A return type is the declared or deduced part of the function type specified in
the declaration.
A result type is the (potentially adjusted) type of the value of an expression
that calls the function.
Rule of thumb:
* Declarations have return types and parameters.
* Expressions have result types and arguments.
llvm-svn: 200082
Previously, string literals were ignored in all logical expressions. This
reduces it to only ignore in logical and expressions.
assert(0 && "error"); // No warning
assert(0 || "error"); // Warn
Fixes PR17565
llvm-svn: 200056
This involved making CheckReturnStackAddr into a static function, which
is now called by a top-level return value checking routine called
CheckReturnValExpr.
llvm-svn: 199790
Fix a perennial source of confusion in the clang type system: Declarations and
function prototypes have parameters to which arguments are supplied, so calling
these 'arguments' was a stretch even in C mode, let alone C++ where default
arguments, templates and overloading make the distinction important to get
right.
Readability win across the board, especially in the casting, ADL and
overloading implementations which make a lot more sense at a glance now.
Will keep an eye on the builders and update dependent projects shortly.
No functional change.
llvm-svn: 199686
This allows the following syntax:
void baz(__attribute__((nonnull)) const char *str);
instead of:
void baz(const char *str) __attribute__((nonnull(1)));
This also extends to Objective-C methods.
The checking logic in Sema is not as clean as I would like. Effectively
now we need to check both the FunctionDecl/ObjCMethodDecl and the parameters,
so the point of truth is spread in two places, but the logic isn't that
cumbersome.
Implements <rdar://problem/14691443>.
llvm-svn: 199467
The ABI requires the destructor to be invoked in the callee, but the
standard does not require access checks here so we avoid doing direct
access checks on the destructor.
If we end up needing to define an implicit destructor, we don't skip
access checks for the base class, etc. Those checks are effectively part
of generating the destructor definition, and aren't affected by which TU
the check is performed in.
Differential Revision: http://llvm-reviews.chandlerc.com/D2409
llvm-svn: 199120
encodes the canonical rules for LLVM's style. I noticed this had drifted
quite a bit when cleaning up LLVM, so wanted to clean up Clang as well.
llvm-svn: 198686
Thisadds a new warning that warns on code like this:
if (memcmp(a, b, sizeof(a) != 0))
The warning looks like:
test4.cc:5:30: warning: size argument in 'memcmp' call is a comparison [-Wmemsize-comparison]
if (memcmp(a, b, sizeof(a) != 0))
~~~~~~~~~~^~~~
test4.cc:5:7: note: did you mean to compare the result of 'memcmp' instead?
if (memcmp(a, b, sizeof(a) != 0))
^ ~
)
test4.cc:5:20: note: explicitly cast the argument to size_t to silence this warning
if (memcmp(a, b, sizeof(a) != 0))
^
(size_t)( )
1 warning generated.
This found 2 bugs in chromium and has 0 false positives on both chromium and
llvm.
The idea of triggering this warning on a binop in the size argument is due to
rnk.
llvm-svn: 198063
Summary:
MSVC destroys arguments in the callee from left to right. Because C++
objects have to be destroyed in the reverse order of construction, Clang
has to construct arguments from right to left and destroy arguments from
left to right.
This patch fixes the ordering by reversing the order of evaluation of
all call arguments under the MS C++ ABI.
Fixes PR18035.
Reviewers: rsmith
Differential Revision: http://llvm-reviews.chandlerc.com/D2275
llvm-svn: 196402
The AST was constructed so that this builtin returned the default BoolTy and
since I'd opted for custom SemaChecking, I should have set it properly at that
point.
This caused an assertion failure when the types didn't match up with what we
generated. This makes it return an IntTy, which is as good as anything.
llvm-svn: 193606
_Bool in C, if the macro is defined. Also teach FixItUtils to look at whether
the macro was defined at the source location for which it is creating a fixit,
rather than looking at whether it's defined *now*. This is especially relevant
for analysis-based warnings which are delayed until end of TU.
llvm-svn: 191057
LLVM supports applying conversion instructions to vectors of the same number of
elements (fptrunc, fptosi, etc.) but there had been no way for a Clang user to
cause such instructions to be generated when using builtin vector types.
