Predator and CL did not provide any possible suspects.
Using Code Search for the file, "parser.cc" assigning to the concern owner.
Suspecting Commit#
https://chromium.googlesource.com/chromium/src/+/0fcc08c5d93f2e8128d5e583c236dd2a81e70a7b

@scottmg -- Could you please look into the issue, kindly re-assign if this is not related to your changes.
Thank You.

I'm not sure that's worth fixing. The repro is:

o=!!!...many...!!!E

Automatically applying components based on information from OWNERS files. If this seems incorrect, please apply the Test-Predator-Wrong-Components label.

For more information, please see https://chromium.googlesource.com/chromium/src/+/master/testing/libfuzzer/reference.md.

The link referenced in the description is no longer valid.

(bulk edit)

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/697f302d91e7ad4466416ab22c290c7fea9c6b93

commit 697f302d91e7ad4466416ab22c290c7fea9c6b93
Author: Penny MacNeil <pennymac@chromium.org>
Date: Mon Oct 30 21:29:41 2017

[GN fuzzer] Stack overflow fix.

Fuzzathon 2017.

Bug:  648076 , 749793 , 773426 , 768111 , 754972 , 734401 , 734200 
Change-Id: Ic608c5a374252809443a879ad4e2ddf8f6184697
Reviewed-on: https://chromium-review.googlesource.com/736159
Commit-Queue: Penny MacNeil <pennymac@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Reviewed-by: Max Moroz <mmoroz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#512626}
[modify] https://crrev.com/697f302d91e7ad4466416ab22c290c7fea9c6b93/tools/gn/parser_fuzzer.cc

ClusterFuzz has detected this issue as fixed in range 512623:512661.

Detailed report: https://clusterfuzz.com/testcase?key=4866002243551232

Fuzzer: libFuzzer_gn_parser_fuzzer
Job Type: libfuzzer_chrome_asan_debug
Platform Id: linux

Crash Type: Stack-overflow
Crash Address: 0x7ffe4237ee58
Crash State:
  Parser::ParseExpression
  Parser::Not
  
Sanitizer: address (ASAN)

Regressed: https://clusterfuzz.com/revisions?job=libfuzzer_chrome_asan_debug&range=480307:480308
Fixed: https://clusterfuzz.com/revisions?job=libfuzzer_chrome_asan_debug&range=512623:512661

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=4866002243551232

See https://chromium.googlesource.com/chromium/src/+/master/testing/libfuzzer/reference.md for more information.

If you suspect that the result above is incorrect, try re-doing that job on the test case report page.

ClusterFuzz testcase 4866002243551232 is verified as fixed, so closing issue as verified.

If this is incorrect, please add ClusterFuzz-Wrong label and re-open the issue.