[U-Boot-Users] FW: [PATCH][ARM] Rationalize ARM compiler options

[Ulf Samuelsson]

>> > 
>> > Please don't add too many empty lines.
>> >
>> 
>> OK - I'll change thie when I re-submit. 
>> I just like to be able to ripple thru my buffers to animate 
>> the differences between almost identical files.
>>  
>> > Why exactly are you dropping -msoft-float here?
>> 
>> I was under the delusion that dropping this protected against 
>> incorporation of floating point instructions. 
>> 
>> Have I now got a clear understanding of the position:-
>> 
>> "
>> The use of floating point arithmetic in the U-Boot code is 
>> deprecated. 
>> However the ELDK toolchains provide floating point support 
>> and were built with the -msoft-float option. This option is 
>> supplied to the code to ensure any floating point arithmetic 
>> included links in the floating point support code correctly. 
>> " 
>> 
>> If so I'll put -msoft-float in all arm config.mk files.

Please DON'T!
This *forces* you to compile U-Boot with a compiler suite which is
configured to generate soft-float.
If you happen to use a compiler which does not support soft-float,
I.E: uses NWFPE, then the build will fail.

Also what happens if you have a toolchain built without V5 support?
Will the build complete?

>> 
>> > 
>> > > -# Make ARMv5 to allow more compilers to work, even though its v6.
>> > > -PLATFORM_CPPFLAGS += -march=armv5
>> > > +PLATFORM_CPPFLAGS += -march=armv6
>> > 
>> > Why exactly are you changing this?
>> 
>> arm1136 is an ARM Architecture V6 processor.
>> 
>> My position is:
>> "
>> The main (arm) tree processor options should use the correct 
>> architecture option for the processor (provided this option 
>> is accepted without error or warning  by the ELDK arm 
>> toolchains) Users using compilers which do not support the 
>> correct architecture should be made aware of this.
>> Should they wish to use another compiler they can change this 
>> option locally.
>> "

Why not make this user tunable.
If you want to mess about with V4 vs V5 support you should,
but don't enforce this for people that could care less.

>> I would also accept
>> (reluctantly, although it saves lots of space I could waste 
>> as empty lines ;-) )
>> 
>> "
>> For simplicity, the main (arm) tree processor options use the 
>> lowest common architecture option (armv4), whatever the 
>> processor implements. Users can change this option locally.  
>> "
>> 
>> At present we have a mixture.....
>> 
>> Regards
>> 
>> Peter
>> 


Best Regards
Ulf Samuelsson