C-style casting on vectors is already defined in terms of bitcasts, and so
cannot be used for these conversions as well (without leading to a very
confusing set of semantics). As a result, this adds a __builtin_convertvector
intrinsic (patterned after the OpenCL __builtin_astype intrinsic). This is
intended to aid the creation of vector intrinsic headers that create generic IR
instead of target-dependent intrinsics (in other words, this is a generic
_mm_cvtepi32_ps). As noted in the documentation, the action of
__builtin_convertvector is defined in terms of the action of a C-style cast on
each vector element.
llvm-svn: 190915
I changed the diagnostic printing code because it's probably better
to cut off a digit from DBL_MAX than to print something like
1.300000001 when the user wrote 1.3.
llvm-svn: 189625
Basically, isInMainFile considers line markers, and isWrittenInMainFile
doesn't. Distinguishing between the two is useful when dealing with
files which are preprocessed files or rewritten with -frewrite-includes
(so we don't, for example, print useless warnings).
llvm-svn: 188968
function: it can't be 'void' and it can't be an initializer list. We give a
hard error for these rather than treating them as undefined behavior (we can
and probably should do the same for non-POD types in C++11, but as of this
change we don't).
Slightly rework the checking of variadic arguments in a function with a format
attribute to ensure that certain kinds of format string problem (non-literal
string, too many/too few arguments, ...) don't suppress this error.
llvm-svn: 187735
Patch by Ana Pazos
- Completed implementation of instruction formats:
AdvSIMD three same
AdvSIMD modified immediate
AdvSIMD scalar pairwise
- Completed implementation of instruction classes
(some of the instructions in these classes
belong to yet unfinished instruction formats):
Vector Arithmetic
Vector Immediate
Vector Pairwise Arithmetic
- Initial implementation of instruction formats:
AdvSIMD scalar two-reg misc
AdvSIMD scalar three same
- Intial implementation of instruction class:
Scalar Arithmetic
- Initial clang changes to support arm v8 intrinsics.
Note: no clang changes for scalar intrinsics function name mangling yet.
- Comprehensive test cases for added instructions
To verify auto codegen, encoding, decoding, diagnosis, intrinsics.
llvm-svn: 187568
Previously a diagnostic was issued, but the code went ahead and built the ShuffleVectorExpr. While I'm here also simplify a couple lines by wrapping the return ExprError around the Diag calls.
llvm-svn: 187344
This adds three overloaded intrinsics to Clang:
T __builtin_arm_ldrex(const volatile T *addr)
int __builtin_arm_strex(T val, volatile T *addr)
void __builtin_arm_clrex()
The intent is that these do what users would expect when given most sensible
types. Currently, "sensible" translates to ints, floats and pointers.
llvm-svn: 186394
& operator (ignoring any overloaded operator& for the type). The purpose of
this builtin is for use in std::addressof, to allow it to be made constexpr;
the existing implementation technique (reinterpret_cast to some reference type,
take address, reinterpert_cast back) does not permit this because
reinterpret_cast between reference types is not permitted in a constant
expression in C++11 onwards.
llvm-svn: 186053
Use UsualArithmeticConversions unconditionally in analysis of
comparisons and conditional operators: the method performs
the usual arithmetic conversions if both sides are arithmetic, and
usual unary conversions if they are not. This is just a cleanup
for conditional operators; for comparisons, it fixes the issue that
we would try to check isArithmetic() on an atomic type.
Also, fix GetExprRange() in SemaChecking.cpp so it deals with variables
of atomic type correctly.
Fixes PR15537.
llvm-svn: 185857
before the value computation of the result. In C, this is implied by there being
a sequence point after their evaluation, and in C++, it's implied by the
side-effects being sequenced before the expressions and statements in the
function body.
llvm-svn: 185282
side-effect is not sequenced before its value computation. Also fix a
mishandling of ?: expressions where the condition is constant that was
exposed by the tests for this.
llvm-svn: 185035
Itanium destroys them in the caller at the end of the full expression,
but MSVC destroys them in the callee. This is further complicated by
the need to emit EH-only destructor cleanups in the caller.
