webp: error: can't find a register in class 'BREG' while reloading 'asm'

[erg@…]

I received an error message when trying to build libwebp on Leopard. The problem occurs in webp/work/libwebp-0.1.3/src/dsp/cpu.c. The error message is

 In function 'GetCPUInfo':
cpu.c:35: error: can't find a register in class 'BREG' while reloading 'asm'
#

[mf2k (Frank Schima)]

Please attach the main.log.

[ryandesign (Ryan Carsten Schmidt)]

Thanks for the report, Emden. I had only tried to use it on Snow Leopard so far. There is a ​pre-compiled binary for Leopard on the webp project's downloads page, so it must be possible to compile it... I'll try to look into this problem soon.

[ryandesign (Ryan Carsten Schmidt)]

I see ​this similar report, indicating it's a problem with position-independent code, which on OS X is generated by default; it shows flags we could try to disable PIC. Alternately, it suggests it's a problem with the old gcc on Leopard; we could try using gcc 4.2 which is also available in Leopard's Xcode, but not on Tiger's, so we'd need a different solution there. Finally, we should report this to the developers of webp. I checked the binary they have for Leopard, and it's compiled only for x86_64, which is strange because that's not the default architecture on Leopard. Perhaps it was made on Snow Leopard, with Snow Leopard's newer gcc. I will test these various theories when I get back to my Leopard machine.

[ryandesign (Ryan Carsten Schmidt)]

I verified that using gcc-4.2 on Leopard works, so that's what I did in r88797. I still intend to find a different solution for Tiger later.

[ryandesign (Ryan Carsten Schmidt)]

I can't get it to build on Tiger. I have reported the problem to the developers of webp as ​issue 103.