews.llvm.org/D66045
llvm-svn: 372453
Allow this warning to detect a larger number of constant values, including
negative numbers, and handle non-int types better.
Differential Revision: https://reviews.llvm.org/D66044
llvm-svn: 372448
Seems like we never had these, so here we go! I also did some refactoring as I
was chasing a bug unrelated to this revision.
Differential Revision: https://reviews.llvm.org/D66715
llvm-svn: 371765
We're building the CFG from bottom to top, so when the return-value expression
has a non-trivial CFG on its own, we need to continue building from the entry
to the return-value expression CFG rather than from the block to which
we've just appended the return statement.
Fixes a false positive warning "control may reach end of non-void function".
llvm-svn: 370406
Respect C++17 copy elision; previously it would generate destructor calls
for elided temporaries, including in initialization and return statements.
Don't generate duplicate destructor calls for statement expressions.
Fix destructors in initialization lists and comma operators.
Improve printing of implicit destructors.
Patch by Nicholas Allegra!
Differential Revision: https://reviews.llvm.org/D66404
llvm-svn: 370247
Previously, collecting CFGElements in a set was practially impossible, because
both CFGBlock::operator[] and both the iterators returned it by value. One
workaround would be to collect the iterators instead, but they don't really
capture the concept of an element, and elements from different iterator types are incomparable.
This patch introduces CFGElementRef, a wrapper around a (CFGBlock, Index) pair,
and a variety of new iterators and iterator ranges to solve this problem.
I guess you could say that this patch took a couple iterations to get right :^)
Differential Revision: https://reviews.llvm.org/D65196
llvm-svn: 368883
Well, what is says on the tin I guess!
Some more changes:
* Move isInevitablySinking() from BugReporter.cpp to CFGBlock's interface
* Rename and move findBlockForNode() from BugReporter.cpp to
ExplodedNode::getCFGBlock()
Differential Revision: https://reviews.llvm.org/D65287
llvm-svn: 368836
1. raw_ostream supports ANSI colors so that you can write messages to
the termina with colors. Previously, in order to change and reset
color, you had to call `changeColor` and `resetColor` functions,
respectively.
So, if you print out "error: " in red, for example, you had to do
something like this:
OS.changeColor(raw_ostream::RED);
OS << "error: ";
OS.resetColor();
With this patch, you can write the same code as follows:
OS << raw_ostream::RED << "error: " << raw_ostream::RESET;
2. Add a boolean flag to raw_ostream so that you can disable colored
output. If you disable colors, changeColor, operator<<(Color),
resetColor and other color-related functions have no effect.
Most LLVM tools automatically prints out messages using colors, and
you can disable it by passing a flag such as `--disable-colors`.
This new flag makes it easy to write code that works that way.
Differential Revision: https://reviews.llvm.org/D65564
llvm-svn: 367649
Summary:
Added support for analysis of if clauses in the OpenMP directives to be
able to check for the use of uninitialized variables.
Reviewers: NoQ
Subscribers: guansong, jfb, jdoerfert, caomhin, kkwli0, cfe-commits
Tags: clang
Differential Revision: https://reviews.llvm.org/D64646
llvm-svn: 366211
Summary:
Some OpenMP clauses rely on the values of the variables. If the variable
is not initialized and used in OpenMP clauses that depend on the
variables values, it should be reported that the uninitialized variable
is used in the OpenMP clause expression.
This patch adds initial processing for uninitialized variables in OpenMP
constructs. Currently, it checks for use of the uninitialized variables
in the structured blocks.
Reviewers: NoQ, Szelethus, dcoughlin, xazax.hun, a.sidorin, george.karpenkov, szepet
Subscribers: rnkovacs, guansong, jfb, jdoerfert, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D64356
llvm-svn: 365786
getTerminatorCondition() returned a condition that may be outside of the
block, while the new function returns the proper one:
if (A && B && C) {}
Return C instead of A && B && C.
Differential Revision: https://reviews.llvm.org/D63538
llvm-svn: 365177
For the following terminator statement:
if (A && B && C && D)
The built CFG is the following:
[B5 (ENTRY)]
Succs (1): B4
[B1]
1: 10
2: j
3: [B1.2] (ImplicitCastExpr, LValueToRValue, int)
4: [B1.1] / [B1.3]
5: int x = 10 / j;
Preds (1): B2
Succs (1): B0
[B2]
1: C
2: [B2.1] (ImplicitCastExpr, LValueToRValue, _Bool)
T: if [B4.4] && [B3.2] && [B2.2]
Preds (1): B3
Succs (2): B1 B0
[B3]
1: B
2: [B3.1] (ImplicitCastExpr, LValueToRValue, _Bool)
T: [B4.4] && [B3.2] && ...
Preds (1): B4
Succs (2): B2 B0
[B4]
1: 0
2: int j = 0;
3: A
4: [B4.3] (ImplicitCastExpr, LValueToRValue, _Bool)
T: [B4.4] && ...
Preds (1): B5
Succs (2): B3 B0
[B0 (EXIT)]
Preds (4): B1 B2 B3 B4
However, even though the path of execution in B2 only depends on C's value,
CFGBlock::getCondition() would return the entire condition (A && B && C). For
B3, it would return A && B. I changed this the actual condition.
Differential Revision: https://reviews.llvm.org/D63538
llvm-svn: 365036