This should help clang compile MSVC's debug iterators more correctly.
There is still an outstanding issue in PR5064 of a memcpy emitted by the
LLVM backend, which is not correct for C++ records.
Fixes PR16226.
Reviewers: rjmccall
Differential Revision: http://llvm-reviews.chandlerc.com/D929
llvm-svn: 184543
operations in the case where evaluating a subexpression fails. No functionality
change, but test/Sema/many-logical-ops.c gets ~100x faster with this change.
llvm-svn: 184489
In some cases, clang applies the C++ rules for computing the range of a
value when said value is an enum.
Instead, apply C semantics when in C mode.
llvm-svn: 183084
- References to ObjC bit-field ivars are bit-field lvalues;
fixes rdar://13794269, which got me started down this.
- Introduce Expr::refersToBitField, switch a couple users to
it where semantically important, and comment the difference
between this and the existing API.
- Discourage Expr::getBitField by making it a bit longer and
less general-sounding.
- Lock down on const_casts of bit-field gl-values until we
hear back from the committee as to whether they're allowed.
llvm-svn: 181252
in the parameter of a function definition. Currently,
it crashes in irgen if it is on other than the 1st dimension.
// rdar://13705391
llvm-svn: 180732
likely be implicitly truncated:
* All forms of Bitwise-and, bitwise-or, and integer multiplication.
* The assignment form of integer addition, subtraction, and exclusive-or
* The RHS of the comma operator
* The LHS of left shifts.
llvm-svn: 178273
The TypeLoc hierarchy used the llvm::cast machinery to perform undefined
behavior by casting pointers/references to TypeLoc objects to derived types
and then using the derived copy constructors (or even returning pointers to
derived types that actually point to the original TypeLoc object).
Some context is in this thread:
http://lists.cs.uiuc.edu/pipermail/llvmdev/2012-December/056804.html
Though it's spread over a few months which can be hard to read in the mail
archive.
llvm-svn: 175462
argument to be memset, check for its type to be complete
before calling Context.getTypeSize(PointeeTy) to prevent
crash. // rdar://13081751.
llvm-svn: 173872
unsequenced operations in the RHS. We don't compare the RHS with the rest of
the expression yet; such checks will need care to avoid diagnosing unsequenced
operations which are both in conditionally-evaluated subexpressions which
actually can't occur together, such as in '(b && ++x) + (!b && ++x)'.
llvm-svn: 172760
expressions which have undefined behavior due to multiple unsequenced
modifications or an unsequenced modification and use of a variable.
llvm-svn: 172690
Along the way, fix a bug in CheckLiteralKind(), previously in diagnoseObjCLiteralComparison, where we didn't ignore parentheses
in boxed expressions for purpose of classification.
In other words, both @42 and @(42) should be classified as numeric
literals.
llvm-svn: 170931
This is just a minor bit of refactoring, but it is nice cleanup for
the subsequent patch that adds warning support for assigning literals
to weak variables.
llvm-svn: 170863
For most cases where a conversion specifier doesn't match an argument,
we usually guess that the conversion specifier is wrong. However, if
the argument is an integer type and the specifier is %C, it's likely
the user really did mean to print the integer as a character.
(This is more common than %c because there is no way to specify a unichar
literal -- you have to write an integer literal, such as '0x2603',
and then cast it to unichar.)
This does not change the behavior of %S, since there are fewer cases
where printing a literal Unicode *string* is necessary, but this could
easily be changed in the future.
<rdar://problem/11982013>
llvm-svn: 169400
The type of a character literal is 'int' in C, but if the user writes a
character /as/ a literal, we should assume they meant it to be a
character and not a numeric value, and thus offer %c as a correction
rather than %d.
There's a special case for multi-character literals (like 'MooV'), which
have implementation-defined value and usually cannot be printed with %c.
