This attribute is used to prevent tail-call optimizations to the marked
function. For example, in the following piece of code, foo1 will not be
tail-call optimized:
int __attribute__((not_tail_called)) foo1(int);
int foo2(int a) {
return foo1(a); // Tail-call optimization is not performed.
}
The attribute has effect only on statically bound calls. It has no
effect on indirect calls. Also, virtual functions and objective-c
methods cannot be marked as 'not_tail_called'.
rdar://problem/22667622
Differential Revision: http://reviews.llvm.org/D12922
llvm-svn: 252369
This checker looks for unsafe constructs in vforked process:
function calls (excluding whitelist), memory write and returns.
This was originally motivated by a vfork-related bug in xtables package.
Patch by Yury Gribov.
Differential revision: http://reviews.llvm.org/D14014
llvm-svn: 252285
Summary:
This is needed to handle per-project configurations when adding extra
arguments in clang-tidy for example.
Reviewers: klimek, djasper
Subscribers: djasper, cfe-commits, klimek
Differential Revision: http://reviews.llvm.org/D14191
llvm-svn: 252134
we can't load that file due to a configuration mismatch, and implicit module
building is disabled, and the user turns off the error-by-default warning for
that situation, then fall back to textual inclusion for the module rather than
giving an error if any of its headers are included.
llvm-svn: 252114
internal linkage entities in different modules from r250884 to apply to all
names, not just function names.
This is really awkward: we don't want to merge internal-linkage symbols from
separate modules, because they might not actually be defining the same entity.
But we don't want to reject programs that use such an ambiguous symbol if those
internal-linkage symbols are in fact equivalent. For now, we're resolving the
ambiguity by picking one of the equivalent definitions as an extension.
llvm-svn: 252063
This new builtin template allows for incredibly fast instantiations of
templates like std::integer_sequence.
Performance numbers follow:
My work station has 64 GB of ram + 20 Xeon Cores at 2.8 GHz.
__make_integer_seq<std::integer_sequence, int, 90000> takes 0.25
seconds.
std::make_integer_sequence<int, 90000> takes unbound time, it is still
running. Clang is consuming gigabytes of memory.
Differential Revision: http://reviews.llvm.org/D13786
llvm-svn: 252036
Introduce the notion of a module file extension, which introduces
additional information into a module file at the time it is built that
can then be queried when the module file is read. Module file
extensions are identified by a block name (which must be unique to the
extension) and can write any bitstream records into their own
extension block within the module file. When a module file is loaded,
any extension blocks are matched up with module file extension
readers, that are per-module-file and are given access to the input
bitstream.
Note that module file extensions can only be introduced by
programmatic clients that have access to the CompilerInvocation. There
is only one such extension at the moment, which is used for testing
the module file extension harness. As a future direction, one could
imagine allowing the plugin mechanism to introduce new module file
extensions.
llvm-svn: 251955
Now that the properties created within Objective-C class extensions go
into the extension themselves, we don't need any of the extra
complexity here.
llvm-svn: 251949
A 'readonly' Objective-C property declared in the primary class can
effectively be shadowed by a 'readwrite' property declared within an
extension of that class, so long as the types and attributes of the
two property declarations are compatible.
Previously, this functionality was implemented by back-patching the
original 'readonly' property to make it 'readwrite', destroying source
information and causing some hideously redundant, incorrect
code. Simplify the implementation to express how this should actually
be modeled: as a separate property declaration in the extension that
shadows (via the name lookup rules) the declaration in the primary
class. While here, correct some broken Fix-Its, eliminate a pile of
redundant code, clean up the ARC migrator's handling of properties
declared in extensions, and fix debug info's naming of methods that
come from categories.
A wonderous side effect of doing this write is that it eliminates the
"AddedObjCPropertyInClassExtension" method from the AST mutation
listener, which in turn eliminates the last place where we rewrite
entire declarations in a chained PCH file or a module file. This
change (which fixes rdar://problem/18475765) will allow us to
eliminate the rewritten-decls logic from the serialization library,
and fixes a crash (rdar://problem/23247794) illustrated by the
test/PCH/chain-categories.m example.
llvm-svn: 251874
Summary:
The hasBase and hasIndex don't tell anything about the position of the
base and the index in the code, so we need hasLHS and hasRHS in some cases.
Reviewers: klimek
Subscribers: klimek, cfe-commits
Differential Revision: http://reviews.llvm.org/D14212
llvm-svn: 251842
We permit implicit conversion from pointer-to-function to
pointer-to-object when -fms-extensions is specified. This is rather
unfortunate, move this into -fms-compatibility and only permit it within
system headers unless -Wno-error=microsoft-cast is specified.
llvm-svn: 251738
This sets the mostly expected Darwin default ABI options for these two
platforms. Active changes from these defaults for watchOS are in a later patch.
llvm-svn: 251708
This patch should add support for almost all command-line options and
driver tinkering necessary to produce a correct "clang -cc1"
invocation for watchOS and tvOS.
llvm-svn: 251706
Summary: This matchers are going to be used in modernize-use-default, but are generic enough to be placed in ASTMatchers.h.
