[compiler-rt] Fix GetRandom in sanitizer_fuchsia.cpp (PR #110155)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `sanitizer-x86_64-linux-fast` running on `sanitizer-buildbot4` while building `compiler-rt` at step 2 "annotate".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/169/builds/4561

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 2 (annotate) failure: 'python ../sanitizer_buildbot/sanitizers/zorg/buildbot/builders/sanitizers/buildbot_selector.py' (failure)
...
llvm-lit: /home/b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:506: note: using ld64.lld: /home/b/sanitizer-x86_64-linux-fast/build/llvm_build_asan_ubsan/bin/ld64.lld
llvm-lit: /home/b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:506: note: using wasm-ld: /home/b/sanitizer-x86_64-linux-fast/build/llvm_build_asan_ubsan/bin/wasm-ld
llvm-lit: /home/b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:506: note: using ld.lld: /home/b/sanitizer-x86_64-linux-fast/build/llvm_build_asan_ubsan/bin/ld.lld
llvm-lit: /home/b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:506: note: using lld-link: /home/b/sanitizer-x86_64-linux-fast/build/llvm_build_asan_ubsan/bin/lld-link
llvm-lit: /home/b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:506: note: using ld64.lld: /home/b/sanitizer-x86_64-linux-fast/build/llvm_build_asan_ubsan/bin/ld64.lld
llvm-lit: /home/b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:506: note: using wasm-ld: /home/b/sanitizer-x86_64-linux-fast/build/llvm_build_asan_ubsan/bin/wasm-ld
llvm-lit: /home/b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/utils/lit/lit/main.py:72: note: The test suite configuration requested an individual test timeout of 0 seconds but a timeout of 900 seconds was requested on the command line. Forcing timeout to be 900 seconds.
-- Testing: 86365 of 86366 tests, 88 workers --
Testing:  0.. 10.. 20.. 30.. 
TIMEOUT: Clangd Unit Tests :: ./ClangdTests/25/158 (2325 of 86365)
******************** TEST 'Clangd Unit Tests :: ./ClangdTests/25/158' FAILED ********************
Script(shard):
--
GTEST_OUTPUT=json:/home/b/sanitizer-x86_64-linux-fast/build/llvm_build_asan_ubsan/tools/clang/tools/extra/clangd/unittests/./ClangdTests-Clangd Unit Tests-3239540-25-158.json GTEST_SHUFFLE=0 GTEST_TOTAL_SHARDS=158 GTEST_SHARD_INDEX=25 /home/b/sanitizer-x86_64-linux-fast/build/llvm_build_asan_ubsan/tools/clang/tools/extra/clangd/unittests/./ClangdTests
--

Note: This is test shard 26 of 158.
[==========] Running 8 tests from 8 test suites.
[----------] Global test environment set-up.
[----------] 1 test from BackgroundQueueTest
[ RUN      ] BackgroundQueueTest.Boost
[       OK ] BackgroundQueueTest.Boost (0 ms)
[----------] 1 test from BackgroundQueueTest (0 ms total)

[----------] 1 test from CompletionTest
[ RUN      ] CompletionTest.NamespaceDoubleInsertion
Built preamble of size 214340 for file /clangd-test/foo.cpp version null in 11.46 seconds
Ignored diagnostic. /clangd-test/foo.cpp:5:5:expected unqualified-id
Sema said no scope specifier, but we saw ns:: in the source code
Code complete: fuzzyFind({
  "AnyScope": false,
  "Limit": null,
  "PreferredTypes": [],
  "ProximityPaths": [
    "/clangd-test/foo.cpp"
  ],
  "Query": "ABC",
  "RestrictForCodeCompletion": true,
  "Scopes": [
    "foo::ns::",
    "ns::"
  ]
})
Code complete: sema context TopLevel, query scopes [foo::ns::,ns::] (AnyScope=false), expected type <none>
Code complete: 0 results from Sema, 1 from Index, 0 matched, 0 from identifiers, 1 returned.
[       OK ] CompletionTest.NamespaceDoubleInsertion (37228 ms)
[----------] 1 test from CompletionTest (37228 ms total)

