There is a clangd crash at `__memcmp_avx2_movbe`. Short problem description is below.
The method `HeaderIncludes::addExistingInclude` stores `Include` objects by reference at 2 places: `ExistingIncludes` (primary storage) and `IncludesByPriority` (pointer to the object's location at ExistingIncludes). `ExistingIncludes` is a map where value is a `SmallVector`. A new element is inserted by `push_back`. The operation might do resize. As result pointers stored at `IncludesByPriority` might become invalid.
Typical stack trace
```
frame #0: 0x00007f11460dcd94 libc.so.6`__memcmp_avx2_movbe + 308
frame #1: 0x00000000004782b8 clangd`llvm::StringRef::compareMemory(Lhs="
\"t2.h\"", Rhs="", Length=6) at StringRef.h:76:22
frame #2: 0x0000000000701253 clangd`llvm::StringRef::compare(this=0x0000
7f10de7d8610, RHS=(Data = "", Length = 7166742329480737377)) const at String
Ref.h:206:34
* frame #3: 0x00000000007603ab clangd`llvm::operator<(llvm::StringRef, llv
m::StringRef)(LHS=(Data = "\"t2.h\"", Length = 6), RHS=(Data = "", Length =
7166742329480737377)) at StringRef.h:907:23
frame #4: 0x0000000002d0ad9f clangd`clang::tooling::HeaderIncludes::inse
rt(this=0x00007f10de7fb1a0, IncludeName=(Data = "t2.h\"", Length = 4), IsAng
led=false) const at HeaderIncludes.cpp:365:22
frame #5: 0x00000000012ebfdd clangd`clang::clangd::IncludeInserter::inse
rt(this=0x00007f10de7fb148, VerbatimHeader=(Data = "\"t2.h\"", Length = 6))
const at Headers.cpp:262:70
```
A unit test test for the crash was created (`HeaderIncludesTest.RepeatedIncludes`). The proposed solution is to use std::list instead of llvm::SmallVector
Test Plan
```
./tools/clang/unittests/Tooling/ToolingTests --gtest_filter=HeaderIncludesTest.RepeatedIncludes
```
Reviewed By: sammccall
Differential Revision: https://reviews.llvm.org/D118755
Motivating use case is ".cu.cc" extensions used in some bazel projects.
Alternative is to work around this with IncludeIsMainRegex in styles.
I proposed this approach because it seems like a better default.
Differential Revision: https://reviews.llvm.org/D86597
This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.
This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.
This doesn't actually modify StringRef yet, I'll do that in a follow-up.
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
Summary:
clangToolingCore is linked into almost everything (incl. clang), but
not few tools need #include manipulation at this point. So pull this into a
separate library in Tooling.
Reviewers: ilya-biryukov
Subscribers: klimek, mgorny, cfe-commits, thakis
Differential Revision: https://reviews.llvm.org/D47068
llvm-svn: 332720
Ivan Murashko