$ cargo new --bin a
     Created binary (application) `a` package
$ cd a/
$ echo -e '[profile.dev]\nlto="fat"' >> Cargo.toml 
$ cargo run -Zbuild-std --target x86_64-unknown-linux-gnu
...
error: linking with `cc` failed: exit code: 1
  |
  = note: "cc" "-Wl,--as-needed" "-Wl,-z,noexecstack" "-m64" "-L" "/../.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib" "/tmp/a/target/x86_64-unknown-linux-gnu/debug/deps/a-f6afee8bd619dd6c.10btgdcccpdgwv38.rcgu.o" "-o" "/tmp/a/target/x86_64-unknown-linux-gnu/debug/deps/a-f6afee8bd619dd6c" "-Wl,--gc-sections" "-pie" "-Wl,-zrelro" "-Wl,-znow" "-nodefaultlibs" "-L" "/tmp/a/target/x86_64-unknown-linux-gnu/debug/deps" "-L" "/tmp/a/target/debug/deps" "-L" "/tmp/a/target/x86_64-unknown-linux-gnu/debug/build/backtrace-sys-23683e5572d20c8c/out" "-L" "/../.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib" "-Wl,--start-group" "-Wl,-Bstatic" "/tmp/rustcgyDZiW/libbacktrace_sys-ba159dd14189807b.rlib" "-Wl,--end-group" "/tmp/a/target/x86_64-unknown-linux-gnu/debug/deps/libcompiler_builtins-495badfa0e51e0a1.rlib" "-Wl,-Bdynamic" "-ldl" "-lrt" "-lpthread" "-lgcc_s" "-lc" "-lm" "-lrt" "-lpthread" "-lutil" "-lutil"
  = note: /usr/bin/ld: /tmp/a/target/x86_64-unknown-linux-gnu/debug/deps/libcompiler_builtins-495badfa0e51e0a1.rlib(compiler_builtins-495badfa0e51e0a1.compiler_builtins.ecun6ipv-cgu.15.rcgu.o): in function `<i128 as core::ops::arith::Sub>::sub':
          /../.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/src/libcore/ops/arith.rs:194: undefined reference to `core::panicking::panic'
          /usr/bin/ld: /tmp/a/target/x86_64-unknown-linux-gnu/debug/deps/libcompiler_builtins-495badfa0e51e0a1.rlib(compiler_builtins-495badfa0e51e0a1.compiler_builtins.ecun6ipv-cgu.11.rcgu.o): in function `compiler_builtins::int::sdiv::Div::div':
          /../.cargo/registry/src/github.com-1ecc6299db9ec823/compiler_builtins-0.1.25/src/int/sdiv.rs:6: undefined reference to `core::panicking::panic'
          /usr/bin/ld: /../.cargo/registry/src/github.com-1ecc6299db9ec823/compiler_builtins-0.1.25/src/int/sdiv.rs:7: undefined reference to `core::panicking::panic'
          /usr/bin/ld: /tmp/a/target/x86_64-unknown-linux-gnu/debug/deps/libcompiler_builtins-495badfa0e51e0a1.rlib(compiler_builtins-495badfa0e51e0a1.compiler_builtins.ecun6ipv-cgu.11.rcgu.o): in function `compiler_builtins::int::sdiv::Mod::mod_':
          /../.cargo/registry/src/github.com-1ecc6299db9ec823/compiler_builtins-0.1.25/src/int/sdiv.rs:28: undefined reference to `core::panicking::panic'
          /usr/bin/ld: /../.cargo/registry/src/github.com-1ecc6299db9ec823/compiler_builtins-0.1.25/src/int/sdiv.rs:31: undefined reference to `core::panicking::panic'
          /usr/bin/ld: /tmp/a/target/x86_64-unknown-linux-gnu/debug/deps/libcompiler_builtins-495badfa0e51e0a1.rlib(compiler_builtins-495badfa0e51e0a1.compiler_builtins.ecun6ipv-cgu.13.rcgu.o):/../.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/src/libcore/ops/bit.rs:515: more undefined references to `core::panicking::panic' follow
          collect2: error: ld returned 1 exit status
          

error: aborting due to previous error