Reviewers: klimek
Subscribers: alexfh, cfe-commits, klimek
Differential Revision: http://reviews.llvm.org/D14152
llvm-svn: 251693
Summary:
Dear All,
We have been looking at the following problem, where any code after the constant bound loop is not analyzed because of the limit on how many times the same block is visited, as described in bugzillas #7638 and #23438. This problem is of interest to us because we have identified significant bugs that the checkers are not locating. We have been discussing a solution involving ranges as a longer term project, but I would like to propose a patch to improve the current implementation.
Example issue:
```
for (int i = 0; i < 1000; ++i) {...something...}
int *p = 0;
*p = 0xDEADBEEF;
```
The proposal is to go through the first and last iterations of the loop. The patch creates an exploded node for the approximate last iteration of constant bound loops, before the max loop limit / block visit limit is reached. It does this by identifying the variable in the loop condition and finding the value which is “one away” from the loop being false. For example, if the condition is (x < 10), then an exploded node is created where the value of x is 9. Evaluating the loop body with x = 9 will then result in the analysis continuing after the loop, providing x is incremented.
The patch passes all the tests, with some modifications to coverage.c, in order to make the ‘function_which_gives_up’ continue to give up, since the changes allowed the analysis to progress past the loop.
This patch does introduce possible false positives, as a result of not knowing the state of variables which might be modified in the loop. I believe that, as a user, I would rather have false positives after loops than do no analysis at all. I understand this may not be the common opinion and am interested in hearing your views. There are also issues regarding break statements, which are not considered. A more advanced implementation of this approach might be able to consider other conditions in the loop, which would allow paths leading to breaks to be analyzed.
Lastly, I have performed a study on large code bases and I think there is little benefit in having “max-loop” default to 4 with the patch. For variable bound loops this tends to result in duplicated analysis after the loop, and it makes little difference to any constant bound loop which will do more than a few iterations. It might be beneficial to lower the default to 2, especially for the shallow analysis setting.
Please let me know your opinions on this approach to processing constant bound loops and the patch itself.
Regards,
Sean Eveson
SN Systems - Sony Computer Entertainment Group
Reviewers: jordan_rose, krememek, xazax.hun, zaks.anna, dcoughlin
Subscribers: krememek, xazax.hun, cfe-commits
Differential Revision: http://reviews.llvm.org/D12358
llvm-svn: 251621
GCC has a warning called -Wdouble-promotion, which warns you when
an implicit conversion increases the width of a floating point type.
This is useful when writing code for architectures that can perform
hardware FP ops on floats, but must fall back to software emulation for
larger types (i.e. double, long double).
This fixes PR15109 <https://llvm.org/bugs/show_bug.cgi?id=15109>.
Thanks to Carl Norum for the patch!
llvm-svn: 251588
Fake arguments are automatically handled for serialization, cloning,
and other representational tasks, but aren't included in pretty-printing
or parsing (should we eventually ever automate that).
This is chiefly useful for attributes that can be written by the
user, but which are also frequently synthesized by the compiler,
and which we'd like to remember details of the synthesis for.
As a simple example, use this to narrow the cases in which we were
generating a specialized note for implicitly unavailable declarations.
llvm-svn: 251469
The analyzer assumes that system functions will not free memory or modify the
arguments in other ways, so we assume that arguments do not escape when
those are called. However, this may lead to false positive leak errors. For
example, in code like this where the pointers added to the rb_tree are freed
later on:
struct alarm_event *e = calloc(1, sizeof(*e));
<snip>
rb_tree_insert_node(&alarm_tree, e);
Add a heuristic to assume that calls to system functions taking void*
arguments allow for pointer escape.
llvm-svn: 251449
Linking options for particular file depend on the option that specifies the file.
Currently there are two:
* -mlink-bitcode-file links in complete content of the specified file.
* -mlink-cuda-bitcode links in only the symbols needed by current TU.
Linked symbols are internalized. This bitcode linking mode is used to
link device-specific bitcode provided by CUDA.
Files are linked in order they are specified on command line.
-mlink-cuda-bitcode replaces -fcuda-uses-libdevice flag.
Differential Revision: http://reviews.llvm.org/D13913
llvm-svn: 251427
Summary:
If this option is set, clang-format will always insert a line wrap, e.g.
before the first parameter of a function call unless all parameters fit
on the same line. This obviates the need to make a decision on the
alignment itself.
Use this style for Google's JavaScript style and add some minor tweaks
to correctly handle nested blocks etc. with it. Don't use this option
for for/while loops.
Reviewers: klimek
Subscribers: klimek, cfe-commits
Differential Revision: http://reviews.llvm.org/D14104
llvm-svn: 251405
only one of a group of possibilities.
This changes the syntax in the builtin files to represent:
, as the and operator
| as the or operator
The former syntax matches how the backend tablegen files represent
multiple subtarget features being required.
Updated the builtin and intrinsic headers accordingly for the new
syntax.
llvm-svn: 251388