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[71.190.212.171]) by smtp.gmail.com with ESMTPSA id m19sm2937512qtp.93.2021.06.10.14.36.13 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Thu, 10 Jun 2021 14:36:14 -0700 (PDT) In-Reply-To: <83y2bhbw14.fsf@gnu.org> (Eli Zaretskii's message of "Thu, 10 Jun 2021 18:04:55 +0300") X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.io gmane.emacs.bugs:208338 Archived-At: EZ> Is it, really? Yes. While I can't claim to be any more knowledgeable, the naivete of someone protesting thread atomicity based on word-size is stunningly apparent. EZ> And you can show a GDB backtrace with values of the variable that supports EZ> that? Alas I cannot. My gdb skills are less impressive in the presence of threads, and heisenbugs of this nature tend to mysteriously disappear when gdb's leisurely pace gives caches ample time to flush. I mentioned earlier I could not reproduce my MRE failure when I merely inserted print statements. My patch isn't quite as studied as Pip Cet's (my patch merely skirts locking the glib unless you're main-thread-p), but it does fix OP and, unlike the current state of the code, doesn't admit glaring theoretical flaws, even though you seem to think those flaws could never materialize in practice despite evidence (gdb-less as it is) to the contrary.