[----------] 1 test from DexTest
Step 10 (stage2/asan_ubsan check) failure: stage2/asan_ubsan check (failure)
...
llvm-lit: /home/b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:506: note: using ld64.lld: /home/b/sanitizer-x86_64-linux-fast/build/llvm_build_asan_ubsan/bin/ld64.lld
llvm-lit: /home/b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:506: note: using wasm-ld: /home/b/sanitizer-x86_64-linux-fast/build/llvm_build_asan_ubsan/bin/wasm-ld
llvm-lit: /home/b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:506: note: using ld.lld: /home/b/sanitizer-x86_64-linux-fast/build/llvm_build_asan_ubsan/bin/ld.lld
llvm-lit: /home/b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:506: note: using lld-link: /home/b/sanitizer-x86_64-linux-fast/build/llvm_build_asan_ubsan/bin/lld-link
llvm-lit: /home/b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:506: note: using ld64.lld: /home/b/sanitizer-x86_64-linux-fast/build/llvm_build_asan_ubsan/bin/ld64.lld
llvm-lit: /home/b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:506: note: using wasm-ld: /home/b/sanitizer-x86_64-linux-fast/build/llvm_build_asan_ubsan/bin/wasm-ld
llvm-lit: /home/b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/utils/lit/lit/main.py:72: note: The test suite configuration requested an individual test timeout of 0 seconds but a timeout of 900 seconds was requested on the command line. Forcing timeout to be 900 seconds.
-- Testing: 86365 of 86366 tests, 88 workers --
Testing:  0.. 10.. 20.. 30.. 
TIMEOUT: Clangd Unit Tests :: ./ClangdTests/25/158 (2325 of 86365)
******************** TEST 'Clangd Unit Tests :: ./ClangdTests/25/158' FAILED ********************
Script(shard):
--
GTEST_OUTPUT=json:/home/b/sanitizer-x86_64-linux-fast/build/llvm_build_asan_ubsan/tools/clang/tools/extra/clangd/unittests/./ClangdTests-Clangd Unit Tests-3239540-25-158.json GTEST_SHUFFLE=0 GTEST_TOTAL_SHARDS=158 GTEST_SHARD_INDEX=25 /home/b/sanitizer-x86_64-linux-fast/build/llvm_build_asan_ubsan/tools/clang/tools/extra/clangd/unittests/./ClangdTests
--

Note: This is test shard 26 of 158.
[==========] Running 8 tests from 8 test suites.
[----------] Global test environment set-up.
[----------] 1 test from BackgroundQueueTest
[ RUN      ] BackgroundQueueTest.Boost
[       OK ] BackgroundQueueTest.Boost (0 ms)
[----------] 1 test from BackgroundQueueTest (0 ms total)

[----------] 1 test from CompletionTest
[ RUN      ] CompletionTest.NamespaceDoubleInsertion
Built preamble of size 214340 for file /clangd-test/foo.cpp version null in 11.46 seconds
Ignored diagnostic. /clangd-test/foo.cpp:5:5:expected unqualified-id
Sema said no scope specifier, but we saw ns:: in the source code
Code complete: fuzzyFind({
  "AnyScope": false,
  "Limit": null,
  "PreferredTypes": [],
  "ProximityPaths": [
    "/clangd-test/foo.cpp"
  ],
  "Query": "ABC",
  "RestrictForCodeCompletion": true,
  "Scopes": [
    "foo::ns::",
    "ns::"
  ]
})
Code complete: sema context TopLevel, query scopes [foo::ns::,ns::] (AnyScope=false), expected type <none>
Code complete: 0 results from Sema, 1 from Index, 0 matched, 0 from identifiers, 1 returned.
[       OK ] CompletionTest.NamespaceDoubleInsertion (37228 ms)
[----------] 1 test from CompletionTest (37228 ms total)

[----------] 1 test from DexTest

```

</details>

https://github.com/llvm/llvm-project/pull/110155