[fuzzer][test] Avoid big-file-copy.test on memory constrained devices

[rsundahl]

Summary

The test "big-file-copy.test" introduced in D146189 and constrained to darwin by
D147094, is by this differential further constrained to only those devices with
sufficient resources. Also correct the test to read the environment variable
"result" from the same shell in which it was stored (which may differ on devices).

[rsundahl]

Update title and add Radar reference.

[rsundahl]

Change to improve title and summary.

[thetruestblue]

compiler-rt/test/fuzzer/big-file-copy.test

2

This is redundant. ios lit feature includes all ios derivatives:

# =========================================================================
# Target             | Feature set
# =========================================================================
# macOS              | darwin
# iOS device         | darwin, ios
# iOS simulator      | darwin, ios, iossim
# tvOS device        | darwin, ios, tvos
# tvOS simulator     | darwin, ios, iossim, tvos, tvossim
# watchOS device     | darwin, ios, watchos
# watchOS simulator  | darwin, ios, iossim, watchos, watchossim
# =========================================================================

[rsundahl]

compiler-rt/test/fuzzer/big-file-copy.test

2

Thank you! I meant to restrict tvOS and watchOS, not all iOS. I'll retest with the change and update.

[rsundahl]

ios->tvos

[rsundahl]

compiler-rt/test/fuzzer/big-file-copy.test

2

Updated to reflect that test should be active on iOS and derivatives other than tvOS and watchOS.

compiler-rt/test/fuzzer/big-file-copy.test

 REQUIRES: darwin
+UNSUPPORTED: tvos || watchos
 RUN: %cpp_compiler %S/BigFileCopy.cpp -o %t
 RUN: %run %t -runs=1 -rss_limit_mb=4096 2>big-file-out.txt; result=$?
 RUN: %run rm -f big-file.txt big-file-out.txt
-RUN: %run (exit $result)
+RUN: (exit $result)