These still use %d as the suggestion.
In C++, the type of a character literal is 'char', and so this problem
doesn't exist.
<rdar://problem/12282316>
llvm-svn: 169398
uncovered.
This required manually correcting all of the incorrect main-module
headers I could find, and running the new llvm/utils/sort_includes.py
script over the files.
I also manually added quite a few missing headers that were uncovered by
shuffling the order or moving headers up to be main-module-headers.
llvm-svn: 169237
width of an enum with negative values in IntRange. Include a test for
-Wtautological-constant-out-of-range-compare where this had manifested.
llvm-svn: 168126
type conversion between integers. This allows the warning to be more accurate.
Also, turned the warning off in an analyzer test. The relavent test cases
are covered by the tests in Sema.
llvm-svn: 167992
Also applies to -Wnonnull, -Wtype-safety, and -Wnon-pod-varargs.
All of these can be better checked at instantiation time.
This change does not actually affect regular CallExpr function calls,
since the checks there only happen after overload resolution.
However, it will affect Objective-C method calls.
<rdar://problem/12373934>
llvm-svn: 164984
Like properties, loading from a weak ivar twice in the same function can
give you inconsistent results if the object is deallocated between the
two loads. It is safer to assign to a strong local variable and use that.
Second half of <rdar://problem/12280249>.
llvm-svn: 164855
Retain cycles happen in the case where a block is persisted past its
life on the stack, and the way that occurs is by copying the block.
We should thus look through any explicit copies we see.
Note that Block_copy is actually a type-safe wrapper for _Block_copy,
which does all the real work.
<rdar://problem/12219663>
llvm-svn: 164039
Specifically, this should warn:
__block block_t a = ^{ a(); };
Furthermore, this case which previously warned now does not, since the value
of 'b' is captured before the assignment occurs:
block_t b; // not __block
b = ^{ b(); };
(This will of course warn under -Wuninitialized, as before.)
<rdar://problem/11015883>
llvm-svn: 163962
These types are defined differently on 32-bit and 64-bit platforms, and
trying to offer a fixit for one platform would only mess up the format
string for the other. The Apple-recommended solution is to cast to a type
that is known to be large enough and always use that to print the value.
This should only have an impact on compile time if the format string is
incorrect; in cases where the format string matches the definition on the
current platform, no warning will be emitted.
<rdar://problem/9135072&12164284>
llvm-svn: 163266
(__builtin_* etc.) so that it isn't possible to take their address.
Specifically, introduce a new type to represent a reference to a builtin
function, and a new cast kind to convert it to a function pointer in the
operand of a call. Fixes PR13195.
llvm-svn: 162962
This warns in two specific situations:
1) For potentially swapped function arguments, e.g.
void foo(bool, float);
foo(1.7, false);
2) Misplaced brackets around function call arguments, e.g.
bool InRange = fabs(a - b < delta);
Where the last argument in a function call is implicitly converted
from bool to float, and the function returns a float which gets
implicitly converted to bool.
Patch by Andreas Eckleder!
llvm-svn: 162763
function arguments and arguments for variadic functions are of a particular
type which is determined by some other argument to the same function call.
Usecases include:
* MPI library implementations, where these attributes enable checking that
buffer type matches the passed MPI_Datatype;
* for HDF5 library there is a similar usecase as MPI;
* checking types of variadic functions' arguments for functions like
fcntl() and ioctl().
llvm-svn: 162067
and remove ASTContext reference (which was frequently bound to a dereferenced
null pointer) from the recursive lump of printPretty functions. In so doing,
fix (at least) one case where we intended to use the 'dump' mode, but that
failed because a null ASTContext reference had been passed in.
llvm-svn: 162011
tablegen code, found by -fcatch-undefined-behavior. I would appreciate if
someone more familiar with the NEON code could point me in the direction of how
to write a test for this. We appear to have essentially no test coverage
whatsoever for these builtins.
llvm-svn: 161827
This is useful for example for %n in printf, which expects
a pointer to int with the same logic for checking as %d
would have in scanf.
llvm-svn: 161407
The one caller that's surrounded by nearby code manipulating the underlying
evaluation context list is left unmodified for readability.
