[Buildroot] ARM EABI builds

[Bernhard Fischer <rep.dot.nop@gmail.com>]

On Thu, Jun 28, 2007 at 03:54:22PM -0400, Stuart Wood wrote:
>Just a note on what Tom said about user land application. I've already 

Just as a note on what everybody seems to say about configuring GCC:
It is very amusing that you guys seem to be excited about _not_ setting
a config option -- CONFIG_BR2_EXTRA_TARGET_GCC_CONFIG_OPTIONS -- which
is specifically exported to you, to spell out specific requirements put
upon gcc (other toolchain parts of course also provide said means for
hand-crafted  options, mind you).

>found that I had to add -march=armv4t to properly build my application, Just

doh!

>because gcc was not using the right load register code for the data 

well, if you don't tell it to do and _do not help in improving the
generic situation_ how should we guess what you are trying to achieve?

Get real. (yes, i'm in a bad mood and i'm fond of stupid whining about
'Doctor, it hurts when i..'

Q:
Dear X-mas whatever. I want this and that. Now. Immediately. No, i have
no idea how to implement 'this' 'now', but it has to be done. What? Nah,
no idea what 'this' nor 'that' nor 'now' is supposed to do, i'd have
provided a guidance otherwise.
A: alright. At your service.

>size I wanted to read. It would use ldrw instead of ldrh. So, It would 
>help avoid those errors.

Try searching the archives for CPU selection (from memory, so may not be
accurate) for further details.
>
>Stuart

See below.
>
>Tom wrote:
>> 
>> I did think about adding -mcpu=<cpu> to the build CFLAGS, but that is
>> not going to help with the problem that libgcc is not going to be 
>> compiled correctly.
>> 
>Why not? The kernel image, built with the same "incorrect" toolchain, 
>must have used only ARMv4 instructions. If it hadn't, I would have never 
>gotten far enough to even execute vprintf, libc. I would suspect that 
>the kernel does a better job of setting -mcpu, -mtune. Thus these 
>options should work for libc too. What makes you think that it wouldn't 
>work for libc, have you tried? (PS: Even if it did, bug #1406 is 
>probably the better fix, in particular as buildroot users might use its 

bug #1406 is completely crap. Let me cite:
<quote>
 Reporter  	 bjdooks
 Summary  	 0001403: printf and anything using vfprintf() hangs
 system
 Description 	Any function using vfprintf, such as printf and snprintf
 cause the system to stop. A test program shows that stdout is
 functional, as fwrite() to stdout will display messages on the console
 Additional Information 	uclibc 0.9.29
 gcc 4.1.2 (arm-linux-uclibcgnueabi)
 binutils 2.17.50.0.16
 configure for ARM920T, EABI
---
(0002514)
bjdooks
06-25-07 17:26

	The bug is still present in the development snapshot 
---
(0002517)
bjdooks
06-26-07 05:03

	Building gcc 4.1.2 for OABI (patches will be sent in seperate
	report) does not work either.
</quote>
>toolchain to build their own code w/o always setting these options)

- No actual error shown.
- no code/arch/toolchain hints to reproduce.
This is one of the 'Doctor, it hurts'.. goto above;