add regression test for #48835

[euclio]

Fixes #48835.

The underlying issue was fixed in #51978.

[rust-highfive]

r? @aturon

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[rust-highfive]

The job x86_64-gnu-llvm-3.9 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.

[00:03:42] travis_fold:start:tidy
travis_time:start:tidy
tidy check
[00:03:42] tidy error: /checkout/src/test/ui/include-macros/mismatched-types.rs: incorrect license
[00:03:44] some tidy checks failed
[00:03:44] 
[00:03:44] 
[00:03:44] 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"
[00:03:44] 
[00:03:44] 
[00:03:44] failed to run: /checkout/obj/build/bootstrap/debug/bootstrap test src/tools/tidy
[00:03:44] Build completed unsuccessfully in 0:00:49
[00:03:44] Build completed unsuccessfully in 0:00:49
[00:03:44] Makefile:79: recipe for target 'tidy' failed
[00:03:44] make: *** [tidy] Error 1

The command "stamp sh -x -c "$RUN_SCRIPT"" exited with 2.
travis_time:start:0405c8a0
$ date && (curl -fs --head https://google.com | grep ^Date: | sed 's/Date: //g' || true)
---
travis_time:end:07984ae2:start=1531077898236735512,finish=1531077898242914382,duration=6178870
travis_fold:end:after_failure.3
travis_fold:start:after_failure.4
travis_time:start:196db2be
$ head -30 ./obj/build/x86_64-unknown-linux-gnu/native/asan/build/lib/asan/clang_rt.asan-dynamic-i386.vers || true
head: cannot open ‘./obj/build/x86_64-unknown-linux-gnu/native/asan/build/lib/asan/clang_rt.asan-dynamic-i386.vers’ for reading: No such file or directory
travis_fold:end:after_failure.4
travis_fold:start:after_failure.5
travis_time:start:398f19d2
$ dmesg | grep -i kill

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[oli-obk]

@bors r+ rollup

[bors]

📌 Commit 1be1d90 has been approved by oli-obk

[bors]

⌛ Testing commit 1be1d90 with merge c30acc7...

[bors]

☀️ Test successful - status-appveyor, status-travis
Approved by: oli-obk
Pushing c30acc7 to master...