[fuzzer][test] Disable noasan-strncmp test for AArch64

[antmo]

Summary

This test fails on several aarch64 bots

clang-aarch64-lld-2stage ( https://lab.llvm.org/buildbot/#/builders/185/builds/3525 )
clang-aarch64-full-2stage ( https://lab.llvm.org/buildbot/#/builders/179/builds/5904 )
clang-aarch64-sve-vla ( https://lab.llvm.org/buildbot/#/builders/197/builds/4519 )

Disable it while this is analyzed.

[antmo]

I dont get it for now. There is only one patch between the last success ( https://lab.llvm.org/buildbot/#/builders/197/builds/4518 ) and the first failure ( https://lab.llvm.org/buildbot/#/builders/179/builds/5904 ) : https://reviews.llvm.org/D147121 ( b356cd70a27d )
But this is very unlikely due to this patch, as it should have no effect on linux (and -pie is enabled when I reproduce the failure)

[DavidSpickett]

I suspect this test is sensitive to fluctuations in resources. With us running large shared machines that can happen a lot, despite fixing parts of it, like core count, for some containers. Potentially we could reproduce by running stress inside a container while running this test on its own.

compiler-rt/test/fuzzer/noasan-strncmp.test

1

You should use the newer syntax: https://github.com/llvm/llvm-project/commit/8a86860207f0d5c794a2b8c0b384001710e5d036

For example another test that excludes windows and aarch64:

UNSUPPORTED: darwin, target={{.*windows.*}}, target=aarch64{{.*}}

(I think darwin doesn't use it because the word darwin doesn't appear in the target triple)

[DavidSpickett]

Also you are right to use UNSUPPORTED not XFAIL, because when an XFAIL passes it becomes an XPASS, which is, itself, a failure.

If that makes any sense at all :)

[antmo]

update

[DavidSpickett]

LGTM, do you have commit access yet?

[antmo]

In D148332#4268532, @DavidSpickett wrote:

LGTM, do you have commit access yet?

not yet ;)

compiler-rt/test/fuzzer/noasan-strncmp.test

-UNSUPPORTED: darwin, target={{.*(freebsd|windows).*}}
+UNSUPPORTED: darwin, target={{.*(freebsd|windows).*}}, target=aarch64{{.*}}
 
 RUN: %cpp_compiler -fno-sanitize=address %S/StrncmpTest.cpp -o %t-NoAsanStrncmpTest
 RUN: not %run %t-NoAsanStrncmpTest -seed=2 -runs=10000000   2>&1 | FileCheck %s
 
 RUN: %cpp_compiler -fno-sanitize=address -fno-builtin-calloc %S/CustomAllocator.cpp %S/StrncmpTest.cpp -o %t-NoAsanCustomAllocatorStrncmpTest
 RUN: not %run %t-NoAsanCustomAllocatorStrncmpTest -seed=2 -runs=10000000   2>&1 | FileCheck %s
 
 CHECK: BINGO