Re: 9.4 broken on alpha

Tom Lane wrote:
> Alvaro Herrera <alvherre(at)2ndquadrant(dot)com> writes:
> > Aaron W. Swenson wrote:
> >> In the 4 years that that particular line has been there, not once had
> >> anyone else run into it on Gentoo until a couple months ago.
> >> And it isn't a case of end users missing it as we have arch testers
> >> that test packages before marking them suitable for public consumption.
> >> Alpha is one of the arches.
>
> > This means that not once has anybody compiled in an Alpha in 4 years.
>
> Well, strictly speaking, there were no uses of pg_read_barrier until 9.4.
> However, pg_write_barrier (which used "wmb") was in use since 9.2; so
> unless you're claiming your assembler knows wmb but not rmb, the code's
> failed to compile for Alpha since 9.2.

Actually according to this
http://www.cs.cmu.edu/afs/cs.cmu.edu/academic/class/15213-f98/doc/alpha-asm.pdf
there is a wmb instruction but there is no rmb.

--
Álvaro Herrera http://www.2ndQuadrant.com/
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