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Xun, All, On Sunday 27 March 2011 19:54:09 Xun Li wrote: > I would need to use -msoft-float options to simulate floating point > calculations, hence I would need multilib to be enabled in the cross > compiler. You do not need multilib to enable soft-float. You can have the toolchain be entirely soft-float by default. Multilib is needed if you want the _same_ toolchain to be able to emit both HW and SW floating point operations. (Note: the compiler itself is able to generate both SW and HW, but the libraries have to be compiled twice, once for each case). > How to do this in the crosstool? Do you mean crostool, as 'the original crosstool by Dan KEGEL' and hosted there: http://kegel.com/crosstool/ ? Or do you mean crosstool-NG, as 'the fork by Yann E. MORIN" and hosted there: http://ymorin.is-a-geek.org/projects/crosstool ? If the former, I don't really know. I think crosstool had support for building multilb, but I never tried. For the latter, no, crostool-NG does not support multilib. Properly doing so is not easy. Multilib has a broad meaning, depending on the architecture you speak about. For example: - x86: - 32-bit and 64bit, - SW and HW floats --> 4 combinations - ARM: - SW and HW floats - float format: VFP vs. softfp vs. NEON vs. Maverick (not too sure I'm not speaking with my ass here...) - armv4, armv5, armv6, armv7 - big and little endian - ARM vs. Thumb - with or without interworking - ARM vs. ARM26 (although ARM26 is really dead nowadays) - OABI vs. EABI --> a hell of a lot of combinations! (1024 if I count correctly?) MIPS: - Pfff. I don't even want to try listing it... --> a lot of conbinations as well (but less than for ARM?) And for each combination in said architecture, we'd need to build all of the libraries running on the target. And even if you can do it, we'd need a way to configure the subset of multilib we'd want. For now, I'd recommend to build one toolchain for each combination you need. Basically, that boils down to two toolchain if you are only interested in HW vs. SW floating point. Regards, Yann E. MORIN. -- .-----------------.--------------------.------------------.--------------------. | Yann E. MORIN | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: | | +33 662 376 056 | Software Designer | \ / CAMPAIGN | ___ | | +33 223 225 172 `------------.-------: X AGAINST | \e/ There is no | | http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL | v conspiracy. | '------------------------------^-------^------------------^--------------------' -- For unsubscribe information see http://sourceware.org/lists.html#faq
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