[arm-gnu] Regarding Double Data Type Support on Cortex M4

[Carlos O'Donell]

On 6/1/2012 10:27 AM, Vikas R wrote:
> I have used following command to compile my main.c file. The option -mfloat-abi=softfp helps me to support float datatype on  MK60FN1M0VLQ12 (COTREX-M4) when I kept FPU enabled.
> arm-none-eabi-gcc -Wall -mfloat-abi=softfp -mcpu=cortex-m4 -mthumb -Qn -Os  -mlong-calls -c main.c -o main.o
> 
> If you know any  GCC compiler commands to solve the above problem, please let me know.

Sourcery CodeBench Lite for ARM EABI does support compiling application code for the Cortex-M4F.

The FPU on the Cortex-M4F is not a full VFP so you need to pass:

`-mfpu=fpv4-sp-d16 -mfloat-abi=softfp`

Without specifying -mfpu you likely generate floating point instructions that are unsupported by the M4F's single-precision floating point unit.

Does that help?

Cheers,
Carlos.
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Carlos O'Donell
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