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From: "stsp at users dot sourceforge.net" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug sanitizer/101476] AddressSanitizer check failed, points out a
 (potentially) non-existing stack error and pthread_cancel
Date: Tue, 25 Jan 2022 10:35:35 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D101476

--- Comment #13 from Stas Sergeev <stsp at users dot sourceforge.net> ---
Found another problem.
https://github.com/gcc-mirror/gcc/blob/master/libsanitizer/asan/asan_posix.=
cpp#L53
The comment above that line talks about
SS_AUTODISARM, but the line itself does
not account for any flags. In a mean time,
linux returns SS_DISABLE in combination
with flags, like SS_AUTODISARM. So the
"!=3D" check should not be used.

My app probes for SS_AUTODISARM by trying
to set it, and after that, asan breaks.
This is quite cludgy though.
Should the check be changed to
if (!(signal_stack.ss_flags & SS_DISABLE))
or maybe linux should not return any flags
together with SS_DISABLE?
man page talks "strange things" on that subject.=