Since bedf657d0f4c54ffe9ef4303382657a74296b544 in llvm-project
(May 18th), a static libc++ built at the same time as a shared one
no longer contain dllexport directives, making that library actually
usable.
Since dfa88927ae1411ccc3b248b7e624f2acf623d947 (Jun 6th), the
libc++ headers no longer have dllimport attributes, making the headers
installed from a build containing a shared library usable both
for the shared and static library, without the user having to set
any specific defines.
These two changes allow removing the manual build workarounds of
building the libraries in separate CMake invocations in a specific
order.
Notable changes are:
- Fix stripping Rust executables with .rmeta sections
- Implemented support for SEH unwind info on the armv7 target
- Fix compiling files specified with an absolute \\?\C:\... style path
- Implemented support for the --disable-reloc-section option in lld
- Lots of improvements in LLDB on Windows (thanks to Alvin Wong!)
- Support for GNU debuglink
- Fix loading DLLs from a ramdisk
- Fix starting executables without including the '.exe' suffix
- Fixed crashes on getting nested exceptions
- Use the right C++ ABI for mingw environments
Other changes that simplify how to build the toolchain:
- Improvements to how libcxx/libcxxabi/libunwind are built for Windows
(and in particular mingw), allowing building both shared and static
libraries in the same cmake build
- Avoids needing to set an empty CROSS_TOOLCHAIN_FLAGS_NATIVE when
cross compiling LLVM
Notable changes are:
- Fix building for armv7 with SEH enabled
- Implement _set_com_error_handler and _com_raise_error in comdef.h
- Add import libraries for older msvcrXX.dll versions
- Redirect access() to __mingw_access() on UCRT
- Assorted updates to Windows APIs
Zstd is available and gets autodetected, but it's only available in
native form, not in arm64 form.
Also, for the existing workaround, instead of entirely disabling lldb,
one could pass -DLLDB_ENABLE_PYTHON=OFF instead.
Test building the toolchain on all supported platforms for building
it (linux, macOS, msys2). Produce cross-built standalone toolchains
that run on Windows for all 4 supported architectures.
Run scheduled builds (daily), built with the latest git versions of
most components. For scheduled builds, the linux toolchain is built
with assertions enabled, as latest git version of llvm occasionally
can have regressions, and many such are caught by having assertions
enabled and building enough code that exercise many code generation
cases.
A regular GCC install doesn't provide tools like <triple>-{cc,c99,c11},
so there's probably not much need to include them.
Some distributions of tools may provide tools with the names "cc",
"c99" and "c11" though, as custom frontends or symlinks to the
regular compiler. Therefore, keep the unprefixed tools with these
names.
Check for the prescence of the llvm-tblgen binary in addition to just
checking whether the llvm/build or llvm/build-asserts directories
exist.
In cases where having multiple build directories around, where some
are older than others, it's now possible to clarify which one to use
for tools by just removing the llvm-tblgen binary from the other ones.
Also check for the prescenece of each individual tool before setting
it; this fixes builds where the native build might not have all
components enable as as enabled in the cross build.
The install(1) tool on macOS doesn't support the -D option for
creating directories at the same time while installing files.
Therefore, run a separate step for creating directories. Doing that
with "mkdir -p", even if install(1) also could do that with the -d
option (likewise with a separate command).
Also stop specifying the destination file name, when it's equal to
the source files, now that we know that the destination directory
already exists.
Install copyright notices into the final package. This makes LLVM MinGW
comply with many of the licenses (which require attribution), and also
makes it easier for users of LLVM MinGW to audit licenses of software
they use.
Compared with RC2, the only notable change for mingw targets is
that sections named .debug_* are sorted to the very end of the
image, after any other discardable sections, avoiding leaving gaps
if stripping such executables. (This can affect rust binaries with
a .rmeta section.)
This fixes the v*scanf functions when using msvcrt.dll, if using more
than 30 format conversions, fixes error handling in the btowc
function in libmingwex, and adds a missing (void) in a function
prototype in winpthreads, adds the fwpuclnt import library for aarch64,
plus other assorted header/interface updates.
