[arm-gnu] Supporting __softfp compiler directive

[Alhad Purnapatre <alhadp@xxxxxxxxxxxx>]

Hello,

We are trying to ensure that headers released for the BREW platform 
compile on popular toolchains used by BREW application developers, 
including CodeSourcery and RVCT.
In order to have a consistent floating point ABI irrespective of 
available floating point hardware support or linking options used, we 
tried postfixing __softfp compiler directive to the floating point 
function pointers that define BREW interfaces. __softfp ensures that 
floating point arguments to functions are passed in integer registers, 
not VFP registers. The directive supported by RVCT, but doesn't seem to 
work on CodeSourcery.
Here is the RVCT 4.0 documentation that refers to this directive:
<http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0205i/CIHGHCAC.html>

I tried using the following using version arm-none-eabi-g++.exe 
(Sourcery G++ Lite 2009q3-68) 4.4.1:
alhadp@ALHADP /c/Program Files/CodeSourcery/Sourcery G++ Lite/bin
$ cat test.cpp
typedef struct {
double (*wstrtofloat) (const char *pszNum) __softfp;
}foovtbl;
<snip>

alhadp@ALHADP /c/Program Files/CodeSourcery/Sourcery G++ Lite/bin
$ ./arm-none-eabi-g++.exe -c test.cpp
test.cpp:2: error: expected ';' before '__softfp'
<snip>

The only way we can get the desired linkage is by using this:
#pragma push
#pragma softfp_linkage
<API declaration>
#pragma pop

But that cannot be used inside of macros, which is how most of our 
interfaces are defined.
I have a couple of questions

1) Is there a plan to support the VFP ABI?
2) Also, is there a plan for forcing softfp on architectures that 
default to VFP?
Please let us know if you need more information. Appreciate your time.

Thanks,
Alhad