Rollup merge of #22903 - semarie:openbsd-stack, r=alexcrichton
Rollup merge of #22903 - semarie:openbsd-stack, r=alexcrichton

 some commits in OpenBSD OS have corrected a problem of stack position.
Now, we can adjust more accurately the page guard in rust.

@dhuseby I am not sure that bitrig have already integrated these changes (the `$OpenBSD$` header in sys/kern/kern_exec.c is too old). But when they do, you may want this patch too.

aneeshusa/rust,AerialX/rust,vhbit/rust,mdinger/rust,krzysz00/rust,carols10cents/rust,pshc/rust,aneeshusa/rust,victorvde/rust,ebfull/rust,andars/rust,cllns/rust,sae-bom/rust,AerialX/rust-rt-minimal,gifnksm/rust,aepsil0n/rust,zaeleus/rust,cllns/rust,dwillmer/rust,rohitjoshi/rust,miniupnp/rust,zubron/rust,vhbit/rust,vhbit/rust,l0kod/rust,graydon/rust,krzysz00/rust,rprichard/rust,jashank/rust,TheNeikos/rust,miniupnp/rust,mahkoh/rust,miniupnp/rust,philyoon/rust,mihneadb/rust,victorvde/rust,mihneadb/rust,graydon/rust,seanrivera/rust,miniupnp/rust,nwin/rust,ejjeong/rust,zubron/rust,zachwick/rust,aneeshusa/rust,robertg/rust,kwantam/rust,TheNeikos/rust,TheNeikos/rust,KokaKiwi/rust,TheNeikos/rust,zubron/rust,nwin/rust,zaeleus/rust,rprichard/rust,ejjeong/rust,rprichard/rust,zubron/rust,reem/rust,omasanori/rust,dwillmer/rust,ebfull/rust,AerialX/rust-rt-minimal,krzysz00/rust,jroesch/rust,mvdnes/rust,mahkoh/rust,nwin/rust,jroesch/rust,vhbit/rust,seanrivera/rust,GBGamer/rust,l0kod/rust,rohitjoshi/rust,seanrivera/rust,GBGamer/rust,mahkoh/rust,AerialX/rust-rt-minimal,pelmers/rust,aidancully/rust,robertg/rust,reem/rust,aneeshusa/rust,TheNeikos/rust,seanrivera/rust,andars/rust,GBGamer/rust,dwillmer/rust,ejjeong/rust,sae-bom/rust,zubron/rust,dwillmer/rust,gifnksm/rust,zaeleus/rust,rprichard/rust,victorvde/rust,robertg/rust,jashank/rust,rohitjoshi/rust,zachwick/rust,andars/rust,jroesch/rust,ebfull/rust,ejjeong/rust,l0kod/rust,dwillmer/rust,andars/rust,aepsil0n/rust,KokaKiwi/rust,cllns/rust,ejjeong/rust,miniupnp/rust,mahkoh/rust,sae-bom/rust,AerialX/rust-rt-minimal,zubron/rust,reem/rust,robertg/rust,ruud-v-a/rust,vhbit/rust,kwantam/rust,avdi/rust,mihneadb/rust,mdinger/rust,cllns/rust,pelmers/rust,krzysz00/rust,robertg/rust,krzysz00/rust,sae-bom/rust,sae-bom/rust,jashank/rust,carols10cents/rust,rohitjoshi/rust,GBGamer/rust,XMPPwocky/rust,pshc/rust,KokaKiwi/rust,avdi/rust,philyoon/rust,victorvde/rust,robertg/rust,zachwick/rust,graydon/rust,zaeleus/rust,sae-bom/rust,carols10cents/rust,omasanori/rust,zaeleus/rust,zubron/rust,avdi/rust,pelmers/rust,reem/rust,gifnksm/rust,GBGamer/rust,dwillmer/rust,pshc/rust,avdi/rust,rprichard/rust,mahkoh/rust,vhbit/rust,aidancully/rust,mihneadb/rust,mihneadb/rust,l0kod/rust,gifnksm/rust,zachwick/rust,omasanori/rust,aepsil0n/rust,AerialX/rust,jroesch/rust,zachwick/rust,seanrivera/rust,victorvde/rust,kwantam/rust,XMPPwocky/rust,mihneadb/rust,graydon/rust,TheNeikos/rust,nwin/rust,reem/rust,omasanori/rust,andars/rust,mvdnes/rust,XMPPwocky/rust,jashank/rust,carols10cents/rust,jashank/rust,mahkoh/rust,rohitjoshi/rust,krzysz00/rust,ruud-v-a/rust,nwin/rust,aepsil0n/rust,ejjeong/rust,aidancully/rust,GBGamer/rust,philyoon/rust,miniupnp/rust,pelmers/rust,nwin/rust,ebfull/rust,philyoon/rust,mvdnes/rust,pelmers/rust,avdi/rust,XMPPwocky/rust,graydon/rust,gifnksm/rust,vhbit/rust,mdinger/rust,pshc/rust,aneeshusa/rust,ebfull/rust,KokaKiwi/rust,aneeshusa/rust,KokaKiwi/rust,GBGamer/rust,ruud-v-a/rust,pelmers/rust,AerialX/rust,ebfull/rust,aidancully/rust,jashank/rust,jashank/rust,rohitjoshi/rust,philyoon/rust,mvdnes/rust,l0kod/rust,graydon/rust,aepsil0n/rust,jroesch/rust,rprichard/rust,l0kod/rust,mdinger/rust,l0kod/rust,aidancully/rust,dwillmer/rust,nwin/rust,carols10cents/rust,miniupnp/rust,XMPPwocky/rust,philyoon/rust,kwantam/rust,omasanori/rust,mvdnes/rust,zachwick/rust,victorvde/rust,kwantam/rust,jroesch/rust,vhbit/rust,cllns/rust,jroesch/rust,carols10cents/rust,pshc/rust,aidancully/rust,pshc/rust,andars/rust,AerialX/rust,gifnksm/rust,mvdnes/rust,pshc/rust,mdinger/rust,jashank/rust,GBGamer/rust,ruud-v-a/rust,KokaKiwi/rust,nwin/rust,ruud-v-a/rust,dwillmer/rust,cllns/rust,AerialX/rust-rt-minimal,pshc/rust,avdi/rust,omasanori/rust,zaeleus/rust,miniupnp/rust,aepsil0n/rust,mdinger/rust,reem/rust,AerialX/rust-rt-minimal,AerialX/rust,seanrivera/rust,XMPPwocky/rust,zubron/rust,ruud-v-a/rust,kwantam/rust,AerialX/rust,l0kod/rust,jroesch/rust