Messages in this thread | | | From | (H. Peter Anvin) | Subject | Re: Intel floating-point initialization | Date | 19 May 1998 10:36:11 GMT |
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Followup to: <19980519101452.11458@pauillac.inria.fr> By author: Xavier Leroy <Xavier.Leroy@inria.fr> In newsgroup: linux.dev.kernel > > I beg to disagree with Linus. The parent process/thread may have set > the FPU control word to a non-default value (i.e. change rounding > modes, etc). The programmer legitimely expects the child process to > inherit those settings (just like it inherits pretty much everything > else from its parent). >
If the FPU registers are otherwise preserved across a system call, they should be copied by fork(). Otherwise it will not work properly if you use floating point in the same routine that does a fork() (remember, to the C compiler, fork() is just another function.)
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