Summary:
The check emits a warning if std::move() is applied to a forwarding reference, i.e. an rvalue reference of a function template argument type.
If a developer is unaware of the special rules for template argument deduction on forwarding references, it will seem reasonable to apply std::move() to the forwarding reference, in the same way that this would be done for a "normal" rvalue reference.
This has a consequence that is usually unwanted and possibly surprising: If the function that takes the forwarding reference as its parameter is called with an lvalue, that lvalue will be moved from (and hence placed into an indeterminate state) even though no std::move() was applied to the lvalue at the callsite.
As a fix, the check will suggest replacing the std::move() with a std::forward().
This patch requires D23004 to be submitted before it.
Reviewers: sbenza, aaron.ballman
Subscribers: klimek, etienneb, alexfh, aaron.ballman, Prazek, Eugene.Zelenko, mgehre, cfe-commits
Projects: #clang-tools-extra
Differential Revision: https://reviews.llvm.org/D22220
llvm-svn: 280077
I've found this out the hard way; LLVM will not normally catch this
error (unless -verify-machineinstrs is passed), and under certain
very specific circumstances (such as register scavenger running
under pressure) this would result in an opaque crash in codegen.
llvm-svn: 280071
FreeBSD/mips script has non-wildcard filename specifications:
.text :
{
start.o(.text*)
Patch adds support for that, this is PR29115.
Differential revision: https://reviews.llvm.org/D23839
llvm-svn: 280069
Previously for extern keyword only names in quotes (exact match) was supported.
Patch adds support for wildcards, so next scripts can be handled properly:
LIBSAMPLE_1.0 {
global:
extern "C++" {
foo*;
};
};
Differential revision: https://reviews.llvm.org/D23794
llvm-svn: 280067
to CC1, which are translated to function attributes and can e.g. be mapped on
build attributes FP_exceptions and FP_denormal. Setting these build attributes
allows better selection of floating point libraries.
Differential Revision: https://reviews.llvm.org/D23840
llvm-svn: 280064
Old output was:
clang-rename: could not find symbol at tools/clang/tools/extra/test/clang-rename/ClassFindByName.cpp:1:1 (offset 0).
Reviewers: omtcyfz
Differential Revision: https://reviews.llvm.org/D24002
llvm-svn: 280062
The coverage reports contain the source or binary file paths. On Windows,
the file path might contain the seperators of both '/' and '\'. This patch
uses the native path in the coverage reports. For example, on Windows,
all '/' are converted to '\'.
Differential Revision: https://reviews.llvm.org/D23922
llvm-svn: 280061
only) for Expected<T> so that it can interoperate with MSVC's std::future
implementation.
MSVC 2013's std::future implementation requires the wrapped type to be default
constructible.
Hopefully this will fix the bot breakage in
http://lab.llvm.org:8011/builders/clang-x86-win2008-selfhost/builds/9937 .
llvm-svn: 280058
The former is simply wrong -- the code will either never be used or will
always be used, rather than being dependent upon whether it's built with
debug assertions enabled.
The macro DEBUG isn't ever set by the llvm build system. But, the macro
DEBUG(X) is defined (unconditionally) if you happen to include
llvm/Support/Debug.h.
The code in Value.h which was erroneously protected by the #ifdef DEBUG
didn't even compile -- you can't cast<> from an LLVMOpaqueValue
directly. Fortunately, it was never invoked, as Core.cpp included
Value.h before Debug.h.
The conditionalized code in AArch64CollectLOH.cpp was previously always
used, as it includes Debug.h.
llvm-svn: 280056
The PPC64 DWARF register-size table did not match the ABI specification (or
GCC, for that matter). Fix that, and add a regression test.
Fixes PR27931.
llvm-svn: 280053
behaviors, and add a callB (blacking call) primitive.
callB is a blocking call primitive for threaded code where the RPC responses are
being processed on a separate thread. (For single threaded code callST should
continue to be used instead).
No unit test yet: Last time I commited a threaded unit test it deadlocked on
one of the s390x builders. I'll try to re-enable that test first, and add a new
test if I can sort out the deadlock issue.
llvm-svn: 280051
Some of the mutex tests fail on machines with high load. This patch implements
the test directive "// FLAKY_TEST" which allows a test to be run 3 times
before it's considered a failure.
llvm-svn: 280050
Implement Bill's suggested fix for 32-bit targets for PR22711 (for the
alignment of each entry). As pointed out in the bug report, we could just force
the section alignment, since we only add pointer-sized things currently, but
this fix is somewhat more future-proof.
llvm-svn: 280049
I'm working on a lower-level intrusive list that can be used
stand-alone, and splitting the files up a bit will make the code easier
to organize. Explode the ilist headers in advance to improve blame
lists in the future.
- Move ilist_node_base from ilist_node.h to ilist_node_base.h.
- Move ilist_base from ilist.h to ilist_base.h.
- Move ilist_iterator from ilist.h to ilist_iterator.h.
- Move ilist_node_access from ilist.h to ilist_node.h to support
ilist_iterator.
- Update unit tests to #include smaller headers.
- Clang-format the moved things.
I noticed in transit that there is a simplify_type specialization for
ilist_iterator. Since there is no longer an implicit conversion from
ilist<T>::iterator to T*, this doesn't make sense (effectively it's a
form of implicit conversion). For now I've added a FIXME.
llvm-svn: 280047
The "long call" option forces the use of the indirect calling sequence for all
calls (even those that don't really need it). GCC provides this option; This is
helpful, under certain circumstances, for building very-large binaries, and
some other specialized use cases.
Fixes PR19098.
llvm-svn: 280040