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0 pointsMaulingMonkey9y ago0 comments

Yes - perhaps I should have written that as "volatile AND memory barriers". Either way, worth mentioning, as it's a common misunderstanding.

Further complicating matters is the fact that Microsoft's compilers will treat volatile as a memory barrier - for x86 code. But not for ARM! https://msdn.microsoft.com/en-us/library/jj204392.aspx

0 comments

jedmeyers9y ago

Same thing might be with jvm. On x86 'concrete machine' volatile might be a memory barrier, but this behavior is not guaranteed by the definitions of Java 'abstract machine'.

j / k navigate · click thread line to collapse

0 pointsMaulingMonkey9y ago0 comments

Yes - perhaps I should have written that as "volatile AND memory barriers". Either way, worth mentioning, as it's a common misunderstanding.

Further complicating matters is the fact that Microsoft's compilers will treat volatile as a memory barrier - for x86 code. But not for ARM! https://msdn.microsoft.com/en-us/library/jj204392.aspx

0 comments

jedmeyers9y ago

Same thing might be with jvm. On x86 'concrete machine' volatile might be a memory barrier, but this behavior is not guaranteed by the definitions of Java 'abstract machine'.

j / k navigate · click thread line to collapse