Outstanding. Thanks. I thought that putting the code in a sub would hit the performance of the vec4 version.

From what (little) I understand of what just scanned, I have to agree with your statement that (at this level at least) Inline C == XS.

When I (eventually) succeed in building my own copy of perl, it will definately be "Inline C for me", for this sort of thing.

Now if only I could find someone who could explain what this means....

Info: resolving __sys_nerr by linking to __imp___sys_nerr (auto-import
+)
fu000001.o(.idata$3+0xc): undefined reference to `libmsvcrt_a_iname'
nmth000000.o(.idata$4+0x0): undefined reference to `_nm___sys_nerr'
dmake.exe:  Error code 1, while making '..\miniperl.exe'
[download]

Or rather, I know what an Unresolved Symbol is, but how to track down the source. I grepped and grepped for those weird filenames and can't find hide nor haor of them:(