lib/59853: compiler-rt softfloat lacks floating-point exceptions

[campbell+netbsd%mumble.net@localhost]

>Number:         59853
>Category:       lib
>Synopsis:       compiler-rt softfloat lacks floating-point exceptions
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    lib-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Dec 21 17:50:01 +0000 2025
>Originator:     Taylor R Campbell
>Release:        current, 11, 10, 9, ...
>Organization:
The NetBSD Exception, Inclangorated
>Environment:
>Description:
The softfloat code in compiler-rt never raises floating-point exceptions, neither as sticky bits by fetestexcept nor as traps with SIGFPE.

(The gcc softfloat code and the libc softfloat code, in contrast, do.)
>How-To-Repeat:
test fp exceptions in clang builds
>Fix:
Yes, please!