compiler_builtins 0.1.20 (likely) broke xargo compilation

[RalfJung]

Since compiler_builtins 0.1.20 was released, Miri is broken on macOS and Windows as xargo fails to build libstd. (Currently latest xargo ignores the lockfile, so it will always build libstd with the latest version of all involved crates. A fix for that is hopefully going to be released soon, but that seems orthogonal.)

On Windows, the error is

error: linking with `link.exe` failed: exit code: 1120
  |
  = note: "C:\\Program Files (x86)\\Microsoft Visual Studio 14.0\\VC\\bin\\amd64\\link.exe" "/NOLOGO" "/NXCOMPAT" "/LIBPATH:C:\\Users\\appveyor\\AppData\\Local\\rust-lang\\miri\\cache\\HOST\\lib\\rustlib\\x86_64-pc-windows-msvc\\lib" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.std.9frsuiy7-cgu.0.rcgu.o" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.std.9frsuiy7-cgu.1.rcgu.o" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.std.9frsuiy7-cgu.10.rcgu.o" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.std.9frsuiy7-cgu.11.rcgu.o" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.std.9frsuiy7-cgu.12.rcgu.o" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.std.9frsuiy7-cgu.13.rcgu.o" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.std.9frsuiy7-cgu.14.rcgu.o" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.std.9frsuiy7-cgu.15.rcgu.o" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.std.9frsuiy7-cgu.2.rcgu.o" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.std.9frsuiy7-cgu.3.rcgu.o" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.std.9frsuiy7-cgu.4.rcgu.o" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.std.9frsuiy7-cgu.5.rcgu.o" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.std.9frsuiy7-cgu.6.rcgu.o" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.std.9frsuiy7-cgu.7.rcgu.o" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.std.9frsuiy7-cgu.8.rcgu.o" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.std.9frsuiy7-cgu.9.rcgu.o" "/OUT:C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.dll" "/DEF:C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\rustcuPQ9c1\\lib.def" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.2qzihvbkmjhq7pfa.rcgu.o" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.4f5mgpkh8dli7sc3.rcgu.o" "/OPT:REF,ICF" "/DEBUG" "/LIBPATH:C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps" "/LIBPATH:C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\release\\deps" "/LIBPATH:C:\\Users\\appveyor\\AppData\\Local\\rust-lang\\miri\\cache\\HOST\\lib\\rustlib\\x86_64-pc-windows-msvc\\lib" "advapi32.lib" "ws2_32.lib" "userenv.lib" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\rustcuPQ9c1\\libpanic_unwind-275f615d9b39f3f1.rlib" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\rustcuPQ9c1\\libhashbrown-590ae4c0395f691e.rlib" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\rustcuPQ9c1\\librustc_std_workspace_alloc-3d6a7ba205ab520a.rlib" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\rustcuPQ9c1\\libbacktrace-00e9a9ccf2272490.rlib" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\rustcuPQ9c1\\librustc_demangle-baf1d7d5cac013c3.rlib" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\rustcuPQ9c1\\libunwind-bf411db0c0e3a904.rlib" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\rustcuPQ9c1\\libcfg_if-dbb439db3e845984.rlib" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\rustcuPQ9c1\\liblibc-40cce4e31e001aba.rlib" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\rustcuPQ9c1\\liballoc-d04d3bd41898dd94.rlib" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\rustcuPQ9c1\\librustc_std_workspace_core-dea927fe85ff3b02.rlib" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\rustcuPQ9c1\\libcore-ea34e7f78ace01ca.rlib" "C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\rustcuPQ9c1\\libcompiler_builtins-37c094553672d784.rlib" "msvcrt.lib" "/DLL" "/IMPLIB:C:\\Users\\appveyor\\AppData\\Local\\Temp\\1\\xargo.4aGLo778seq6\\target\\x86_64-pc-windows-msvc\\release\\deps\\std.dll.lib"
  = note:    Creating library C:\Users\appveyor\AppData\Local\Temp\1\xargo.4aGLo778seq6\target\x86_64-pc-windows-msvc\release\deps\std.dll.lib and object C:\Users\appveyor\AppData\Local\Temp\1\xargo.4aGLo778seq6\target\x86_64-pc-windows-msvc\release\deps\std.dll.exp
          libcompiler_builtins-37c094553672d784.rlib(compiler_builtins-37c094553672d784.compiler_builtins.1coylv34-cgu.5.rcgu.o) : error LNK2019: unresolved external symbol __sync_val_compare_and_swap_16 referenced in function __llvm_memcpy_element_unordered_atomic_16
          libcompiler_builtins-37c094553672d784.rlib(compiler_builtins-37c094553672d784.compiler_builtins.1coylv34-cgu.5.rcgu.o) : error LNK2019: unresolved external symbol __sync_lock_test_and_set_16 referenced in function __llvm_memcpy_element_unordered_atomic_16
          C:\Users\appveyor\AppData\Local\Temp\1\xargo.4aGLo778seq6\target\x86_64-pc-windows-msvc\release\deps\std.dll : fatal error LNK1120: 2 unresolved externals
          
error: aborting due to previous error
error: could not compile `std`.