Review by Sean Silva and Richard Smith.
llvm-svn: 161355
While '%n' can be used for evil in an attacker-controlled format string, there
isn't any acute danger in using it in a literal format string with an argument
of the appropriate type.
llvm-svn: 160984
While we still want to consider this a hard error (non-POD variadic args are
normally a DefaultError warning), delaying the diagnostic allows us to give
better error messages, which also match the usual non-POD errors more closely.
In addition, this change improves the diagnostic messages for format string
argument type mismatches by passing down the type of the callee, so we can
say "variadic method" or "variadic function" appropriately.
<rdar://problem/11825593>
llvm-svn: 160517
Previously, we would ask for the SourceLocation of an argument even if
it were NULL (i.e. if Sema resulted in an ExprError trying to build it).
<rdar://problem/11890818>
llvm-svn: 160515
resulted in it being reverted. A test for that bug was added in r158950.
Original comment:
If an object (such as a std::string) with an appropriate c_str() member function
is passed to a variadic function in a position where a format string indicates
that c_str()'s return type is desired, provide a note suggesting that the user
may have intended to call the c_str() member.
Factor the non-POD-vararg checking out of DefaultVariadicArgumentPromotion and
move it to SemaChecking in order to facilitate this. Factor the call checking
out of function call checking and block call checking, and extend it to cover
constructor calls too.
Patch by Sam Panzer!
llvm-svn: 159159
Revert "If an object (such as a std::string) with an appropriate c_str() member function"
This reverts commit 7d96f6106bfbd85b1af06f34fdbf2834aad0e47e.
llvm-svn: 158949
This now correctly covers, I believe, all the pointer types:
* 'any' pointers (both function and data normal pointers and ObjC object pointers)
* member pointers (both function and data)
* block pointers
llvm-svn: 158931
is passed to a variadic function in a position where a format string indicates
that c_str()'s return type is desired, provide a note suggesting that the user
may have intended to call the c_str() member.
Factor the non-POD-vararg checking out of DefaultVariadicArgumentPromotion and
move it to SemaChecking in order to facilitate this. Factor the call checking
out of function call checking and block call checking, and extend it to cover
constructor calls too.
Patch by Sam Panzer!
llvm-svn: 158887
Within the guts of CheckFormatHandler, the IsObjCLiteral flag was being used in
two ways: to see if null bytes were allowed, and to see if the '%@' specifier
is allowed.* The former usage has been changed to an explicit test and the
latter pushed down to CheckPrintfHandler and renamed ObjCContext, since it
applies to CFStrings as well.
* This also changes how wide chars are interpreted; in OS X Foundation, the
wide character type is 'unichar', a typedef for short, rather than wchar_t.
llvm-svn: 157968
about argument type mismatch.
This gives a nicer diagnostic in cases like
printf(fmt,
i);
where previously the snippet just pointed at 'fmt' (with a note at the
definition of fmt).
It's a wash for cases like
printf("%f",
i);
where previously we snippeted the offending portion of the format string,
but didn't indicate which argument was at fault.
llvm-svn: 156968
This fixes the included test case & was reported by Nico Weber.
It's a little bit nasty using the difference in the conversion context, but
seems to me like a not unreasonable solution. I did have to fix up the
conversion context for conditional operators (it seems correct to me to include
the context for which we're actually doing the comparison - across all the
nested conditionals, rather than the innermost conditional which might not
actually have the problematic implicit conversion at all) and template default
arguments (this is a bit of a hack, since we don't have the source location of
the '=' anymore, so I just used the start of the parameter - open to
suggestions there)
llvm-svn: 156861
Moves the bool bail-out down a little in SemaChecking - so now
-Wnull-conversion and -Wliteral-conversion can fire when the target type is
bool.
Also improve the wording/details in the -Wliteral-conversion warning to match
the -Wconstant-conversion.
llvm-svn: 156826
getTypeSourceInfo() without checking for NULL.