This installs a bunch of new tools in the bin dir, namely the following:
clang-apply-replacements
clang-change-namespace
clang-doc
clang-include-fixer
clang-move
clang-query
clang-reorder-fields
clang-tidy
clangd
find-all-symbols
modularize
pp-trace
run-clang-tidy
These are stripped out by strip-llvm, but clangd and clang-tidy
are kept.
While lldb can be used as a cross debugger, it's probably mostly
used when run on the same target as the code is executed on.
Since it's a mostly optional component in the toolchain, allow
passing --disable-lldb to build-llvm.sh to skip it.
Allow setting up the projects with symlinks by passing --symlink-projects
to the build script.
The setup with symlinks is mostly useful in development setups, where
one wants to share ccache across multiple checkouts.
If the SYNC variable is set when running build-all.sh, all the
individual scripts will try to check out the intended version
before building. All scripts that build projects from llvm-project
(build-libcxx.sh, build-compiler-rt.sh, build-openmp.sh) call
build-llvm.sh with CHECKOUT_ONLY=1 to make sure the right version
is checked out (as one can call the scripts individually too).
If the llvm-project directory was a full (non-shallow) checkout,
the repeated fetch was quick as git knew that it had the fetched
reference already. But in a shallow clone, a new shallow fetch
would refetch the whole object tree for the targeted reference.
Using "git cat-file -e" we can check whether a specific object
exists in the local checkout, avoiding needlessly refetching
everything.
However, when fetching a tag using shallow fetch (git fetch
--depth 1 origin "$LLVM_VERSION"), it would only fetch the
commit object for that tag, not the tag itself. By specifying
'tag "$LLVM_VERSION"' in this case, we get the tag object itself,
so that we later can check whether "$LLVM_VERSION" exists in the
local checkout. But this requires guessing whether a specific
"$LLVM_VERSION" is a tag or a commit.
This reverts commit bd9e16f732.
It turns out this actually isn't needed; since switching to
building via the llvm-project/runtimes directory (in
7b1d05f545), the cmake build
pulls in HandleLLVMOptions.cmake, which checks for and adds
-ffunction-sections and -fdata-sections if supported. Therefore,
we don't need to specify it manually at all.
Notable changes include:
- Default to DWARF 4 instead of 5 for the mingw target
- Fix the section name encoding in llvm-objcopy/llvm-strip, if the output
binary has more than 10^6 bytes of string table
Clang's general default dwarf version was raised from 4 to 5 in
d3b26dea16108c427b19b5480c9edc76edf8f5b4 in llvm-project (Jan 23
2022) before the 14.0.0 branch, but dwarf 5 on Windows seems to not
work with either LLDB or GDB.
Thus force the default back to 4 here as a temporary workaround, and try
to set the default back to 4 for mingw targets in Clang for later
releases (https://reviews.llvm.org/D119326).
This includes building universal binaries (for arm64 and x86_64)
and targeting an older minimum deployment target.
(Before 1919720fdd348ca568b235bf3f1357c198eccd15 in llvm-project,
Jan 2022, building lldb's debugserver failed, if building for macOS
for multiple architectures, or for an architecture other than the
current host.)
This makes warnings for other unused arguments visible to the user.
This requires a version of llvm-project past
50ec1306d060e46e0d53c9f5d8a052e1b0d10d3b (Jan 2022) which added these
new options.
This reverts parts of commit e35ef3b7d7.
This is now handled better upstream, since
7af584ed87cc6eddb6adbc451c90fb8867469e06 in llvm-project
(November 5th 2021).
When --unwindlib=libunwind is implicit, we need to build libunwind
to have a complete working C compiler too. Currently this is worked
around by initially creating a dummy, empty libunwind.a, but with
the current version of libcxx/libunwind, we can get rid of that
workaround if we build it as soon as possible.
Since df0ba47c36f6bd0865e3286853b76d37e037c2d7 in llvm-project
(November 5th 2021), clang built with mingw defaults to producing
paths with forward slashes - thus, this hack no longer is needed.
Since a8d15a926689c126c4d316788786e0160cfc1d5d in llvm-project
(October 5th), libcxx stopped autodetecting pthreads on mingw,
making pthreads opt-in instead of opt-out.
Martin Storsjö