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
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
test/std/containers/sequences/vector.bool/copy.pass.cpp
test/std/containers/sequences/vector.bool/copy_alloc.pass.cpp
test/std/containers/sequences/vector/vector.cons/copy.pass.cpp
test/std/containers/sequences/vector/vector.cons/copy_alloc.pass.cpp
Change "unsigned s = x.size();" to "typename C::size_type s = x.size();"
because that's what it returns.
test/std/strings/basic.string/string.cons/pointer_alloc.pass.cpp
Include <cstddef>, then change "unsigned n = T::length(s);"
to "std::size_t n = T::length(s);" because that's what char_traits returns.
test/std/strings/basic.string/string.cons/substr.pass.cpp
Change unsigned to typename S::size_type because that's what str.size() returns.
test/std/utilities/template.bitset/bitset.cons/ull_ctor.pass.cpp
This was needlessly truncating std::size_t to unsigned.
It's being used to compare and initialize std::size_t.
llvm-svn: 288753
Various changes:
test/std/algorithms/alg.sorting/alg.merge/inplace_merge.pass.cpp
This is comparing value_type to unsigned. value_type is sometimes int and sometimes struct S (implicitly constructible from int).
static_cast<value_type>(unsigned) silences the warning and doesn't do anything bad (as the values in question are small).
test/std/algorithms/alg.sorting/alg.nth.element/nth_element_comp.pass.cpp
This is comparing an int remote-element to size_t. The values in question are small and non-negative,
so either type is fine. I think that converting int to size_t is marginally better here than the reverse.
test/std/containers/sequences/deque/deque.cons/size.pass.cpp
DefaultOnly::count is int (and non-negative). When comparing to unsigned, use static_cast<unsigned>.
test/std/strings/basic.string/string.access/index.pass.cpp
We're comparing char to '0' through '9', but formed with the type size_t. Add static_cast<char>.
test/std/utilities/template.bitset/bitset.cons/ull_ctor.pass.cpp
Include <cstddef> for pedantic correctness (this test was already mentioning std::size_t).
"v[i] == (i & 1)" was comparing bool to size_t. Saying "v[i] == ((i & 1) != 0)" smashes the RHS to bool.
llvm-svn: 288749
Fixes a small omission in libcxx that prevents libcxx being built when
-DLIBCXX_ENABLE_EXCEPTIONS=0 is specified.
This patch adds XFAILS to all those tests that are currently failing
on the new -fno-exceptions library variant. Follow-up patches will
update the tests (progressively) to cope with the new library variant.
Change-Id: I4b801bd8d8e4fe7193df9e55f39f1f393a8ba81a
llvm-svn: 252598
Eric Fiselier