To disable (or not) assembler modules?

Ryan Schmidt ryandesign at
Mon Mar 15 00:54:46 PDT 2010

On Mar 14, 2010, at 08:52, Tabitha McNerney wrote:

> I noticed that some ports use the configure option:
> --disable-asm
> I looked up what this means and found in some ReadMe files of the source distribution of, for example, libgcrypt:
> Do not use assembler modules.  It is not possible to use this on some CPU types.
> Are there any general rules as to why assembler modules should in fact be disabled on, say, PowerPC or Intel based Apple machines? 

I believe these were added to some ports during the Intel transition, because the ports would not compile without it. Perhaps the assembly used was meant for other Intel processors, and not the Core family used in Macs. Or perhaps somehow the PowerPC assembly ended up being used instead of the Intel version. It would be on a case-by-case basis, so for each such port you've discovered, you could use "svn blame" to find the revision in which that line was added, then look at the commit message to find out why. Perhaps some of those ports no longer require that option, if later versions of the software have fixed their use of assembly to be Mac-Intel-compatible. In general, I would assume it would be preferable to enable assembly, since it is probably faster.

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