Summary:
This patch adds semantic checking and building of the fall-through `co_return;` statement as well as the `p.set_exception(std::current_exception())` call for handling uncaught exceptions.
The fall-through statement is built and checked according to:
> [dcl.fct.def.coroutine]/4
> The unqualified-ids return_void and return_value are looked up in the scope of class P. If
> both are found, the program is ill-formed. If the unqualified-id return_void is found, flowing
> off the end of a coroutine is equivalent to a co_return with no operand. Otherwise, flowing off
> the end of a coroutine results in undefined behavior.
Similarly the `set_exception` call is only built when that unqualified-id is found in the scope of class P.
Additionally this patch adds fall-through warnings for non-void returning coroutines. Since it's surprising undefined behavior I thought it would be important to add the warning right away.
Reviewers: majnemer, GorNishanov, rsmith
Subscribers: mehdi_amini, cfe-commits
Differential Revision: https://reviews.llvm.org/D25349
llvm-svn: 285271
Revision r211132 was supposed to disable -Warc-repeated-use-of-weak for
Objective-C properties marked with the IBOutlet attribute. Those properties
are supposed to be weak but they are only accessed from the main thread
so there is no risk of asynchronous updates setting them to nil. That
combination makes -Warc-repeated-use-of-weak very noisy. The previous
change only handled one kind of access to weak IBOutlet properties.
Instead of trying to add checks for all the different kinds of property
accesses, this patch removes the previous special case check and adds a
check at the point where the diagnostic is reported. rdar://21366461
llvm-svn: 270665
Usually these parameters are used solely to initialize the field in the
initializer list, and there is no real shadowing confusion.
There is a new warning under -Wshadow called
-Wshadow-field-in-constructor-modified. It attempts to find
modifications of such constructor parameters that probably intended to
modify the field.
It has some false negatives, though, so there is another warning group,
-Wshadow-field-in-constructor, which always warns on this special case.
For users who just want the old behavior and don't care about these fine
grained groups, we have a new warning group called -Wshadow-all that
activates everything.
Fixes PR16088.
Reviewers: rsmith
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D18271
llvm-svn: 267957
exactly the same as clang's existing [[clang::fallthrough]] attribute, which
has been updated to have the same semantics. The one significant difference
is that [[fallthrough]] is ill-formed if it's not used immediately before a
switch label (even when -Wimplicit-fallthrough is disabled). To support that,
we now build a CFG of any function that uses a '[[fallthrough]];' statement
to check.
In passing, fix some bugs with our support for statement attributes -- in
particular, diagnose their use on declarations, rather than asserting.
llvm-svn: 262881
Previously, __weak was silently accepted and ignored in MRC mode.
That makes this a potentially source-breaking change that we have to
roll out cautiously. Accordingly, for the time being, actual support
for __weak references in MRC is experimental, and the compiler will
reject attempts to actually form such references. The intent is to
eventually enable the feature by default in all non-GC modes.
(It is, of course, incompatible with ObjC GC's interpretation of
__weak.)
If you like, you can enable this feature with
-Xclang -fobjc-weak
but like any -Xclang option, this option may be removed at any point,
e.g. if/when it is eventually enabled by default.
This patch also enables the use of the ARC __unsafe_unretained qualifier
in MRC. Unlike __weak, this is being enabled immediately. Since
variables are essentially __unsafe_unretained by default in MRC,
the only practical uses are (1) communication and (2) changing the
default behavior of by-value block capture.
As an implementation matter, this means that the ObjC ownership
qualifiers may appear in any ObjC language mode, and so this patch
removes a number of checks for getLangOpts().ObjCAutoRefCount
that were guarding the processing of these qualifiers. I don't
expect this to be a significant drain on performance; it may even
be faster to just check for these qualifiers directly on a type
(since it's probably in a register anyway) than to do N dependent
loads to grab the LangOptions.
rdar://9674298
llvm-svn: 251041
Now that -Winfinite-recursion no longer uses recursive calls to before path
analysis, several bits of the code can be improved. The main changes:
1) Early return when finding a path to the exit block without a recursive call
2) Moving the states vector into checkForRecursiveFunctionCall instead of
passing it in by reference
3) Change checkForRecursiveFunctionCall to return a bool when the warning
should be emitted.