FieldDecls may have NULL TypeSourceInfo, and in
fact some FieldDecls generated by Clang -- and
all FieldDecls generated by LLDB -- have no
TypeSourceInfo.
This patch makes IsTailPaddedMemberArray check
for NULL.
llvm-svn: 156186
off PartialDiagnostic. PartialDiagnostic is rather heavyweight for
something that is in the critical path and is rarely used. So, switch
over to an abstract-class-based callback mechanism that delays most of
the work until a diagnostic is actually produced. Good for ~11k code
size reduction in the compiler and 1% speedup in -fsyntax-only on the
code in <rdar://problem/11004361>.
llvm-svn: 156176
Teach ASTContext about WIntType, and have it taken from TargetInfo like WCharType. Should fix test/Sema/format-strings.c for ARM, with the exception of one subtest which will fail if wint_t and wchar_t are the same size and wint_t is signed, wchar_t is unsigned.
There'll be a followup commit to fix that.
Reviewed by Chandler and Hans at http://llvm.org/reviews/r/8
llvm-svn: 156165
Some of the NSAssert macros in OS X 10.7 are implemented in a way that
adds extra arguments that trigger the -Wformat-extra-args warning.
Earlier versions of clang failed to detect those -Wformat issues, but now
that clang is reporting those problems, we need to quiet them since there's
nothing to be done to fix them. <rdar://problem/11317765>
I don't know how to write a testcase for this. Suggestions welcome.
Patch by Ted Kremenek!
llvm-svn: 156092
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
i32 __builtin_annotation(i32, string);
Applying it to i64 (e.g., long long) generates the following IR.
trunc i64 {{.*}} to i32
call i32 @llvm.annotation.i32
zext i32 {{.*}} to i64
The redundant truncation and extension make the result difficult to use.
This patch makes __builtin_annotation() generic.
type __builtin_annotation(type, string);
For the i64 example, it simplifies the generated IR to:
call i64 @llvm.annotation.i64
Patch by Xi Wang!
llvm-svn: 155764
The codepath already only works for source bits > target bits, it's just that
it was testing for the source expr bits to be exactly 64. This meant simple
cases (int i = x_long / 2) were missed & ended up under the general
-Wconversion warning, which a user might not have enabled.
llvm-svn: 154626
This is not quite sufficient for libstdc++'s <atomic>: we still need
__atomic_test_and_set and __atomic_clear, and may need a more complete
__atomic_is_lock_free implementation.
We are also missing an implementation of __atomic_always_lock_free,
__atomic_nand_fetch, and __atomic_fetch_nand, but those aren't needed
for libstdc++.
llvm-svn: 154579
<stdatomic.h> header.
In passing, fix LanguageExtensions to note that C11 and C++11 are no longer
"upcoming standards" but are now actually standardized.
llvm-svn: 154513
For "int i = NULL;" we would produce:
null.cpp:5:11: warning: implicit conversion of NULL constant to integer [-Wconversion]
int i = NULL;
~ ^~~~
null.cpp:1:14: note: expanded from macro 'NULL'
\#define NULL __null
^~~~~~
But we really shouldn't trace that macro expansion back into the header, yet we
still want macro back traces for code like this:
\#define FOO NULL
int i = FOO;
or
\#define FOO int i = NULL;
FOO
While providing appropriate tagging at different levels of the expansion, etc.
The included test case exercises these cases & does some basic validation (to
ensure we don't have macro expansion notes where we shouldn't, and do where we
should) - but doesn't go as far as to validate the source location/ranges
used in those notes and warnings.
llvm-svn: 152940
track whether the referenced declaration comes from an enclosing
local context. I'm amenable to suggestions about the exact meaning
of this bit.
llvm-svn: 152491
This renames the -Wformat-non-standard flag to -Wformat-non-iso,
rewords the current warnings a bit (pointing out that a format string
is not supported by ISO C rather than being "non standard"),
and adds a warning about positional arguments.
llvm-svn: 152403
Richard Smith