and on macOS, it starts with

error: linking with `cc` failed: exit code: 1

  |

  = note: "cc" "-m32" "-L" "/Users/travis/Library/Caches/org.rust-lang.miri/lib/rustlib/i686-apple-darwin/lib" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps/std.std.8sfdv10m-cgu.0.rcgu.o" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps/std.std.8sfdv10m-cgu.1.rcgu.o" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps/std.std.8sfdv10m-cgu.10.rcgu.o" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps/std.std.8sfdv10m-cgu.11.rcgu.o" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps/std.std.8sfdv10m-cgu.12.rcgu.o" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps/std.std.8sfdv10m-cgu.13.rcgu.o" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps/std.std.8sfdv10m-cgu.14.rcgu.o" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps/std.std.8sfdv10m-cgu.15.rcgu.o" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps/std.std.8sfdv10m-cgu.2.rcgu.o" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps/std.std.8sfdv10m-cgu.3.rcgu.o" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps/std.std.8sfdv10m-cgu.4.rcgu.o" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps/std.std.8sfdv10m-cgu.5.rcgu.o" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps/std.std.8sfdv10m-cgu.6.rcgu.o" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps/std.std.8sfdv10m-cgu.7.rcgu.o" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps/std.std.8sfdv10m-cgu.8.rcgu.o" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps/std.std.8sfdv10m-cgu.9.rcgu.o" "-o" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps/libstd.dylib" "-Wl,-exported_symbols_list,/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/rustcucaNs8/list" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps/std.2lg0awms1xbqknxx.rcgu.o" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps/std.4i86n2lmpfdbpci3.rcgu.o" "-Wl,-dead_strip" "-nodefaultlibs" "-L" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/deps" "-L" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/release/deps" "-L" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/xargo.hwyVdmi27hf6/target/i686-apple-darwin/release/build/backtrace-sys-e15093736628d2c1/out" "-L" "/Users/travis/Library/Caches/org.rust-lang.miri/lib/rustlib/i686-apple-darwin/lib" "-lSystem" "-lresolv" "-Wl,-force_load" "-Wl,/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/rustcucaNs8/libpanic_unwind-574d9f2b20722c6c.rlib" "-Wl,-force_load" "-Wl,/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/rustcucaNs8/libhashbrown-8c9410f43c34c375.rlib" "-Wl,-force_load" "-Wl,/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/rustcucaNs8/librustc_std_workspace_alloc-0a921424f3e15b5f.rlib" "-Wl,-force_load" "-Wl,/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/rustcucaNs8/libbacktrace-8630f1fe1b083f0a.rlib" "-Wl,-force_load" "-Wl,/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/rustcucaNs8/librustc_demangle-844493b74214a800.rlib" "-Wl,-force_load" "-Wl,/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/rustcucaNs8/libunwind-0bbc6edf26ee0820.rlib" "-Wl,-force_load" "-Wl,/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/rustcucaNs8/libcfg_if-f2ef1f45d53b2bd2.rlib" "-Wl,-force_load" "-Wl,/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/rustcucaNs8/liblibc-16470196836e92e2.rlib" "-Wl,-force_load" "-Wl,/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/rustcucaNs8/liballoc-cdac88354d321e5c.rlib" "-Wl,-force_load" "-Wl,/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/rustcucaNs8/librustc_std_workspace_core-d76be33b42b0f265.rlib" "-Wl,-force_load" "-Wl,/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/rustcucaNs8/libcore-f92fb94d33fd15c9.rlib" "/var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/rustcucaNs8/libcompiler_builtins-cb06eb4f5cb108d6.rlib" "-lc" "-lm" "-dynamiclib" "-Wl,-dylib"

  = note: ld: warning: cannot export hidden symbol compiler_builtins::mem::memcpy::h1f97dfde851c02dc from /var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/rustcucaNs8/libcompiler_builtins-cb06eb4f5cb108d6.rlib(compiler_builtins-cb06eb4f5cb108d6.compiler_builtins.crtnmu5o-cgu.5.rcgu.o)

          ld: warning: cannot export hidden symbol compiler_builtins::mem::memmove::h870d040713cf2ddf from /var/folders/nz/vv4_9tw56nv9k3tkvyszvwg80000gn/T/rustcucaNs8/libcompiler_builtins-cb06eb4f5cb108d6.rlib(compiler_builtins-cb06eb4f5cb108d6.compiler_builtins.crtnmu5o-cgu.5.rcgu.o)
[...]

[RalfJung]

Or maybe that breakage is expected? Are compiler_builtins updates semver-compatible in the sense that old compilers can still work when using newer compiler_builtins?

[mati865]

Most likely cause: #311

[alexcrichton]

I think this should be fixed with #324, and when merged I'll make a new release. Thanks for the report!