4) Use the State vector instead of storing it in the Stack vector.
llvm-svn: 245666
In llvm commit r243581, a reverse range adapter was added which allows
us to change code such as
for (auto I = Fields.rbegin(), E = Fields.rend(); I != E; ++I) {
in to
for (const FieldDecl *I : llvm::reverse(Fields))
This commit changes a few of the places in clang which are eligible to use
this new adapter.
llvm-svn: 243663
Large CFGs cause `checkForFunctionCall()` to overflow its stack. Break
the recursion by manually managing the call stack instead.
Patch by Vedant Kumar!
llvm-svn: 243039
Split out `hasRecursiveCallInPath()` from `checkForFunctionCall()` to
flatten nesting and clarify the code. This also simplifies a follow-up
patch that refactors the other logic in `checkForFunctionCall()`.
Patch by Vedant Kumar!
llvm-svn: 243038
The patch is generated using this command:
$ tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
-checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
work/llvm/tools/clang
To reduce churn, not touching namespaces spanning less than 10 lines.
llvm-svn: 240270
Summary:
This patch is part of http://llvm-reviews.chandlerc.com/D2181.
In-class initializers are appended to the CFG when CFGBuilder::addInitializer is called.
Reviewers: jordan_rose, rsmith
Reviewed By: jordan_rose
Subscribers: cfe-commits, klimek
Differential Revision: http://reviews.llvm.org/D2370
llvm-svn: 238913
If the type isn't trivially moveable emplace can skip a potentially
expensive move. It also saves a couple of characters.
Call sites were found with the ASTMatcher + some semi-automated cleanup.
memberCallExpr(
argumentCountIs(1), callee(methodDecl(hasName("push_back"))),
on(hasType(recordDecl(has(namedDecl(hasName("emplace_back")))))),
hasArgument(0, bindTemporaryExpr(
hasType(recordDecl(hasNonTrivialDestructor())),
has(constructExpr()))),
unless(isInTemplateInstantiation()))
No functional change intended.
llvm-svn: 238601
These checks detect potential deadlocks caused by inconsistent lock
ordering. The checks are implemented under the -Wthread-safety-beta flag.
This patch also replaces calls to getAttrs() with calls to attrs() throughout
ThreadSafety.cpp, which fixes the earlier issue that cause assert failures.
llvm-svn: 228051
These checks detect potential deadlocks caused by inconsistent lock
ordering. The checks are implemented under the -Wthread-safety-beta flag.
llvm-svn: 227997
warns when a guarded variable is passed by reference as a function argument.
This is released as a separate warning flag, because it could potentially
break existing code that uses thread safety analysis.
llvm-svn: 218087
til::SExpr. This is a large patch, with many small changes to pretty printing
and expression lowering to make the new SExpr representation equivalent in
functionality to the old.
llvm-svn: 214089
The compilation pipeline doesn't actually need to know about the high-level
concept of diagnostic mappings, and hiding the final computed level presents
several simplifications and other potential benefits.
The only exceptions are opportunistic checks to see whether expensive code
paths can be avoided for diagnostics that are guaranteed to be ignored at a
certain SourceLocation.
This commit formalizes that invariant by introducing and using
DiagnosticsEngine::isIgnored() in place of individual level checks throughout
lex, parse and sema.
llvm-svn: 211005
which warns on compound conditionals that always evaluate to the same value.
For instance, (x > 5 && x < 3) will always be false since no value for x can
satisfy both conditions.
This patch also changes the CFG to use these tautological values for better
branch analysis. The test for -Wunreachable-code shows how this change catches
additional dead code.
Patch by Anders Rönnholm.
llvm-svn: 205665
Taking a hint from -Wparentheses, use an extra '()' as a sigil that
a dead condition is intentionally dead. For example:
if ((0)) { dead }
When this sigil is found, do not emit a dead code warning. When the
analysis sees:
if (0)
it suggests inserting '()' as a Fix-It.
llvm-svn: 205069
The exception is return statements that include control-flow,
which are clearly doing something "interesting".
99% of the cases I examined for -Wunreachable-code that fired
on return statements were not interesting enough to warrant
being in -Wunreachable-code by default. Thus the move to
include them in -Wunreachable-code-return.
This simplifies a bunch of logic, including removing the ad hoc
logic to look for std::string literals.
llvm-svn: 204307
Eric Fiselier