Sergei Trofimovich authored Dec 19, 2018 and Ben Gamari committed Dec 26, 2018

Summary:
Initially -fno-stack-protector was added for openbsd specifically for ghc-6.5:
    changeset:f638fdfe (2006)
and later it was extended to cover osx:
    changeset:c2cd83e7

 (2009)

None of the reports hint at exact breakage. I guess both happened
in -fvia-C mode where GHC's Evil Mangler had a chance to mangle
stack canaries generated by fstack-protector.

ghc has no evil mangler anymore and the change is not needed
at least for C codegen.

validated the patch on OpenBSD-6.4. No new failures compared to
clean master branch.

Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>

Test Plan: validated on OpenBSD

Reviewers: bgamari

Subscribers: rwbarton, erikd, carter

GHC Trac Issues: #16046

Differential Revision: https://phabricator.haskell.org/D5465