Re: solaris build problem with Sun compilers

[Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>]

Alan Stange <stange(at)rentec(dot)com> writes:
> - postgresql HEAD when using the Solaris compilers spro9 or newer will 
> only run on v9 based hardware using v8plus or v9 platform.
> - postgresql HEAD when using gcc will run on anything as they generate 
> code for the v7 platform by default and the cas instruction isn't used 
> in any assembler code in postgresql.

I gather from the contents of solaris_sparc.s that the Sun compilers can
be expected to define __sparcv9 if compiling for v9 hardware.  I'm
inclined to #ifdef things so that we use cas if that symbol's defined and
ldstub if not.  I'm not sure if gcc can be expected to define the same
symbol --- we might end up using ldstub always, even if we try to
conditionalize the code for gcc.

Or we could just revert to ldstub.  This seems like a lot of complexity
for a so-far-entirely-hypothetical performance gain ...

			regards, tom lane