Without the change build on mips64-unknown-linux-gnu fails as:
$ nix-build -A buildPackages.gcc12 --argstr crossSystem mips64-linux
In file included from ...-glibc-mips64-unknown-linux-gnu-2.37-8-dev/include/bits/stat.h:25,
from ...-glibc-mips64-unknown-linux-gnu-2.37-8-dev/include/fcntl.h:78,
from ../../../../gcc-12.3.0/libsanitizer/sanitizer_common/sanitizer_linux.cpp:55:
...-glibc-mips64-unknown-linux-gnu-2.37-8-dev/include/bits/struct_stat.h:190:8: error: redefinition of 'struct stat64'
190 | struct stat64
| ^~~~~~
What changed:
* Fixed crtbeginS.o and crtendS.o missing
(they may or may not be called crt{begin_end},{,_shared}.
* Fixed implicit function declaration causing build errors for various
builds by supplying -Wno-implicit-function-declaration.
* Fixed __cxxabi_config.h missing, by adding -I${cxxabi}/include/c++/v1
in the wrapper.
* Fixed libcxx failing to build due to missing libunwind symbols by
including libunwind as a buildInput, and setting
-DLIBCXX_ADDITIONAL_LIBRARIES=unwind for stdenv.hostPlatform.useLLVM == true.
* libcxxabi wants to find libunwind at libunwind_shared.so, so symlink
it there in libunwind.
* llvmPackages_16.libcxxabi: Pass -nostdlib via CMAKE_*_LINKER_FLAGS
Without this flag, the link of libcxxabi.so tries to pull in libgcc and
friends, from the clang compiler driver.
* Drop unneeded musl hack patch from libcxx.
* Pass -Wno-error=implicit-function-declaration only to compiler-rt
See LLVM forum discussion:
https://discourse.llvm.org/t/configure-script-breakage-with-the-new-werror-implicit-function-declaration/65213
In summary, LLVM 16 made implicit function declaration an error. This
happens a lot in configure scripts which can break things.
* llvmPackages_16: !isDarwin: Supply -DLIBCXX_ABI_USE_LLVM_UNWINDER=On
Otherwise it fails with various undefined references to _Unwind_*
functions: (full list: _Unwind_DeleteException _Unwind_GetIP
_Unwind_GetLanguageSpecificData _Unwind_GetRegionStart
_Unwind_RaiseException _Unwind_Resume _Unwind_SetGR _Unwind_SetIP).
* 16.libcxxabi: Only pass -nostdlib for useLLVM and Darwin builds
What was tested:
* x86_64-linux, aarch64-linux, the stdenv builds.
* Additionally I was able to get nix to build, with an overlay to fix
a couple of minor issues in downstream packages (overlay supplied in
PR #246577.
* aarch64-darwin fails spuriously in a single LLVM test
strip-preserve-atime.test checking atime timestamps.
* The same for pkgsLLVM with llvmPackages = llvmPackages_15.
Signed-off-by: Peter Waller <p@pwaller.net>
