[PATCH v4] Add support for SoftFloat library on ARM (original) (raw)

Jakub Vaněk linuxtardis at gmail.com
Wed Dec 12 14:36:07 UTC 2018

Hi Erik,

On 2018-12-12 at 15:41 +0300, Boris Ulasevich wrote:

Hi Jakub,

I do not understand why you use memcpy in softfloatarm.cpp. If type cast is the only reason why don't you use reinterpretcast? regards, Boris

I'm using memcpy there because float32_t is a struct containing a single uint32_t member. I think that the proper way of doing a byte- level conversion between different types (type punning) is via memcpy. If I used a casted pointer, this would violate the rule that I can access a memory location through a pointer of only one type. Using union for this seems to be also undefined in C++, as then I would access the value through a non-active member.

Thanks,

Jakub

On 10.12.2018 23:23, Jakub Vaněk wrote: > Hi Erik, > > On 2018-12-10 at 09:39 -0800, Erik Joelsson wrote: > > The build changes look ok to me. > > > > I do think --enable-softfloat is redundant as using any of the > > other > > parameters would imply it to be set, but it's ok to have it > > there. > > Thanks for the review. The motivation for this was that I was > closely > following how libffi is handled. The enable option was a workaround > for > the detection of softfloat in system paths. I don't think this is > how > the library is going to be used, so I removed this option. > > New patch can be found here: > https://github.com/ev3dev-lang-java/openjdk-ev3/blob/78a9d35986ed51273d9a3bb9878cbfcbe2488bfb/upstream/softfloat.patch > > Regards, > > Jakub > > > > > /Erik > > < raw patch at_ _> https://raw.githubusercontent.com/ev3dev-lang-java/openjdk-ev3/78a9d35986ed51273d9a3bb9878cbfcbe2488bfb/upstream/softfloat.patch > > >

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