note that FromStr does not work for borrowed types

[steveklabnik]

Fixes #47757

[rust-highfive]

r? @Mark-Simulacrum

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[rust-highfive]

The job x86_64-gnu-llvm-6.0 of your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

travis_fold:start:worker_info
Worker information
hostname: c2281654-c580-437f-b94d-53fd6b51bf71@1.production-1-worker-com-gce-dhzm
version: v6.2.0 https://github.com/travis-ci/worker/tree/5e5476e01646095f48eec13196fdb3faf8f5cbf7
startup: 6.537871547s
travis_fold:end:worker_info
travis_fold:start:system_info
Build system information
---
travis_time:end:08a5bddf:start=1547152926307852151,finish=1547152927417908077,duration=1110055926
$ git checkout -qf FETCH_HEAD
travis_fold:end:git.checkout

Encrypted environment variables have been removed for security reasons.
See https://docs.travis-ci.com/user/pull-requests/#pull-requests-and-security-restrictions
$ export SCCACHE_BUCKET=rust-lang-ci-sccache2
$ export SCCACHE_REGION=us-west-1
Setting environment variables from .travis.yml
$ export IMAGE=x86_64-gnu-llvm-6.0
---
[00:04:03] tidy error: /checkout/src/libcore/str/mod.rs:31: trailing whitespace
[00:04:05] some tidy checks failed
[00:04:05] 
[00:04:05] 
[00:04:05] command did not execute successfully: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-tools-bin/tidy" "/checkout/src" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0/bin/cargo" "--no-vendor" "--quiet"
[00:04:05] 
[00:04:05] 
[00:04:05] failed to run: /checkout/obj/build/bootstrap/debug/bootstrap test src/tools/tidy
[00:04:05] Build completed unsuccessfully in 0:00:48
[00:04:05] Build completed unsuccessfully in 0:00:48
[00:04:05] make: *** [tidy] Error 1
[00:04:05] Makefile:69: recipe for target 'tidy' failed
The command "stamp sh -x -c "$RUN_SCRIPT"" exited with 2.
travis_time:start:039f7000
$ date && (curl -fs --head https://google.com | grep ^Date: | sed 's/Date: //g' || true)
Thu Jan 10 20:46:25 UTC 2019
---
travis_time:end:0116c897:start=1547153186368427731,finish=1547153186373485481,duration=5057750
travis_fold:end:after_failure.3
travis_fold:start:after_failure.4
travis_time:start:0c384800
$ ln -s . checkout && for CORE in obj/cores/core.*; do EXE=$(echo $CORE | sed 's|obj/cores/core\.[0-9]*\.!checkout!\(.*\)|\1|;y|!|/|'); if [ -f "$EXE" ]; then printf travis_fold":start:crashlog\n\033[31;1m%s\033[0m\n" "$CORE"; gdb --batch -q -c "$CORE" "$EXE" -iex 'set auto-load off' -iex 'dir src/' -iex 'set sysroot .' -ex bt -ex q; echo travis_fold":"end:crashlog; fi; done || true
travis_fold:end:after_failure.4
travis_fold:start:after_failure.5
travis_time:start:05f1e94c
travis_time:start:05f1e94c
$ cat ./obj/build/x86_64-unknown-linux-gnu/native/asan/build/lib/asan/clang_rt.asan-dynamic-i386.vers || true
cat: ./obj/build/x86_64-unknown-linux-gnu/native/asan/build/lib/asan/clang_rt.asan-dynamic-i386.vers: No such file or directory
travis_fold:end:after_failure.5
travis_fold:start:after_failure.6
travis_time:start:2b96ed00
$ dmesg | grep -i kill

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN. (Feature Requests)

[Mark-Simulacrum]

r=me with tidy satisfied

[steveklabnik]

@bors: r=Mark-Simulacrum rollup

[bors]

📌 Commit beb6495 has been approved by Mark-Simulacrum