Commit Graph

10 Commits

Author SHA1 Message Date
Louis Dionne 564628014c [libc++] Introduce an indirection to create threads in the test suite
We create threads using std::thread in various places in the test suite.
However, the usual std::thread constructor may not work on all platforms,
e.g. on platforms where passing a stack size is required to create a thread.

This commit introduces a simple indirection that makes it easier to tweak
how threads are created inside the test suite on various platforms. Note
that tests that are purposefully calling std::thread's constructor directly
(e.g. because that is what they're testing) were not modified.
2020-11-27 11:54:19 -05:00
JF Bastien 2df59c5068 Support tests in freestanding
Summary:
Freestanding is *weird*. The standard allows it to differ in a bunch of odd
manners from regular C++, and the committee would like to improve that
situation. I'd like to make libc++ behave better with what freestanding should
be, so that it can be a tool we use in improving the standard. To do that we
need to try stuff out, both with "freestanding the language mode" and
"freestanding the library subset".

Let's start with the super basic: run the libc++ tests in freestanding, using
clang as the compiler, and see what works. The easiest hack to do this:

In utils/libcxx/test/config.py add:

  self.cxx.compile_flags += ['-ffreestanding']

Run the tests and they all fail.

Why? Because in freestanding `main` isn't special. This "not special" property
has two effects: main doesn't get mangled, and main isn't allowed to omit its
`return` statement. The first means main gets mangled and the linker can't
create a valid executable for us to test. The second means we spew out warnings
(ew) and the compiler doesn't insert the `return` we omitted, and main just
falls of the end and does whatever undefined behavior (if you're luck, ud2
leading to non-zero return code).

Let's start my work with the basics. This patch changes all libc++ tests to
declare `main` as `int main(int, char**` so it mangles consistently (enabling us
to declare another `extern "C"` main for freestanding which calls the mangled
one), and adds `return 0;` to all places where it was missing. This touches 6124
files, and I apologize.

The former was done with The Magic Of Sed.

The later was done with a (not quite correct but decent) clang tool:

  https://gist.github.com/jfbastien/793819ff360baa845483dde81170feed

This works for most tests, though I did have to adjust a few places when e.g.
the test runs with `-x c`, macros are used for main (such as for the filesystem
tests), etc.

Once this is in we can create a freestanding bot which will prevent further
regressions. After that, we can start the real work of supporting C++
freestanding fairly well in libc++.

<rdar://problem/47754795>

Reviewers: ldionne, mclow.lists, EricWF

Subscribers: christof, jkorous, dexonsmith, arphaman, miyuki, libcxx-commits

Differential Revision: https://reviews.llvm.org/D57624

llvm-svn: 353086
2019-02-04 20:31:13 +00:00
Chandler Carruth 57b08b0944 Update more file headers across all of the LLVM projects in the monorepo
to reflect the new license. These used slightly different spellings that
defeated my regular expressions.

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: 351648
2019-01-19 10:56:40 +00:00
Eric Fiselier 84685fc831 Remove unused local var. Patch from STL@microsoft.com
llvm-svn: 272622
2016-06-14 02:55:21 +00:00
Eric Fiselier eb066bc29d Fix TEST_HAS_NO_EXCEPTIONS misspelling in the test suite.
llvm-svn: 271501
2016-06-02 08:19:02 +00:00
Eric Fiselier 4efa1ad561 Mark LWG issue 2250 as complete
llvm-svn: 271475
2016-06-02 04:03:31 +00:00
Eric Fiselier 92499e455e Remove test_atomic.h header
Because <atomic> can now be used in C++03 there is no need for the test_atomic.h header.
This commit removes the header and converts all usages to use <atomic> instead.

llvm-svn: 245468
2015-08-19 17:37:34 +00:00
Eric Fiselier 9c039962ca Use TestAtomic instead of std::atomic so the test can run in C++03
llvm-svn: 245415
2015-08-19 05:00:36 +00:00
Eric Fiselier 513ae1854d Fix race condition in thread test.
llvm-svn: 237745
2015-05-19 23:41:04 +00:00
Eric Fiselier 5a83710e37 Move test into test/std subdirectory.
llvm-svn: 224658
2014-12-20 01:40:03 +00:00