rust-cross build failure due to missing llvm symbols using cxx11 references

[codyps]

Doesn't happen on all systems. I've observed this on arch linux, but not on gentoo. Might depend on whether the system gcc has the new cxx11 abi enabled.

Probably due to uninative.bbclass from selectively disabling gcc's new cxx11 abi & cross.bbclass having a different *_CXXFLAGS compared to native.bbclass

# https://wiki.debian.org/GCC5
# We may see binaries built with gcc5 run or linked into gcc4 environment
# so use the older libstdc++ standard for now until we don't support gcc4
# on the host system.
BUILD_CXXFLAGS_append = " -D_GLIBCXX_USE_CXX11_ABI=0"

Full error output

| error: linking with `gcc` failed: exit code: 1
| note: "gcc" "-Wl,--enable-new-dtags" "-Wl,--as-needed" "-m64" "-L" "x86_64-linux/stage0/lib/rustlib/x86_64-linux/lib" "x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/bin/rustc.0.o" "-o" "x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/bin/rustc" "-Wl,--gc-sections" "-Wl,-O1" "-nodefaultlibs" "-L" "x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-L" "/home/cody/obj/y/tmp/sysroots/x86_64-linux/usr/lib" "-L" "x86_64-linux/stage0/lib/rustlib/x86_64-linux/lib" "-Wl,-Bstatic" "-Wl,-Bdynamic" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "rustc_driver-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "rustc_passes-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "rustc_borrowck-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "rustc_privacy-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "rustc_typeck-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "rustc_lint-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "rustc_resolve-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "syntax_ext-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "rustc_plugin-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "rustc_metadata-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "rustc_trans-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "rustc_platform_intrinsics-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "rustc_mir-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "rustc-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "rustc_data_structures-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "rustc_back-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "flate-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "getopts-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "arena-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "fmt_macros-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "graphviz-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "rustc_front-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "syntax-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "term-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "rustc_llvm-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "rbml-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "serialize-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "log-ca1c970e" "-L" "/home/cody/obj/y/tmp/work/x86_64-linux/rust-cross-arm/1.7.0-r0/build/x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib" "-l" "std-ca1c970e" "-l" "pthread" "-l" "edit" "-l" "dl" "-l" "m" "-l" "stdc++" "-l" "dl" "-l" "pthread" "-l" "gcc_s" "-l" "c" "-l" "m" "-l" "rt" "-Wl,-rpath,$ORIGIN/../lib" "-Wl,-rpath,/usr/local/lib/rustlib/x86_64-linux/lib" "-l" "compiler-rt" "-L/home/cody/obj/y/tmp/sysroots/x86_64-linux/usr/lib" "-L/home/cody/obj/y/tmp/sysroots/x86_64-linux/lib" "-Wl,-rpath-link,/home/cody/obj/y/tmp/sysroots/x86_64-linux/usr/lib" "-Wl,-rpath-link,/home/cody/obj/y/tmp/sysroots/x86_64-linux/lib" "-Wl,-rpath,/home/cody/obj/y/tmp/sysroots/x86_64-linux/usr/lib" "-Wl,-rpath,/home/cody/obj/y/tmp/sysroots/x86_64-linux/lib" "-Wl,-O1" "-Wl,-rpath=../../lib"
| note: x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib/librustc_llvm-ca1c970e.so: undefined reference to `llvm::TargetRegistry::lookupTarget(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&)'
| x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib/librustc_llvm-ca1c970e.so: undefined reference to `llvm::RTDyldMemoryManager::getSymbolAddressInProcess(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)'
| x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib/librustc_llvm-ca1c970e.so: undefined reference to `llvm::sys::DynamicLibrary::getPermanentLibrary(char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >*)'
| x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib/librustc_llvm-ca1c970e.so: undefined reference to `llvm::createPrintModulePass(llvm::raw_ostream&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, bool)'
| x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib/librustc_llvm-ca1c970e.so: undefined reference to `llvm::report_fatal_error(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, bool)'
| x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib/librustc_llvm-ca1c970e.so: undefined reference to `llvm::SectionMemoryManager::finalizeMemory(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >*)'
| x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib/librustc_llvm-ca1c970e.so: undefined reference to `llvm::Triple::normalize[abi:cxx11](llvm::StringRef)'
| x86_64-linux/stage0/lib/arm-poky-linux-gnueabi/rustlib/x86_64-linux/lib/librustc_llvm-ca1c970e.so: undefined reference to `llvm::RTDyldMemoryManager::getPointerToNamedFunction(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, bool)'

[hmvp]

I am seeing this on Ubuntu 16.04 x86_64 with up to date krogoth build for beaglebone

[cardoe]

You probably didn't see this on Gentoo because you weren't using gcc-5 there at the time. It's starting to crop up. https://bugs.gentoo.org/show_bug.cgi?id=571600

[hmvp]

diff --git a/src/librustc_back/target/linux_base.rs b/src/librustc_back/target/linux_base.rs
index d1ab71e..13071b6 100644
--- a/src/librustc_back/target/linux_base.rs
+++ b/src/librustc_back/target/linux_base.rs
@@ -29,6 +29,9 @@ pub fn opts() -> TargetOptions {

             // Always enable NX protection when it is available
             "-Wl,-z,noexecstack".to_string(),
+
+            //Don't use new C++ ABI just like Yocto does
+            "-D_GLIBCXX_USE_CXX11_ABI=0".to_string()
         ],
         position_independent_executables: true,
         exe_allocation_crate: super::maybe_jemalloc(),

as patch seems to help
This could probably be done nicer

[codyps]

I've done this in my yocto config to avoid failures here. This disables all use of the CXX11 ABI. Probably not necessary to be this heavy handed.

BUILD_CXXFLAGS_append = " -D_GLIBCXX_USE_CXX11_ABI=0"
TARGET_CXXFLAGS_append = " -D_GLIBCXX_USE_CXX11_ABI=0"
CXXFLAGS_append = " -D_GLIBCXX_USE_CXX11_ABI=0"

BUILD_CXXFLAGS_remove_pn-gcc-runtime = "-D_GLIBCXX_USE_CXX11_ABI=0"
TARGET_CXXFLAGS_remove_pn-gcc-runtime = "-D_GLIBCXX_USE_CXX11_ABI=0"
CXXFLAGS_remove_pn-gcc-runtime = "-D_GLIBCXX_USE_CXX11_ABI=0"

Note that without the _remove bits gcc-runtime tries to build 2 non-cxx11-abi variants instead of one with cxx11-abi and one without. This duplication shows up as a link failure due to duplicate symbols.