(sin #.SB-EXT:SINGLE-FLOAT-POSITIVE-INFINITY) bombs SBCL

[Sean Luke]

SBCL 1.1.6.0-3c5581a
Darwin geepers-8771.local 17.7.0 Darwin Kernel Version 17.7.0: Mon Aug 31 22:11:23 PDT 2020; root:xnu-4570.71.82.6~1/RELEASE_X86_64 x86_64

In most programming languages, sin(infinity) returns NaN. One would expect this behavior on SBCL if traps are turned off, or at least to raise a condition if traps were turned on. But neither happens: instead, SBCL bombs hard.

It's easily replicated:

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This is SBCL 1.1.6.0-3c5581a, an implementation of ANSI Common Lisp.
More information about SBCL is available at <http://www.sbcl.org/>.

SBCL is free software, provided as is, with absolutely no warranty.
It is mostly in the public domain; some portions are provided under
BSD-style licenses. See the CREDITS and COPYING files in the
distribution for more information.
* (sin #.SB-EXT:SINGLE-FLOAT-POSITIVE-INFINITY)
fatal error encountered in SBCL pid 80419:
set_pseudo_atomic_atomic: pseudo atomic bits is 44038880.

Welcome to LDB, a low-level debugger for the Lisp runtime environment.
ldb>

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Alternatively you could do something like this:

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This is SBCL 1.1.6.0-3c5581a, an implementation of ANSI Common Lisp.
More information about SBCL is available at <http://www.sbcl.org/>.

SBCL is free software, provided as is, with absolutely no warranty.
It is mostly in the public domain; some portions are provided under
BSD-style licenses. See the CREDITS and COPYING files in the
distribution for more information.
* (sb-int:set-floating-point-modes :traps '(:invalid))

* (sin (exp 1000))
fatal error encountered in SBCL pid 80451:
set_pseudo_atomic_atomic: pseudo atomic bits is 18869216.

Welcome to LDB, a low-level debugger for the Lisp runtime environment.
ldb>

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[Douglas Katzman (dougk)]

SBCL 1.1.6 is 8 years old. You need to upgrade.