[PATCH] Cygwin: fegetenv() in winsup/cygwin/fenv.cc should not disable exceptions!
Fri Aug 3 09:39:00 GMT 2018
On 2018-08-03 11:27, Houder wrote:
> I discovered a difference in behaviour between the x87 FPU and SSE.
> When an exception is masked, a "default action" is carried out when
> an exception occurs. At the same time the associated status flag is
> (the manual speaks about a "reasonable" default action, an action
> that is "sufficient" most of the times)
> When the exception is enabled again, SSE is not bothered. However
> the next _FPU_ statement will notice the status flag set, and will
> set the "Exception Summary Bit" (in the FPU's status register).
SSE has a "control and status register". The x87 FPU has a control
register and a status register.
Flags are only set in x87 FPU's status register when FPU statements
(the FPU is not "interested" in SSE's control and status register)
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