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Date: Mon, 10 Mar 2025 09:22:42 +0100
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Subject: [PHP-DEV] OPcache should zero out cache slots?
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From: rob@bottled.codes ("Rob Landers")

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Hello internals,

I=E2=80=99ve been trying to chase down a very subtle bug in 8.4 that onl=
y happens when OPcache is enabled (I'm trying to create a reproducer to =
file an actual bug). From what I can tell, OPcache doesn=E2=80=99t zero =
out cache slots, so occasionally, a cache slot will contain garbage that=
 happens to pass asserts/checks that causes the program to behave incorr=
ectly. Without OPcache, cache slots are always NULL if not set.

It's quite rare to end up in that situation, though, but I was wondering=
 if anyone has any opinions on this?

=E2=80=94 Rob
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<!DOCTYPE html><html><head><title></title><style type=3D"text/css">p.Mso=
Normal,p.MsoNoSpacing{margin:0}=0Ap.MsoNormal,p.MsoNoSpacing{margin:0}</=
style></head><body><div>Hello internals,<br></div><div><br></div><div>I=E2=
=80=99ve been trying to chase down a very subtle bug in 8.4 that only ha=
ppens when OPcache is enabled (I'm trying to create a reproducer to file=
 an actual bug). From what I can tell, OPcache doesn=E2=80=99t zero out =
cache slots, so occasionally, a cache slot will contain garbage that hap=
pens to pass asserts/checks that causes the program to behave incorrectl=
y. Without OPcache, cache slots are always NULL if not set.<br></div><di=
v><br></div><div>It's quite rare to end up in that situation, though, bu=
t I was wondering if anyone has any opinions on this?</div><div><br></di=
v><div id=3D"sig121229152">=E2=80=94 Rob<br></div></body></html>
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