[PSA]: Correctness issue in GHC-9.12
Andreas Klebinger via ghc-devs <[email protected]> Fri, 17 Jan 2025 12:02:55 +0100
| Newsgroups | gmane.comp.lang.haskell.ghc.devel,gmane.comp.lang.haskell.glasgow.user |
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A bug in 9.12.1 was reported and confirmed (ghc bug
https://gitlab.haskell.org/ghc/ghc/-/issues/25653) which can lead to
incorrect runtime results in compiled programs.
In particular this seems to happen for sub-word divisions with a known
divisor when optimizations are enabled and affects at least the x86
backend, although it=E2=80=99s likely that other backends are also affecte=
d.
We plan to release a bug fix release 9.12.2 in the near future to
address this issue and recommend people do not upgrade until then.
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<head>
<meta http-equiv=3D"content-type" content=3D"text/html; charset=3DUTF-=
8">
</head>
<body>
<p
style=3D"margin-top: 0px; color: rgb(34, 34, 34); font-family: Arial, sans=
-serif; font-size: 16px; font-style: normal; font-variant-ligatures: norma=
l; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; or=
phans: 2; text-align: start; text-indent: 0px; text-transform: none; widow=
s: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: norm=
al; background-color: rgb(255, 255, 255); text-decoration-thickness: initi=
al; text-decoration-style: initial; text-decoration-color: initial;">A
bug in 9.12.1 was reported and confirmed (ghc bug
<a class=3D"moz-txt-link-freetext" href=3D"https://gitlab.haskell.or=
g/ghc/ghc/-/issues/25653">https://gitlab.haskell.org/ghc/ghc/-/issues/2565=
3</a>) which can lead
to incorrect runtime results in compiled programs.</p>
<p
style=3D"color: rgb(34, 34, 34); font-family: Arial, sans-serif; font-size=
: 16px; font-style: normal; font-variant-ligatures: normal; font-variant-c=
aps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-al=
ign: start; text-indent: 0px; text-transform: none; widows: 2; word-spacin=
g: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-co=
lor: rgb(255, 255, 255); text-decoration-thickness: initial; text-decorati=
on-style: initial; text-decoration-color: initial;">In
particular this seems to happen for sub-word divisions with a
known divisor when optimizations are enabled and affects at least
the x86 backend, although it=E2=80=99s likely that other backends ar=
e also
affected.</p>
<p
style=3D"color: rgb(34, 34, 34); font-family: Arial, sans-serif; font-size=
: 16px; font-style: normal; font-variant-ligatures: normal; font-variant-c=
aps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-al=
ign: start; text-indent: 0px; text-transform: none; widows: 2; word-spacin=
g: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-co=
lor: rgb(255, 255, 255); text-decoration-thickness: initial; text-decorati=
on-style: initial; text-decoration-color: initial;">We
plan to release a bug fix release 9.12.2 in the near future to
address this issue and recommend people do not upgrade until then.</=
p>
</body>
</html>
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